Peanut allergy: where do we stand, part 2

Dec. 5th, 2009

Since Feb. 2008, this second part of this article was started partly because of the enormous size of it (approx. 150 pages) and the difficulty manipulating it for updates and new postings. There's no table of contents yet, just scroll down to the various subjects or updates posted.

 

John Weisnagel, M.D.

See a recent special video

 
 

March 31st, 2010.

Even if you see the word "epidemic" relating to peanut allergy, mentioned occasionnaly, the latest being a book entitiled "The History of the Peanut Allergy Epidemic", according to published reliable articles in the medical literature, there is no such thing as an epidemic of peanut allergy. There is an increase in peanut allergy as other food allergies but as documented, it is a reflection of the increase in allergy generally over the years. There is no documented evidence that the so-called epidemic is caused by or related to immunizations (or vaccinations).

 

Recent status

-In Curr Opin Pediatr. 2010 Jul 30, Pansare M, Kamat D have an article summarizing the present state of Peanut Allergy.
Here's the abstract:

RECENT FINDINGS: Peanut allergy presents during early childhood. The prevalence of peanut allergy in children in developed countries appears to be increasing. Several factors, such as peanut-specific or environmental, are hypothesized as contributing to increased prevalence. However, there is no consensus on this matter. Component-related diagnostic tests are being explored to characterize clinical sensitivity. Currently, the primary treatment includes avoidance of peanut and immediate treatment of anaphylaxis. Recent peanut oral immunotherapy (OIT) trials achieved successful desensitization to peanuts in study participants, which may benefit many patients. Newer prospective studies are exploring effects of early high-dose peanut protein introduction versus avoidance in high-risk infants and development of peanut tolerance [Learning Early About Peanut Allergy (LEAP) study]. Several other immunotherapeutic approaches are being investigated in animal models. SUMMARY: There is no cure for peanut allergy. Peanut oral immunotherapy offers a potential treatment for desensitization. (posted Aug. 10th, 2010)

 

"Epidemiology of food allergy".Venter C, Arshad SH. Pediatr Clin North Am. 2011 Apr;58(2):327-49.


-Food allergy (FA) is perceived as a common problem, especially during childhood. Accurate assessment of incidence and prevalence of FA has been difficult to establish, however, due to lack of universally accepted diagnostic criteria. Although many foods are reported to cause IgE-mediated FA, most studies focus on 4 common food groups: cow's milk, hen's egg, peanut/tree nuts, and fish/shellfish. There may be variation in the prevalence of FA in regions of the world and a likely increase in prevalence has been observed in recent decades. This cannot be stated with confidence, however, without the use of consistent methodology and diagnostic criteria.

"Peanut allergy" Hourihane JO. Pediatr Clin North Am. 2011 Apr;58(2):445-58


-Peanut allergy may affect up to 2% of children in some countries, making it one of the most common conditions of childhood. Peanut allergy is a marker of a broad and possibly severe atopic phenotype. Nearly all children with peanut allergy have other allergic conditions. Peanut accounts for a disproportionate number of fatal and near fatal food-related allergies. Families with a child or children with peanut allergy can struggle to adapt to the stringent avoidance measures required. Although oral induction of tolerance represents the cutting edge of peanut allergy management, it is not yet ready for routine practice.

"Food allergy"  Susan Waserman and Wade Watson; excellent open access article published in Allergy Asthma Clin Immunol.    2011; 7(Suppl 1): S7.Copyright ©2011 Waserman and Watson; licensee BioMed Central Ltd. (posted Dec. 29th, 2011)


-In Clin Exp Allergy. 2010 Sep;40(9):1303-11. Byrne AM, Malka-Rais J, Burks AW, Fleischer DM published How do we know when peanut and tree nut allergy have resolved, and how do we keep it resolved?
It is worthwhile to read their abstract:


Over the last two decades, the prevalence of peanut and tree nut allergy has increased throughout the western world. Adverse reactions to these foods account for over 50% of all deaths resulting from food-related anaphylaxis. Until recently, evidence suggested that all peanut and tree nut allergy were permanent. It is now known that about 20% and 10%, respectively, of young patients outgrow peanut and tree nut allergies. Achieving tolerance is associated with increasing circulating T regulatory cells and reduced production of allergen-specific IgE. Reliable predictors of resolution are not yet available. A direct correlation between skin test weal size and allergen-specific IgE, at the time of diagnosis and likelihood of resolution, has been reported. Resolution of peanut or tree nut allergy cannot be determined conclusively by either allergen-specific IgE analysis or by skin prick testing. Oral food challenge is the gold standard for determining resolution of food allergy. Food challenges should only be undertaken in a clinical setting fully equipped to deal with a potential severe adverse reaction. Approximately 8% of patients who outgrow peanut allergy may suffer a recurrence, but recurrent tree nut allergy has not been reported to date. Infrequent ingestion of peanut may be related to the re-emergence of allergy. Induction of tolerance through oral immunotherapy or sublingual immunotherapy is now being actively studied, but remains experimental. Studies have reported short-term desensitization to peanut, but ongoing follow-up will determine whether tolerance is achieved long term. (posted

Jan 14th, 2012)

 

More on Anaphylaxis

-In Allergy. 2008 Aug;63(8):1071-6, de Silva et al, have an article entitled Paediatric anaphylaxis: a 5 year retrospective review. This was a retrospective case note study of children presenting with anaphylaxis over a 5-year period to the Emergency Department (ED) at the Royal Children's Hospital, Melbourne.

RESULTS: One-hundred and twenty-three cases of anaphylaxis in 117 patients were included. There was one death. The median age of presentation was 2.4 years. Home was the most common setting (48%) and food (85%) the most common trigger. Peanut (18%) and cashew nut (13%) were the most common cause of anaphylaxis. The median time from exposure to anaphylaxis for all identifiable agents was 10 min. The median time from onset to therapy was 40 min. Respiratory features were the principal presenting symptoms (97%). Seventeen per cent of subjects had experienced anaphylaxis previously.

CONCLUSIONS: This is the largest study of childhood anaphylaxis reported. Major findings are that most children presenting to the ED with anaphylaxis are first-time anaphylactic reactions and the time to administration of therapy is often significantly delayed. Most reactions occurred in the home. Peanut and cashew nut were the most common causes of anaphylaxis in this study population, suggesting that triggers for anaphylaxis in children have not changed significantly over the last decade. (posted Aug. 12th, 2008)

- In the J Allergy Clin Immunol. 2009 Aug;124(2):323-7. Epub 2009 Jun 27, Greenhawt MJ, Singer AM, Baptist AP, have a publication entitled Food allergy and food allergy attitudes among college students. With the help of an on-line survey among college students, the authors came to the following conclusion: Potentially life-threatening anaphylactic reactions to foods are occurring on college campuses. Only 39.7% of students with food allergy avoided a self-identified food allergen, and more than three fourths did not maintain SIE. Such behaviors might place these students at increased risk for adverse events. (posted Nov. 14th, 2009)

 

More on epinephrine

One Epinephrine Dose May Not Suffice for Children With Multiple Food Allergies

NEW YORK (Reuters Health) Jul 09 - Nearly one in five food-induced anaphylactic reactions that occur in children with multiple food allergies will require two or more doses of epinephrine, new research suggests. As reported in an upcoming issue of the J Allergy Clin Immunol. 2008 Jul;122(1):133-8. Epub 2008 Jun 10, Dr. Kirsi M. Jarvinen, from Mount Sinai School of Medicine in New York, and colleagues evaluated epinephrine usage in children with food allergies by surveying the families of 413 patients.Overall, 78 children (median age = 4.5 years) were given epinephrine for a total of 95 reactions, the report indicates. Over 75% of these reactions involved peanut, tree nut, or cow's milk allergies.Twelve (13%) of the reactions required two doses of epinephrine and an additional 6 (6%) required three doses, the researchers found. Asthma was identified as a predictor of receiving multiple epinephrine doses, whereas the amount of food ingested and the delay in initial epinephrine treatment seemed to have no effect."Our survey performed in a highly selected patient population indicates that a significant number of respondents received a second dose of epinephrine," the authors conclude. "Prospective studies are needed to identify risk factors for severe anaphylaxis and to establish rational guidelines for prescribing multiple epinephrine autoinjectors for children with food allergy." (posted July 13th, 2008)

 

Availability of the epinephrine autoinjector at school in children with peanut allergy.

-This is the title of a publication in Ann Allergy Asthma Immunol. 2008 Jun;100(6):570-5, by Ben-Shoshan M, Kagan R, Primeau MN, Alizadehfar R, Verreault N, Yu JW, Nicolas N, Joseph L, Turnbull E, Dufresne C, St Pierre Y, Clarke A. The authors describe epinephrine autoinjector availability at school and determine factors that might affect autoinjector availability in children allergic to peanut.

Two hundred seventy-one children with peanut allergy living in Quebec were queried about their autoinjector. RESULTS: Four of 271 children diagnosed as having peanut allergy were not prescribed autoinjectors.

Forty-eight percent of the children did not carry the autoinjector with them at school. In 78.0% of those, the autoinjector was located in the nurse's or another school office, which was staffed by a full-time nurse only in 18.5%.

Of all the respondents, those administered epinephrine for a previous reaction, older children and those living only with their mother were more likely to carry the autoinjector with them at school.

Of children 7 years or older, those who experienced a severe reaction were more likely to carry their autoinjector.

CONCLUSIONS: Almost 50% of children allergic to peanut might experience a delay in anaphylaxis treatment due to limited access to their device. More education is required regarding the importance of a readily available autoinjector. (posted July 11th, 2008)

 

On the importance of having an epinephrine auto-injector with you at any age

-On July 4th, 2008 appeared the following article in the Everett, Washington Herald by Sharon Salyer, Man's death a stark reminder of food allergy risks, a reminder that peanut-allergic individuals must carry their epinephrine autoinjectors with them at all times, even as adults.

About 90 seconds after taking a bite out of a chocolate chip cookie at a friend's birthday party, a 30-year old man, with a history of peanut allergy collapsed. By chance, an Everett pulmonologist, a nurse and a medic were attending the party. They administered CPR until aid crews arrived. He died the next day after having been treated in the ER of a medical center. The chocolate chip cookie contained peanut butter. The young man decided not to carry an epinephrine auto-injector with him as an adult, instead trying to be vigilant about what he was eating and having an over-the-counter allergy medicine close at hand. (posted July 5th, 2008)

 

More on the recurrence of peanut allergy

After a passed oral challenge

-As reported and posted in part 1 of Peanut allergy: where do we stand? recurrent peanut allergy has been described in patients who have previously passed an oral food challenge (N Engl J Med 2002;347:1535-1536). It has been suggested that recurrent peanut allergy might be prevented by regular ingestion of peanut subsequent to passing an oral food challenge (J Allergy Clin Immunol 2004;114:1195-1201).

In Int Arch Allergy Immunol. 2008 Jul 2;147(3):260-262  Boyle RJ and Tang ML present a case that challenges this thinking by demonstrating that peanut allergy may recur during regular ingestion of significant doses of peanut protein. The case suggests that current practice cannot guarantee freedom from recurrent peanut allergy, and it is important that patients and their families are aware of this. (posted July 9th, 2008)

 

On the incidence and severity of future reactions

-Clark and Ewen have some interesting, and I think encouraging, statistics in their publication in the J Allergy Clin Immunol. 2008 Jun 27, entitled Good prognosis, clinical features, and circumstances of peanut and tree nut reactions in children treated by a specialist allergy center. To describe frequency and circumstances of reactions after the institution of a management plan, the severity and circumstances of worst reaction before diagnosis (index) and follow-up reactions were evaluated in a totoal of 785 children. Initial reactions were mild in 66% (516), moderate in 29% (224), and severe in 5% (45). 

         -Fourteen percent (114/785) had follow-up reactions (3% annual incidence rate). Ninety percent had the same/reduced severity grade, and 1 of 785 (0.1%) had a severe reaction.

         -Preschool children (n = 263) had a low incidence of reactions, and none were severe. There was a 3-fold reduction in injected epinephrine use from that used in the index reaction, required in 1 severe reaction, never twice; 14% (16/114) required no medication, 78% only oral antihistamines.

        -Accidental versus index (initial) reactions were 4-fold more likely to be a result of contact exposure rather than ingestion. Contact reactions were always mild. Most (53%) reactions occurred at home, 5% in school, 21% at other sites (21% not recorded). The nut was given by a parent/self in 69 (61%) reactions or teacher in 5 (4%).

CONCLUSION: With a comprehensive management plan, accidental reactions were uncommon and usually mild, most requiring little treatment; 99.8% self-treated appropriately and 100% effectively. (posted July 2nd, 2008)

 

-According to Ho, MH et al in their article Early clinical predictors of remission of peanut allergy in children published in the J Allergy Clin Immunol. 2008 Mar;121(3):731-6, Remission of peanut allergy can be predicted by low levels of IgE antibodies to peanut in the first 2 years of life or decreasing levels of IgE sensitization by the age of 3 years. (posted Nov 15th, 2008)

 

-In Curr Allergy Asthma Rep. 2009 Jan;9(1):57-63, Muñoz-Furlong A, Weiss CC have an article entitled  Characteristics of food-allergic patients placing them at risk for a fatal anaphylactic episode.   According to the authors, factors that place food-allergic patients at greater risk for a fatal anaphylactic episode include asthma; being a teen or young adult; peanut, tree nut, and seafood allergy; not carrying epinephrine; restaurant food; spending time in schools and child care settings; and lack of information from health care providers. Better education of patients and their families about managing their food allergy and high-risk situations can help to prevent future fatalities. (posted Jan. 11th, 2009)

 

More on prevalence of peanut allergy

-In the first part of this peanut allergy article, Dr Rhoda Kagan et al presented in 2003, in the section on 'Increase (?) in the prevalance and intensity of peanut allergy', Prevalence of peanut allergy in primary-school children in Montreal, Canada. The authors concluded that the prevalance had almost doubled in five years. Dr Mosha Ben-Shoshan presented the findings of a similar study at the annual AAAA&I meeting held in Philadelphia in March, 2008. Here's the April 11, 2008 intenet version report by Terry Murray of the Medical Post: AAAAI:

Peanut allergy prevalence rising slowly, if at all


From the annual meeting of the American Academy of Allergy, Asthma and Immunology held in Philadelphia.

Finding contradicts other studies that suggested dramatic increase

PHILADELPHIA | Five years ago, Montreal researchers turned up a surprisingly high prevalence of peanut allergy—1.5%—among school children they studied. At the time, two other prevalence studies—one done on the Isle of Wight and the second done in New York—showed rates around 0.5%, leading the Canadians to harbour some doubts about their finding.

Now, the researchers at McGill University have repeated their study and found peanut allergy prevalence of 1.7%, leading to more confidence in their original results—but new doubts about whether the prevalence is increasing.

The study, presented in a poster session of the AAAAI meeting here, suggested an increased prevalence of 33% in the intervening five years, but that finding was not statistically significant.

On followup, the U.K. and U.S. studies had shown a doubling in prevalence over five years.

In 2000 to 2002 and again in 2005 to 2007, the researchers, headed by Dr. Rhoda Kagan and Dr. Ann Clarke, administered questionnaires to the parents of kindergarten to Grade 3 children in public and private schools in Montreal. They asked about peanut allergy and followed up with testing (skin prick tests, IgE determinations and food challenges) for those with either a history of peanut allergy or who were uncertain.

For the most recent study, 5,157 parents responded, 93% of whom reported their child was tolerant to peanut, said Dr. Moshe Ben-Shoshan, the allergy fellow who presented the findings.

Of the remaining children, 231 underwent the full series of tests while the rest provided only partial information.

Data difficulties


Using a statistical technique called multiple imputation, the researchers were able to estimate prevalence for the children who provided only partial information and for the non-responders, Dr. Ben-Shoshan said.

Those results showed a 1.65% prevalence for the complete responders, 2.07% for the full and partial responders and 1.78% after adjusting for missing data.

When comparing those prevalences with the figures for the same groups five years ago, the absolute differences between the prevalence in 2005 to 2007 and 2000 to 2002 were 0.15% among those providing complete data and 0.32% for those providing full and partial data. However, the differences were not statistically significant because the 95% confidence intervals overlapped 1.0.

“Although we would like to show (the increase) clearly for the full responders, it’s very difficult because you can’t always get 100% participation,” Dr. Ben-Shoshan said in an interview. “It’s only for the biggest group that we have a significant result.”

So while the study suggests an increased prevalence of about 33% over five years, “our wide confidence intervals preclude definitive conclusions.”

While it’s possible the increase in peanut allergy could have plateaued, it’s reassuring that even if the increase is 33%, it’s not as dramatic as the 50% increase suggested by the U.K. and U.S. studies, Dr. Ben-Shoshan added.

(posted June 28th, 2008)

 

- In the April, 2009 issue J Allergy Clin Immunol., Ann Clarke, Ben-Shoshan M, Kagan RS et al. have a publication entitled Is the prevalence of peanut allergy increasing? A 5-year follow-up study in children in Montreal.

Studies suggest that peanut allergy prevalence might be increasing, but these results have not yet been substantiated. Questionnaires regarding peanut ingestion were administered to parents of children in randomly selected kindergarten through grade 3 classrooms between December 2000 and September 2002 and between October 2005 and December 2007. Respondents were stratified as (1) peanut tolerant, (2) never/rarely ingest peanut, (3) convincing history of peanut allergy, or (4) uncertain history of peanut allergy. Children in group 3 with positive skin prick test responses were considered to have peanut allergy. Children in groups 2 and 4 with positive skin prick test responses had peanut-specific IgE levels measured, and if the value was less than 15 kU/L, an oral peanut challenge was performed.

RESULTS: Of 8,039 children surveyed in 2005-2007, 64.2% of parents responded. Among those providing complete data, the prevalence was 1.63% in 2005-2007 versus 1.50% in 2000-2002. The differences between the prevalences in 2005-2007 and 2000-2002 were 0.13%...

CONCLUSIONS: This is the first North American study to document temporal trends in peanut allergy prevalence by corroborating history with confirmatory tests. The results suggest a stable prevalence... (posted April 13th, 2009

  -As a follow-up to this posting, at the annual Bram Rose Conference of the AAIQ (Association of Allergists and Immunologists of Quebec) held in Quebec City, Qué. May 1st and 2nd, 2009, Dr Ann Clarke (co-author of the above publication) presented Peanut Allergy: Demonized or Trivialized?

-Although not being able to answer this question conclusively, analyzing the recent studies leading to the one posted above, and citing comments published in the last couple months, including the one by Dr Nicholas A. Christakis, a Harvard professor of medical sociology, in the British Medical Journal entitled This Allergies Hysteria is Just Nuts, the trend seems to be leaning towards the latter. In the words of professor Christakis "there is a gross over-reaction to the magnitude of the threat" posed by food allergies, particularly nut allergies. Professor Christakis said the issue was not whether nut allergies existed or whether they could occasionnaly be serious. Nor was the issue whether reasonable preventative steps should be made for the few children who had documented serious allergies. "The issue is what accounts for the extreme responses to nut allergies." He adds, "Well intentioned efforts to reduce exposure to nuts actually fan the flames, since they signal to parents that nuts are a clear and present danger". He concluded that "these responses were extreme and had many of the hallmarks of mass psychogenic illness (MPI), previously known as epidemic hysteria." The BBC followed up on these comments on Dec. 10th, 2008, after a reported incident where a peanut on the floor of a US school bus led to evacuation and decontamination for fear it might have affected the 10-year-old passengers. The BBC added that John Collard, nurse consultant and clinical director of Allergy UK, said people in Britain were also going overboard in their reactions to allergies. "The risk has been blown out of all proportion."

-There were many on line responses published in the British Medical Journal following Dr Christakis's comments, and here are some excerpts:

Wendy McLean: "Professor Christakis writes in the hysterical fashion he is criticising. This is good for newspaper publicity but well below the normal BMJ standard..."

Jonathan Hourihane, M.D. "Christakis's commentary smacks of nimbyisim (Not In My Back Yard-ism) because he has been inconvenienced by his school's response to the issue of sealed tins of festive nuts. If his own child  were nut allergic I imagine his response would have been different. I agree that the institutions' actions...appear to be over-elaborate. However the use of emotive language like 'evacuation' and 'decontamination' is not helpful."

Many comments were in agreement:

"I agree with Nicholas Christakis. Sometimes advice given about allergies can be a bit overenthusiastic (to say the least)."

"Whilst acknowledging that allergies can be life-threatening for some, I think health professionals (and other people in authority) really ought to consider the whole thing about risk perception and management and not make us all afraid of our own shadows".

"Our thanks are due to Prof Christakis for his blast of common sense on this issue."

-TIME magazine followed up on Dr Christakis' comments on Feb. 26th, 2009 with Why We're Going Nuts Over Nut Allergies

I would just like to add that I agree totally with Dr Christakis (JW)

(posted May 16th, 2009)

- In Allergy. 2010 Jan;65(1):103-108, Venter C, Hasan Arshad S, Grundy J, Pereira B, Bernie Clayton C, Voigt K, Higgins B, Dean T. have a publication entitled Time trends in the prevalence of peanut allergy: three cohorts of children from the same geographical location in the UK. This article investigated the prevalence of peanut allergy in three cohorts of children born in the same geographical location, Isle of Wight, UK and seeks to determine whether the prevalence of peanut allergy has changed between 1994 and 2004.

Conclusions: Our data from three cohorts of 3- to 4-year-old children born in the same geographical area shows that peanut allergy prevalence has changed over time. Peanut sensitization and reported allergy in children born in 1994-1996 increased from 1989 but seems to have stabilized or slightly decreased since the late 1990s, although not significant. (posted Jan 19th, 2010)

-In Br J Nutr. 2010 Jan 26:1-9. Thompson RL, Miles LM, Lunn J, Devereux G, Dearman RJ, Strid J, Buttriss JL have a publication entitled Peanut sensitisation and allergy: influence of early life exposure to peanuts.


According to the abstract: The aim of the present systematic review was to evaluate the influence of early life exposure (maternal and childhood) to peanuts and the subsequent development of sensitisation or allergy to peanuts during childhood...Six human studies were identified: two randomised controlled trials, two case-control studies and two cross-sectional studies..... Overall, the evidence reviewed was heterogeneous...

The systematic review of human studies and narrative expert-led reviews of animal studies do not provide clear evidence to suggest that either maternal exposure, or early or delayed introduction of peanuts in the diets of children, has an impact upon subsequent development of sensitisation or allergy to peanuts.

Results from some animal studies (and limited evidence from human subjects) suggest that the dose of peanuts is an important mediator of peanut sensitisation and tolerance; low doses tend to lead to sensitisation and higher doses tend to lead to tolerance.

In the same journal, Minshall EM and Warner JO have an artilce they tiltled Early peanut exposure: poison or panacea? (posted Jan. 27th, 2010) ......more to come.


- In the J Allergy Clin Immunol. 2010 Jan;125(1):191-197.e13. Nicolaou N. et al have a publication called Allergy or tolerance in children sensitized to peanut: Prevalence and differentiation using component-resolved diagnostics.


BACKGROUND: Not all peanut-sensitized children develop allergic reactions on exposure.

OBJECTIVE: To establish by oral food challenge the proportion of children with clinical peanut allergy among those considered peanut-sensitized by using skin prick tests and/or IgE measurement, and to investigate whether component-resolved diagnostics using microarray could differentiate peanut allergy from tolerance.

METHODS: Within a population-based birth cohort, we ascertained peanut sensitization by skin tests and IgE measurement at age 8 years. Among sensitized children, we determined peanut allergy versus tolerance by oral food challenges...

RESULTS: Of 933 children, 110 (11.8%) were peanut-sensitized. Nineteen were not challenged (17 no consent). Twelve with a convincing history of reactions on exposure, IgE >/=15 kUa/L and/or skin test >/=8mm were considered allergic without challenge. Of the remaining 79 children who underwent challenge, 7 had >/=2 objective signs and were designated as having peanut allergy. We estimated the prevalence of clinical peanut allergy among sensitized subjects as 22.4%...

CONCLUSION: The majority of children considered peanut-sensitized on the basis of standard tests do not have peanut allergy. (posted Jan 30th, 2010)

- In the J Allergy Clin Immunol. 2010 May 6, Ben-Shoshan M, Harrington DW, Soller L, Fragapane J, Joseph L, St Pierre Y, Godefroy SB, Elliot SJ, Clarke AE, have a publication entitled A population-based study on peanut, tree nut, fish, shellfish, and sesame allergy prevalence in Canada.


BACKGROUND: Recent studies suggest an increased prevalence of food-induced allergy and an increased incidence of food-related anaphylaxis. However, prevalence estimates of food allergies vary considerably between studies. OBJECTIVES: To determine the prevalence of peanut, tree nut, fish, shellfish, and sesame allergy in Canada. METHODS: Using comparable methodology to Sicherer et al in the United States in 2002, we performed a cross-Canada, random telephone survey. Food allergy was defined as perceived (based on self-report), probable (based on convincing history or self-report of physician diagnosis), or confirmed (based on history and evidence of confirmatory tests).

RESULTS: Of 10,596 households surveyed in 2008 and 2009, 3666 responded (34.6% participation rate), of which 3613 completed the entire interview, representing 9667 individuals. The prevalence of perceived peanut allergy was 1.00%, tree nut 1.22%, fish, 0.51%, shellfish, 1.60%, and sesame, 0.10%. The prevalence of probable allergy was 0.93%, 1.14%, 0.48%, 1.42% and 0.09%, respectively. Because of the infrequency of confirmatory tests and the difficulty in obtaining results if performed, the prevalence of confirmed allergy was much lower.

CONCLUSION: This is the first nationwide Canadian study to determine the prevalence of severe food allergies. Our results indicate disparities between perceived and confirmed food allergy that might contribute to the wide range of published prevalence estimates. (posted May 25th, 2010)

- In the J Allergy Clin Immunol. 2010 May 10, Sicherer SH, Muñoz-Furlong A, Godbold JH, Sampson HA have an article entitled US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up.

BACKGROUND: Allergy to peanuts and tree nuts (TNs) is the leading cause of fatal allergic reactions in the United States, and the prevalence appears to be increasing. OBJECTIVES: We sought to determine the US prevalence of self-reported peanut, TN, and sesame allergy in 2008 and compare results with comparable surveys conducted in 1997 and 2002. METHODS: A nationwide, cross-sectional, random telephone survey for peanut and TN allergy was conducted with a previously used questionnaire, with additional questions about sesame.

RESULTS: A total of 5,300 households (13,534 subjects) were surveyed (participation rate, 42% vs 52% in 2002 and 67% in 1997). Peanut allergy, TN allergy, or both was reported by 1.4% of subjects... compared with 1.2% in 2002 and 1.4% in 1997. For adults, the prevalence was 1.3%...which was not significantly different from prior surveys. However, the prevalence of peanut or TN allergy for children younger than 18 years was 2.1%... compared with 1.2% in 2002...and 0.6% in 1997... The prevalence of peanut allergy in children in 2008 was 1.4%... compared with 0.8% in 2002...and 0.4% in 1997.... The prevalence of childhood TN allergy increased significantly across the survey waves (1.1% in 2008, 0.5% in 2002, and 0.2% in 1997). Sesame allergy was reported by 0.1%...

CONCLUSIONS: Although caution is required in comparing surveys, peanut allergy, TN allergy, or both continue to be reported by more than 1% of the US population (eg, >3 million subjects) and appear to be increasingly reported among children over the past decade. Sesame allergy is reported much less commonly. (posted May 25th, 2010)

-In the J Allergy Clin Immunol. 2011 Jan 12, Kotz D, Simpson CR, Sheikh A. have an article entitled
Incidence, prevalence, and trends of general practitioner-recorded diagnosis of peanut allergy in England, 2001 to 2005.


METHODS: Version 10 of the QRESEARCH database was used with data from 2,958,366 patients who were registered with 422 United Kingdom general practices in the years 2001 to 2005. The primary outcome was a recording of clinician-diagnosed peanut allergy.

 

RESULTS: The age-sex standardized incidence rate of peanut allergy in 2005 was 0.08 per 1000 person-years... and the prevalence rate was 0.51 per 1000 patients... This translated into an estimated 4000 incident cases ... and 25,700 prevalent cases... of GP-recorded diagnosis of peanut allergy in England in 2005. During the study period, the incidence rate of peanut allergy remained fairly stable, whereas the prevalence rate doubled. In those under 18 years of age, the crude lifetime prevalence rate was higher in males than females. A significant inverse relationship between prevalence and socioeconomic status was found.

CONCLUSION: These data on GP-recorded diagnosis of peanut allergy from a large general practice database suggest a much lower prevalence in peanut allergy than has hitherto been found. This difference may in part be explained by underrecording of peanut allergy in general practice. Further research is needed to assess the true frequency of peanut allergy in the population and whether there has been a true increase in recent years. (posted Jan. 26th, 2011)

- In Clin Exp Allergy. 2011 Mar 24. there is an article by Johannsen H, Nolan R, Pascoe EM, Cuthbert P, Noble V, Corderoy T, Franzmann A, Loh R, Prescott, SL, entitled, Skin prick testing and peanut-specific IgE can predict peanut challenge outcomes in preschoolchildren with peanut sensitization.


To determine the utility of skin prick tests(SPT) and fluorescent-enzyme immunoassays (FEIA) for identifying either peanut allergy or tolerance in preschool children with peanut sensitization, the authors evaluated 49 children sensitized to peanut (SPT 2mm or peanut specific IgE 0.35 kU/L) but unknown clinical reactivity, with graded open peanut challenges reaching a total of 11 gms...

Results: Forty-nine percent (24/49) of children had positive challenges. An SPT of >7 mm on the day of challenge predicted a positive challenge with a sensitivity of 83% and a negative predictive value (NPV) of 84%. An FEIA of >2.0 kU/L showed a sensitivity of 79% and an NPV of 80%. Predicting challenge outcome from a combination of SPT and FEIA (SPT >7 and/or FEIA >2 is positive) increased sensitivity to 96% and NPV to 95%.

Conclusion and Clinical Relevance At least half of preschoolchildren with peanut sensitization and no antecedent history of peanut ingestion can tolerate peanuts. A SPT<7 mm and FEIA<2 kU/L identify children most likely to tolerate peanut, with only a 5% likelihood of failing an oral challenge. This study assists clinicians considering challenges in very young peanut-sensitized children. (posted April 16th, 2011)

 

 

More on peanut sensitization

 

Possible routes

-In the J Allergy Clin Immunol. 2009 Nov;124(5):1039-46, López-Expósito I, Song Y, Järvinen KM, Srivastava K, Li XM report Maternal peanut exposure during pregnancy and lactation reduces peanut allergy risk in offspring.
Maternal allergy is believed to be a risk factor for peanut allergy (PNA) in children. However, there is no direct evidence of maternal transmission of PNA susceptibility, and it is unknown whether maternal peanut exposure affects the development of PNA in offspring. The authors show for the first time maternal transmission of susceptibility to first-exposure peanut reactions and active peanut sensitization. Their conclusion: Low-dose peanut exposure during pregnancy and lactation reduced this risk. (posted Nov 10th, 2009)

-In the J Investig Allergol Clin Immunol. 2010;20(4):289-94, DesRoches A, Infante-Rivard C, Paradis L, Paradis J, Haddad E. have an article entitled Peanut allergy: is maternal transmission of antigens during pregnancy and breastfeeding a risk factor?
 

OBJECTIVE: To determine whether the consumption of peanuts during pregnancy and breastfeeding is a risk factor for peanut allergy in infants. 403 infants were enroled in a case-control study. The cases were infants aged 18 months or less with a diagnosis of peanut allergy based on a history of clinical reaction after exposure to peanuts and the presence of peanut-specific immunoglobulin E. Controls were age-matched infants with no known clinical history or signs of atopic disease. The mothers of the children filled out a detailed questionnaire about maternal diet during pregnancy and breastfeeding, the infant's diet, the presence of peanut products in the infant's environment, and family history of atopy.

RESULTS: The mean (SD) age of cases was 1.23 (0.03) years. The groups were comparable in terms of the rate and duration of breastfeeding. However, the reported consumption of peanuts during pregnancy and breastfeeding was higher in the case group and associated with an increased risk of peanut allergy in offspring. Overall, the infants with peanut allergy did not seem to be more exposed to peanut products in their environment than the controls.

CONCLUSION: Early exposure to peanut allergens, whether in utero or through human breast milk, seems to increase the risk of developing peanut allergy. (posted Sept. 29th, 2010)

- By the same authors in J Allergy Clin Immunol. 2011 May 10. : Peanut allergy and the impact of maternal consumption during pregnancy and breast-feeding. (posted May 15th, 2011)

- In the July 2011 of the J Allergy Clin Immunol. the authors have a letter to the editor, discussing the publication by Sicher et al (posted just below) and their findings, in which they underline their belief that maternal consumption of peanut during breast-feeding cannot be discarded as a risk factor at this time. (posted Sept 24th, 2011)

-In the J Allergy Clin Immunol. 2010 Oct 27, Sicherer SH, Wood RA, Stablein D, Lindblad R, Burks AW, Liu AH, Jones SM, Fleischer DM, Leung DY, Sampson HA have an article entitled Maternal consumption of peanut during pregnancy is associated with peanut sensitization in atopic infants.

Abstract:

BACKGROUND: Peanut allergy is typically severe, lifelong, and prevalent. OBJECTIVE: To identify factors associated with peanut sensitization.

METHODS: We evaluated 503 infants 3 to 15 months of age (mean, 9.4 months) with likely milk or egg allergy but no previous diagnosis of peanut allergy. A total of 308 had experienced an immediate allergic reaction to cow's milk and/or egg, and 204 had moderate to severe atopic dermatitis and a positive allergy test to milk and/or egg. A peanut IgE level ≥5 kU(A)/L was considered likely indicative of peanut allergy.

RESULTS: A total of 140 (27.8%) infants had peanut IgE levels ≥5 kU(A)/L. Multivariate analysis including clinical, laboratory, and demographic variables showed frequent peanut consumption during pregnancy... Frequency of peanut consumption during pregnancy and breast-feeding showed a dose-response association with peanutIgE ≥5 kU(A)/L, but only consumption during pregnancy was a significant predictor. Among 71 infants never breast-fed, frequent consumption of peanut during pregnancy was strongly associated with peanut Ig≥5 kU(A)/L...

CONCLUSION: In this cohort of infants with likely milk or egg allergy, maternal ingestion of peanut during pregnancy was strongly associated with a high level of peanut sensitization. (posted Nov 3d, 2010)

- In Allergy Asthma Clin Immunol. 2011 Oct 4;7(1):17, Binkley KE, Leaver C, Ray JG published Antenatal risk factors for peanut allergy in children

Prenatal factors may contribute to the development of peanut allergy. The authors evaluated the risk of childhood peanut allergy in association with pregnancy exposure to Rh immune globulin, folic acid and ingestion of peanut-containing foods. They conducted a web-based case-control survey using the Anaphylaxis Canada Registry, a pre-existing database of persons with a history of anaphylaxis. A total of 1300 case children with reported peanut allergy were compared to 113 control children with shellfish allergy. All were evaluated for maternal exposure in pregnancy to Rh immune globulin and folic acid tablet supplements, as well as maternal avoidance of dietary peanut intake in pregnancy.

RESULTS:
Receipt of Rh immune globulin in pregnancy was not associated with a higher risk of peanut allergy (odds ratio [OR] 0.86, 95% confidence interval, nor was initiation of folic acid tablet supplements before or after conception. Complete avoidance of peanut-containing products in pregnancy was associated with a non-significantly lower risk of peanut allergy.

CONCLUSION:
The risk of childhood peanut allergy was not modified by the following common maternal exposures in pregnancy: Rh immune globulin, folic acid or peanut-containing foods. Clinical implications: Rh immune globulin, folic acid supplement use and peanut avoidance in pregnancy have yet to be proven to modulate the risk of childhood anaphylaxis to peanuts. Capsule Summary: Identification of prenatal factors that contribute to peanut allergy might allow for prevention of this life-threatening condition. This article explores the role of three such factors. (posted Nov 1st, 2011)

-Gorgievska Sukarovska B, Lipozenci? J, Stajminger G have a publication in Acta Dermatovenerol Croat. 2007;15(4):269-71 entitled What should we know about hypersensitivity to peanuts in topical preparations. In their abstract, which is quite long, they give a thorough summary of peanut allergy in many respects, including topical sensitization (skin contact with preparations containing peanut oil. Here is part of the abstract:

'A retrospective British study demonstrated the association between type I hypersensitivity reaction to peanut and previous skin exposure, i.e. use of topical preparations based on peanut oil. It is considered that as many as 95% of individuals with peanut hypersensitivity have a history of previous exposure to topical preparations containing peanut oil, especially in the first six months of life. The study does not specify the products and their amount used, etc. ...

Topical preparations containing peanut oil or soybean oil should not be used in individuals with known peanut and soybean allergy.

In conclusion, peanut sensitization is an important and increasing clinical problem due to the severe allergic manifestations that may threaten the life of sensitized individuals. Topical preparations containing peanut oil have proved efficient in the treatment of very dry and damaged skin in children and adults with atopic diseases. Epicutaneous sensitization is one of the potential routes of sensitization; therefore great caution is warranted in individuals with allergic predisposition. (posted Feb 17th, 2008)

-Koplin J et al in their study published in the J Allergy Clin Immunol. 2008 Jun;121(6):1455-9 conclude that Soy consumption is not a risk factor for peanut sensitization. (posted Nov. 15th, 2008)

-In the J Allergy Clin Immunol. 2009 Feb;123(2):424-5.Fox AT, Sasieni P, du Toit G, Syed H, Lack G. have a publication called Household peanut consumption as a risk factor for the development of peanut allergy.

Most children with peanut allergy (PA) react on first known oral exposure to peanut. Recent data suggest cutaneous exposure as a route of sensitization. Questionnaires were administered to children with PA and to high-risk controls (with egg allergy) and controls without allergy. Questionnaires were completed before subjects were aware of their PA status, avoiding recall bias. Questionnaires recorded maternal peanut consumption during pregnancy, breast-feeding, and the first year of life. Peanut consumption was determined among all household members, allowing quantification of environmental household exposure (household peanut).

RESULTS: Median weekly household peanut in the 133 PA cases was significantly elevated (18.8 g) compared with 150 controls without allergy (6.9 g) and 160 high-risk controls (1.9 g). A dose-response relationship was observed between environmental (nonoral) peanut exposure and the development of PA, which was strongest for peanut butter. Early oral exposure to peanut in infants with high environmental peanut exposure may have had a protective effect against the development of PA.

CONCLUSIONS: High levels of environmental exposure to peanut during infancy appear to promote sensitization, whereas low levels may be protective in atopic children. No effect of maternal peanut consumption during pregnancy or lactation is observed, supporting the hypothesis that peanut sensitization occurs as a result of environmental exposure. (posted Feb 14th, 2009)

 
 

Link between soy lecithin and peanuts (?)

- Béliveau S, Gaudreault P, Goulet L, Primeau MN, Marcoux D have a publication entitiled Type I hypersensitivity in an asthmatic child allergic to peanuts: was soy lecithin to blame? J Cutan Med Surg. 2008 Jan-Feb;12(1):27-30. Here's their abstract:

BACKGROUND: Soy lecithin is widely used as an emulsifier, not only in topical skin care products but also in various drugs administered either topically, orally, or intravenously or by inhalation. Patients strongly allergic to soy and/or peanuts can develop an anaphylactic reaction when exposed to soy lecithin. METHOD: We report a 3-year-old asthmatic boy, allergic to peanuts, who was treated at the emergency department for an exacerbation of asthma following an upper respiratory tract infection. Within an hour after receiving the second of two inhalations of an ipratropium bromide (Atrovent) metered dose inhaler, he developed respiratory distress and generalized urticaria, an adverse event that regressed within 48 hours of withdrawal of the suspected drug. Soy lecithin, contained as an excipient in the metered dose inhaler, was strongly suspected of being responsible for this reaction. CONCLUSION: Drug products containing soy lecithin can cause severe allergic reactions in patients allergic to peanuts or soy. Physicians should be aware that adverse drug reactions can be due to both the active medical component and the excipient ingredients. (posted Feb 19th, 2008)

 

Link between lupin and peanut

-Shaw J, Roberts G, Grimshaw K, White S, Hourihane J in Allergy. 2008 Mar;63(3):370-3 have an article entitled Lupin allergy in peanut-allergic children and teenagers.

Peanut-allergic subjects ( <18 years) were recruited that either had a convincing history of peanut allergy with diagnostic peanut skin prick test (SPT) or specific-immunoglobulin E (IgE) results or a positive food challenge. Control subjects were atopic but not peanut-allergic. All subjects had SPT to peanut and lupin. Sensitized subjects were offered a randomized, double-blind, placebo-controlled lupin challenge. Lupin allergy was defined as objective immediate hypersensitivity reaction at food challenge.

Results: Forty-seven peanut-allergic children and 46 atopic controls were recruited. Sixteen peanut-allergic children were sensitized to lupin [34%, 95% confidence interval (CI): 21-49%]. Nine were challenged to lupin. Two reacted (itchy mouth and urticaria; itchy mouth and 20% drop in peak expiratory flow rate) giving a minimum prevalence of lupin allergy in peanut-allergic children of 4.0% (95% CI: 1-15%). Atopic controls were significantly (P = 0.001) less likely to be sensitized to lupin (4%, 95% CI: 1-15%) and had smaller wheals and serum-specific IgE results. None of the atopic controls reacted on lupin challenge, giving a rate of allergy in the atopic controls of 0% (95% CI: 0-8%).

CONCLUSIONS: A small but significant number of children with peanut allergy are allergic to lupin. Sensitization to lupin is much rarer in nonpeanut-allergic atopic subjects.

 

-In Acta Paediatr. 2008 Jan;97(1):91-5. Epub 2007 Dec 10, Lindvik H, Holden L, Løvik M, Cvancarova M, Halvorsen R. have a publication called Lupin sensitization and clinical allergy in food allergic children in Norway. Here's part of their abstract:

Thirty-five children with food allergy were evaluated with skin prick test (SPT) and analysis of serum-specific IgE to lupin, peanut, pea and soy. The children with positive SPTs to lupin were offered oral food challenges with lupin flour.

Results: Fifteen children (43%) had positive SPT and 17 children (49%) had serum-specific IgE to lupin. Ten SPT-positive children underwent oral food challenges and one experienced an allergic reaction to lupin flour. This child was one of six challenged children with IgE antibodies to peanut >15 kU(A)/L. There was a strong relationship between positive SPT to lupin flour and positive SPT to soy and between positive SPT to lupin and specific IgE to soy, pea and peanut.

Conclusions: Children with sensitization to lupin are not likely to have a clinical lupin allergy. Avoidance of lupin on the basis of lupin sensitization or peanut allergy would lead to unnecessarily strict diets. Food challenge is currently necessary to diagnose lupin allergy. (posted Feb. 19th, 2008)

-In the Eur Ann Allergy Clin Immunol. 2009 Feb;41(1):17-22. Gayraud J, Mairesse M, Fontaine JF, Thillay A, Leduc V, Rancé F, Parisot L, Moneret-Vautrin DA. have a publication entitiled The prevalence of sensitization to lupin flour in France and Belgium: a prospective study in 5,366 patients, by the Allergy Vigilance Network.

CONCLUSION: The relative frequency of latent sensitisation to lupin in patients of all ages presenting with atopic disease is a new factor indicating the likelihood of an increase in primary food allergies to lupin flour. This justifies the recent decision requiring mandatory labelling of lupin, and shows the need to inform consumers who may be unaware that this ingredient is being used increasingly. Sensitization to lupin should be searched by prick-tests in any case of peanut allergy. Prick-test to lupin may be valuable whenever a food allergy is suspected when no current food allergens have been identified. (posted June 6th, 2009)

 

Re peanut-nut allergy and coconut

- Following the posting in 1999 of a study re a link between peanut-nut allergy and coconut that concluded that coconut allergy in rarely associated, at the March 2009 AAAA&I annual meeting held in Washington, DC., Rangsithienchai et al. reported on their study on this possible link. Their conclusion was that there is no evidence of increased coconut allergy in children allergic to tree nuts or peanuts. (posted March 22nd, 2009)

Re peanut-nut allergy and sesame

- According to a presentation by Stutius LM et al. at the annual meeting of the AAAA&I held in Washington, DC , March 2009, entitled 'Characterizing the Relationship Between Peanut and Sesame Allergy in Children', children with peanut sensitivity are more likely to be sensitized to sesame. However, there does not appear to be a significant relationship between reported history of clinical reaction to peanut and sesame. (posted Mar 24th, 2009)

 

Tolerance vs sensitization

-In Pediatr Allergy Immunol. 2008 Feb 9, Prescott SL et al wrote The importance of early complementary feeding in the development of oral tolerance: Concerns and controversies. Here is their abstract:


Rising rates of food allergies in early childhood reflect increasing failure of early immune tolerance mechanisms. There is mounting concern that the current recommended practice of delaying complementary foods until 6 months of age may increase, rather than decrease, the risk of immune disorders. Tolerance to food allergens appears to be driven by regular, early exposure to these proteins during a 'critical early window' of development. Although the timing of this window is not clear in humans, current evidence suggests that this is most likely to be between 4 and 6 months of life and that delayed exposure beyond this period may increase the risk of food allergy, coeliac disease and islet cell autoimmunity. There is also evidence that other factors such as favourable colonization and continued breastfeeding promote tolerance and have protective effects during this period when complementary feeding is initiated. This discussion paper explores the basis for concern over the current recommendation to delay complementary foods as an approach to preventing allergic disease. It will also examine the growing case for introducing complementary foods from around 4 months of age and maintaining breastfeeding during this early feeding period, for at least 6 months if possible. (posted Feb 20th, 2008)

-In Arch Pediatr. 2008 Apr;15(4):431-42, Chouraqui JP et al in Feeding during the first months of life and prevention of allergy recommend: Exclusive breastfeeding is recommended until the age of 6 months. The elimination from the mother's diet of major food allergens potentially transmitted via breast milk may be indicated on an individual basis, except for peanut, which is systematically retrieved. In the absence of breastfeeding, prevention consists in feeding at-risk newborns until the age of 6 months with a hypoallergenic formula. Soy based formulae are not recommended for allergy prevention. Complementary feeding should not be started before the age of 6 months. Introduction of egg and fish into the diet can be made after 6 months but the introduction of potent food allergens (kiwi, celery, crustaceans, seafood, nuts, especially tree nuts and peanuts) should be delayed after 1 year. This preventive policy seems partially efficacious on early manifestations of allergy but does not restrain the allergic march, especially in its respiratory manifestations. Probiotics, prebiotics as well as n-3 fatty polyunsaturated acids have not yet demonstrated any definitive protective effect. (posted Nov. 15th. 2008)

 

-In Pediatrics. 2008 Jul;122(1):e115-22, Snijders BE et al have a publication called Age at first introduction of cow milk products and other food products in relation to infant atopic manifestations in the first 2 years of life: the KOALA Birth Cohort Study. Their results: More delay in introduction of cow milk products was associated with a higher risk for eczema. In addition, a delayed introduction of other food products was associated with an increased risk for atopy development at the age of 2 years. Exclusion of infants with early symptoms of eczema and recurrent wheeze (to avoid reverse causation) did not essentially change our results.

DISCUSSION: Delaying the introduction of cow milk or other food products may not be favorable in preventing the development of atopy. (posted Nov 15th, 2008)

-Du Toit G et al, have an article in J Allergy Clin Immunol. 2008 Nov;122(5):984-91, Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy.

BACKGROUND: Despite guidelines recommending avoidance of peanuts during infancy in the United Kingdom (UK), Australia, and, until recently, North America, peanut allergy (PA) continues to increase in these countries.

OBJECTIVE: We sought to determine the prevalence of PA among Israeli and UK Jewish children and evaluate the relationship of PA to infant and maternal peanut consumption.

METHODS: A clinically validated questionnaire determined the prevalence of PA among Jewish schoolchildren (5171 in the UK and 5615 in Israel). A second validated questionnaire assessed peanut consumption and weaning in Jewish infants (77 in the UK and 99 in Israel).

 

RESULTS: The prevalence of PA in the UK was 1.85%, and the prevalence in Israel was 0.17%... Peanut is introduced earlier and is eaten more frequently and in larger quantities in Israel than in the UK. The median monthly consumption of peanut in Israeli infants aged 8 to 14 months is 7.1 g of peanut protein, and it is 0 g in the UK. The median number of times peanut is eaten per month was 8 in Israel and 0 in the UK.

CONCLUSIONS: We demonstrate that Jewish children in the UK have a prevalence of PA that is 10-fold higher than that of Jewish children in Israel. This difference is not accounted for by differences in atopy, social class, genetic background, or peanut allergenicity. Israeli infants consume peanut in high quantities in the first year of life, whereas UK infants avoid peanuts. These findings raise the question of whether early introduction of peanut during infancy, rather than avoidance, will prevent the development of PA. (posted Nov. 15th, 2008)

-Wennergren G in Acta Paediatr. 2009 May 8. published What if it is the other way around? Early introduction of peanut and fish seems to be better than avoidance. Here's the abstract:

For many years, the advice to prevent food allergy was to postpone the introduction of allergens like egg, fish and peanut. However, elimination of food allergens during pregnancy and infancy failed to prevent food allergy. Instead, several studies indicate that early introduction of food like fish and peanuts may be beneficial. The most compelling illustration of this has been presented for peanuts. The prevalence of peanut allergy is lower in children in Israel than in the UK, despite introduction of peanut during infancy in Israel. Other studies have reported that early introduction of fish reduced the risk of allergic sensitization and allergic diseases like eczema.   Conclusion: Early introduction rather than avoidance may be a better strategy for the prevention of food allergy. The mechanism may be that early introduction of food allergens during infancy might induce tolerance, thereby preventing the development of allergy. (posted June 9th, 2009)

- In Pediatrics 2009 Dec 7. a Finnish study was published entitled Age at the Introduction of Solid Foods During the First Year and Allergic Sensitization at Age 5 Years.

Objective: The goal was to examine the relationship between age at the introduction of solid foods during the first year of life and allergic sensitization in 5-year-old children. Methods: The authors studied 994 children with HLA-conferred susceptibility to type 1 diabetes mellitus for whom information on breastfeeding, age at the introduction of solid foods, and allergen-specific immunoglobulin E levels at 5 years was available. The association between age at the introduction of solid foods and allergic sensitization was analyzed by using logistic regression.

Results: The median duration of exclusive breastfeeding was 1.8 months (range: 0-10 months). After adjustment for potential confounders, late introduction of potatoes (>4 months), oats (>5 months), rye (>7 months), wheat (>6 months), meat (>5.5 months), fish (>8.2 months), and eggs (>10.5 months) was significantly directly associated with sensitization to food allergens. Late introduction of potatoes, rye, meat, and fish was significantly associated with sensitization to any inhalant allergen....

Conclusion: Late introduction of solid foods was associated with increased risk of allergic sensitization to food and inhalant allergens. (posted Dec. 28th, 2009)

-In the J Allergy Clin Immunol. 2011 Mar 31, Joseph CL, Ownby DR, Havstad SL, Woodcroft KJ, Wegienka G, Mackechnie H, Zoratti E, Peterson EL, Johnson CC have an article entitled Early complementary feeding and risk of food sensitization in a birth cohort.


BACKGROUND: Exposure to solid food or cow's milk (complementary food) before age 4 months may confer immune protection (tolerance) or detriment (allergy).

OBJECTIVE: We explored the relationship between introduction of complementary food <4 months and IgE to egg, milk, and peanut allergen at 2 years in the Wayne County Health, Environment, Allergy and Asthma Longitudinal Study birth cohort of Detroit, Mich.

METHODS: At infant ages 1, 6, and 12 months, mothers were interviewed about feeding practices. Blood samples were collected at age 2 to 3 years to assess sensitization (IgE ≥ 0.35 IU/mL) to egg, milk, or peanut.

RESULTS: For the 594 maternal-infant pairs analyzed, maternal mean age was 29.7 years, and 60.6% self-reported as African American or black. Infant exposure to complementary food <4 months was reported by 39.7% of mothers. IgE ≥0.35 IU/mL for egg, milk, or peanut allergen at age 2 years was observed in 23.9% (95% CI, 20.5% to 27.6%), 30.6% (26.9% to 34.5%), and 11.4% (8.9% to 14.3%) of children, respectively. The association between early feeding and sensitization was modified by parental history of asthma or allergy. In multivariable analysis, early feeding reduced the risk of peanut sensitization among children with a parental history (adjusted odds ratio, 0.2 [95% CI, 0.1-0.7]; P = .007). The relationship also became significant for egg when a cutoff for IgE of ≥0.70 IU/mL was used (adjusted odds ratio, 0.5 [95% CI, 0.3-0.9]; P = .022).

CONCLUSION: In this cohort, complementary food introduced <4 months was associated with a reduced risk of peanut (and perhaps egg) sensitization by age 2 to 3 years, but only for children with a parental history of asthma or allergy. (posted April 15th, 2011)

 

More on desensitization (immunotherapy) for peanut allergy

- In Allergy. 2009 Feb 17, Clark AT, Islam S, King Y, Deighton J, Anagnostou K, Ewan PW have a publication entitled Successful oral tolerance induction in severe peanut allergy.

The aim of the study was to investigate whether peanut oral immunotherapy (OIT) can induce clinical tolerance to peanut protein.

Four peanut-allergic children underwent OIT. Preintervention oral challenges were performed to confirm clinical allergy and define the amount of protein required to cause a reaction (dose thresholds).

OIT was then administered as daily doses of peanut flour increasing from 5 to 800 mg of protein with 2-weekly dose increases.

After 6 further weeks of treatment, the oral challenge was repeated to define change in dose threshold and subjects continued daily treatment.

Results: Preintervention challenges confirmed peanut allergy and revealed dose thresholds of 5-50 mg (1/40-1/4 of a whole peanut); one subject had anaphylaxis during challenge and required adrenaline injection. All subjects tolerated immunotherapy updosing to 800 mg protein and i.m. adrenaline was not required. Each subject tolerated at least 10 whole peanuts (approximately 2.38 g protein) in postintervention challenges, an increase in dose threshold of at least 48-, 49-, 55- and 478-fold for the four subjects. Conclusions: We demonstrated a substantial increase in dose threshold after OIT in all subjects, including the subject with proven anaphylaxis. OIT was well tolerated and conferred protection against at least 10 peanuts, more than is likely to be encountered during accidental ingestion. (posted March 7th, 2009)

 

-As reported by Medscape Allergy & Clinical Immunology , at the annual meeting of the AAAA&I held in  Philadelphia, Mar 14-19th, 2008, Dr Scott Nash, MD, allergy fellow-in-training at Duke University Medical Center in Durham, North Carolina, and colleagues, presented their results with Oral Immunotherapy for peanut allergy.

Dr. Nash and colleagues enrolled 20 children between the ages of 1 and 16 years with a history of peanut allergies and measured peanut-specific immunoglobulin E (IgE) antibodies at baseline. The children began ingesting daily doses of peanut flour mixed with food, building up to 300 mg peanut protein, or approximately the amount contained in 1 peanut, ingested daily for 4 to 11 months. Nineteen of the 20 children were able to tolerate the run-in phase of oral immunotherapy. After the run-in phase, patients underwent a food challenge, ingesting 3900 mg peanut protein, or approximately the equivalent of 13 peanuts and 13 times their usual oral immunotherapy dose. Only 1 child had a severe reaction, developing stridor about 90 minutes after the challenge. A few patients had minor reactions, including some urticaria, on food challenge.

Dr. Nash's team is continuing the study, introducing larger doses of peanut protein immunotherapy. "We would like to increase immunotherapy enough to drive IgE down, so that they do not have to take a dose every day, and so that they can be exposed to peanuts safely, just like anyone else eating peanuts," Dr. Nash told Medscape Allergy & Clinical Immunology. (posted March 19th, 2008)

-Dr. Wesley Burks, a food allergy expert at Duke University Medical Center in Durham, N.C., wrote in the Lancet medical journal that a solution appears to be on the horizon:

"I think there's some type of immunotherapy that will be available in five years. And the reason I say that is that there are multiple types of studies that are ongoing now," Burks said in a telephone interview. Ideally, such a therapy would change a person's immune response to peanuts from an allergic one to a nonallergic one, Burks said. (posted May 4th, 2008)

-At the AAAA&I annual meeting held in Washington, DC, March 13-17th, 2009. Jones S.M. et al from the Duke University Medical Center, presented Double-blind, placebo-controlled (DBPC) Trial of Oral Immunotherapy (OIT) in Peanut Allergic Children. The study is a follow-up to the one reported by Nash in 2008 (see posting above): the study phases include: initial day escalation to 6 mg, build-up, and maintenance (4g) dosing followed by a 5g oral food challenge of peanut flour.

Ten subjects, children 1-16 yrs of age, 5 placebo, 5 peanut, completed three phases of the study and oral food challenge (OFC). All subjects reached the maximum dose of 6 mg during the initial day escalation and 4 g during build-up. During OFC, the placebo OIT subjects tolerated a median cumulative dose of 460 mg or approx. one peanut, while all peanut OIT subjects tolerated the maximum of 5000 mg or approx. 13 peanuts.

Conclusion: In this study, early results indicate effective desensitization to ingestion of peanut...Long-term tolerance will be assessed with further enrollment and longer treatment duration of this study cohort. (posted March 20th, 2009)


-As reported by Neil Osterweil, in Medscape Allergy and Immunoloby, March 19, 2009, as a follow-up to the above posted presentation: In other words, parents of peanut-allergic children should be cautioned, "Don't try this at home," said Wesley Burks, MD, professor and chief of pediatric allergy and immunology at Duke University Medical Center in Durham, North Carolina. US Food and Drug Administration approval of oral immunotherapy is likely to be at least a decade away, Dr. Burks added here at the 2009 annual meeting of the American Academy of Allergy, Asthma and Immunology. (posted March 25, 2009)

 

- In J Allergy Clin Immunol. 2009 Jul 2, Jones SM, Burks AW et al have a publicaion entitled Clinical efficacy and immune regulation with peanut oral immunotherapy....Of 29 subjects who completed the protocol, 27 ingested 3.9 g peanut protein during food challenge. Most symptoms noted during OIT resolved spontaneously or with antihistamines...CONCLUSION: Oral immunotherapy induces clinical desensitization to peanut, with significant longer-term humoral and cellular changes. (posted July 12th, 2009)

-Adverse reactions during peanut oral immunotherapy home dosing is an article by Varshney P, Steele PH, Vickery BP, Bird JA, Thyagarajan A, Scurlock AM, Perry TT, Jones SM, Burks AW, that appeared at the beginning of Dec. 2009 in PubMed. It was supposed to be published in the nov issue of the J Allergy Clin Immunol. 2009 Nov 11 which it wasn't for some reason.

The article appeared in the Dec. 10th, 2009 issue of the journal,in the Letters to the editor section. The authors state "We have noted 5 patterns associated with a propensity for reactions to a previously tolerated dose of peanut OIT (oral immunotherapy), including several not previously described. It is interesting that these factors would provoke symptoms after a given OIT dose when, in many of the examples noted, the dose had been tolerated for weeks to months without symptoms: (1) concurrent illness, (2) suboptimally controlled asthma, (3) timing of dose administration after food ingestion, (4) physical exertion after dosing, and (5) dosing during menses. Addressing these factors... has improved the safety profile of our peanut OIT protocol... We expand on reports from other research centers which have described triggers such as infection, exercise, pollen allergy, and irregular intake, and this is the first report involving protocols for peanut allergy.

We have observed that dosing during febrile illnesses has been associated with systemic reactions to previously tolerated peanut OIT doses. We recommend withholding OIT during acute illnesses and advise subjects to resume dosing at home if fewer than 3 doses are missed. If 3 to 5 doses are missed, subjects return to the research unit for observed dosing. Those who miss more than 5 days of dosing might require significant dose reduction or repeat desensitization. In our open-label study2 asthma was associated with a higher rate of chest symptoms during OIT. Of the subjects reporting chest symptoms during home dosing, 82% had coexisting asthma. Several subjects receiving peanut OIT noted cough and wheezing after doses. Some also had chronic cough or exercise-induced respiratory symptoms. Although we did not observe changes in pulmonary function in these subjects, their symptoms improved with the initiation of asthma controller medications... highlighting the importance of diagnosing and treating comorbid atopic conditions. It has not been uncommon for a subject taking a daily OIT dose without eating a meal or snack in the 2 hours before dosing to have symptoms with a dose that had been previously tolerated; taking the same dose with a substantial meal or snack the next day and thereafter prevents further reactions. Additionally, several subjects have experienced allergic symptoms with exercise after OIT dosing, and we advise these subjects to avoid exertion for 2 hours after dosing. Finally, 1 subject had several systemic reactions when menses was coupled with exercise despite no symptoms with daily dosing in the interval between episodes and was eventually withdrawn from the study. She was not taking other medications (eg, nonsteroidal anti-inflammatory drugs). Of note, she did not have systemic reactions each time she exercised during menses. At this time, the role of menses is unclear, and further study is needed.(posted Dec 11th, 2009)

- Reported on CNN Health, Feb. 19th, 2010: "Exciting" advance reported in peanut allergy therapy. Presented at the American Association for the Advancement of Science, in San Diego by Dr Andrew Clark of Cambridge University Hospitals. (posted Feb. 19th, 2010)

 

-In the July, 2010 of the Journal of Allergy and Clinical Immunology, Ananth Thyagarajan, MD, Pooja Varshney, MD, Stacie M. Jones, MD, Scott Sicherer, MD, Robert Wood, MD, Brian P. Vickery, MD, Hugh Sampson, MD, A. Wesley Burks, MD have an article entititled, Peanut oral immunotherapy is not ready for clinical use. Here, available on line, is the article outline  (also at Allergy - Isle of Man) :

Hippocrates wrote that “The physician must… have two special objects in view with regard to disease, namely, to do good or to do no harm” (Hippocratic Corpus, Epidemics, Bk I, Sect 5). As physicians, we are continually challenged with the task of weighing the possible risks and benefits of treatment against those of taking no action. Similarly, we pursue clinical investigation when existing evidence is in a state of equipoise, or uncertainty regarding the comparative therapeutic merits of a particular treatment.1 Only once we demonstrate that action (eg, experimental treatment) is superior to nonaction (or the current standard of care) can we then recommend it with confidence that our practices uphold the principle of primum non nocere—“first, do no harm.”

In the United States, 3.9% of children are affected by food allergy, with an increase in prevalence of 18% from 1997 to 2007.2 Peanut allergy, in particular, affects over 1% of the general population in Westernized countries.3, 4, 5 The current standard of care includes appropriate diagnosis, avoidance of the food, and education of the patient and family. Because treatment options are limited, there is a vital need for new therapeutic modalities. Several groups have studied potential therapies for peanut allergy, including various forms of antigen-specific and nonspecific treatments.6 Peanut oral immunotherapy (OIT) in an open-label study has been shown to raise the threshold dose of reaction to ingested allergen, resulting in clinical desensitization for the majority of subjects.7 Peanut OIT is also associated with decreased peanut skin prick test size, antigen-specific basophil activation, and allergen-specific IgE as well as increased allergen-specific IgG4, regulatory T-cell number, and associated cytokine levels while on therapy. Nevertheless, numerous unanswered questions surrounding this investigational treatment remain, with the foremost being the risks of OIT compared with food avoidance (ie, incidence of accidental ingestion). Additional unanswered questions include issues associated with dosing regimens, patient selection, postdesensitization strategy, allocation of clinical resources, and reimbursement.

With current forms of OIT, as with other forms of immunotherapy, up to 18% of patients undergoing treatment will not be able to endure the associated side effects.7, 8, 9, 10, 11, 12 In addition, accidental ingestions do pose a threat, with events occurring in about 15% of children with peanut and tree nut allergy over a 4-year period.13, 14 The major issue to address is whether the likelihood of patients experiencing accidental food reactions over a given period is more or less than the percentage of patients who cannot tolerate OIT.

In initial studies, peanut OIT has been generally safe but not without risk. In an earlier open-label peanut OIT protocol, the risks of reaction during the initial escalation day, build-up phase, and home dosing were 93%, 46%, and 3.5%, respectively.15 In a more recent study of open-label peanut OIT during the 1-week rush immunotherapy phase, 17 of 22 subjects could not reach the 500-mg dose of peanuts.12 In fact, 18% of subjects in this protocol dropped out secondary to side effects from peanut OIT. Unlike subcutaneous immunotherapy for inhalant allergens, OIT is administered daily, with the majority of OIT doses given at home. Despite the infrequent incidence of allergic reactions with home dosing (<4% of doses), certain factors may be associated with an increased likelihood of reacting with a home dose, including (1) dosing during concurrent illness, (2) suboptimally controlled asthma, (3) timing of dose administration after food ingestion, (4) physical exertion after dosing, and (5) dosing during menses.16 Because OIT continues to be studied in research settings, other patterns may emerge, providing important information to characterize its safety profile further.

It is also important to recognize that OIT to other foods has been associated with adverse reaction rates equal to or even exceeding those seen with peanut OIT. In fact, in a double-blind study of milk OIT, reactions were seen in nearly half of all doses, with over 10% requiring treatment.8 Further, other less common but potentially more important adverse consequences of OIT, such as eosinophilic esophagitis, clearly deserve further study.11

Oral immunotherapy protocols currently under investigation use different dosing schedules and varying durations of treatment. The selection criterion for these protocols excludes individuals with a history of anaphylaxis with hypotension, which may represent many patients seeking this treatment in the clinical setting. Specific patient selection characteristics need further refinement because it has not yet been shown who may benefit most from the protection conferred by OIT treatment. “Desensitization” in this context refers to increasing the threshold of food needed to cause an allergic reaction, while on ongoing therapy, whereas “tolerance” is defined as resolution of allergy without ongoing treatment.17 Individual patients and their families may have differing goals of therapy with respect to desensitization versus tolerance. The protective effects that are seen while still on therapy include a significant change in the family's perception of their quality of life,18 but we do not know what happens once therapy has been discontinued. Current protocols are investigating whether treatment with higher OIT doses leads to an increased chance of inducing tolerance, but this strategy may come with increased risk. These factors must be elucidated in the research setting before widespread use.

Additional work is needed in designing a postdesensitization strategy for patients who demonstrate effective desensitization with OIT treatment. How much peanut should desensitized subjects ingest to maintain their state of protection? How often? Although there is evidence of increasing the threshold dose,7, 19 the ability to incorporate peanut freely into the diet is still in question. Without further investigation, clinicians will be unable to provide advice on the basis of objective data. In addition, this treatment may create a false sense of security leading to lax behavior in terms of access to self-injectable epinephrine and/or inappropriate emergency facility treatment with ingestion.

On a pragmatic note, current OIT protocols are time- intensive and labor-intensive, with dedicated study personnel available for observation of subjects postdosing, preparation and administration of doses, monitoring, and ongoing communication with patients and families. Space for initial desensitization, observed dose escalation visits, and challenges is also a concern. Because third-party reimbursement for such services has not yet been established, such personnel and spatial requirements may be difficult to implement. Assessing compliance is imperative given the potential for reactions if doses are missed.20 Modification of checkpoints used in the research setting (pharmacy dose pack inspections, home diaries, and so forth) may need to be carried out.

Oral immunotherapy represents a promising therapeutic intervention for food allergy, but we remain at a state of equipoise with many unanswered questions to be studied, including the risks of OIT compared with avoidance, dosing regimen issues, patient selection, postdesensitization strategy, allocation of clinical resources, and reimbursement. Studies of OIT using other food allergens (eg, milk, egg) are associated with similar side effects and issues as those surrounding peanut OIT.8, 9 Therefore, OIT to neither peanut nor other foods is ready for clinical use.

Although everyone involved in patient care and in novel therapeutic research would like a treatment option to offer individuals with food allergy, now is not the right time. Further studies are needed to address these outstanding issues to determine whether this type of therapy is appropriate for clinical use. (posted Aug. 18th, 2010)

-In the Clin Exp Allergy. 2011 Mar 18: Efficacy and safety of high-dose peanut oral immunotherapy with factors predicting outcome.
Anagnostou K, Clark A, King Y, Islam S, Deighton J, Ewan P. Clinical Relevance: The authors used a novel protocol using gradual updosing, and higher maintenance dose resulting in a better outcome compared with rush protocols. There was a 1000-fold increase in the amount of peanut tolerated with a good safety profile. No serious adverse events occurred. Most subjects tolerated five peanuts and all were protected against amounts likely during accidental ingestion. (posted April, 17th, 2011)

 

-In the J Allergy Clin Immunol. 2011 Mar;127(3):640-6.e1. Kim EH, Bird JA, Kulis M, Laubach S, Pons L, Shreffler W, Steele P, Kamilaris J, Vickery B, Burks AW. have an article entitiled Sublingual immunotherapy for peanut allergy: clinical and immunologic evidence of desensitization. Eighteen children aged 1 to 11 years completed 12 months of dosing and the food challenge...In this double-blind, placebo-controlled study subjects underwent 6 months of dose escalation and 6 months of maintenance dosing followed by a double-blind, placebo-controlled food challenge.

RESULTS:
Dosing side effects were primarily oropharyngeal and uncommonly required treatment. During the double-blind, placebo-controlled food challenge, the treatment group safely ingested 20 times more peanut protein than the placebo group...

CONCLUSION:
Peanut sublingual immunotherapy (SLIT) is able to safely induce clinical desensitization in children with peanut allergy, with evidence of immunologic changes suggesting a significant change in the allergic response. Further study is required to determine whether continued peanut SLIT is able to induce long-term immune tolerance. (posted May 3d, 2011)


-In Prim Care Respir J. 2011 Sep 21. Sheikh A, Nurmatov U, Venderbosch I, Bischoff E. have a publication entitled Oral immunotherapy for the treatment of peanut allergy: systematic review of six case series studies. Free full text

Allergy to peanuts is associated with considerable morbidity and, in a minority of cases, mortality. Natural resolution to peanut  allergy occurs in only a few cases, hence the need to find effective interventions. Peanut oral immunotherapy (OIT) is a potentially important new therapeutic development. Fourteen databases were searched for published reports and unpublished/in-progress studies. We included studies employing randomised controlled trial (RCT), quasi-RCT, controlled clinical trial, controlled before-and-after, interrupted time series, and case series designs.

RESULTS:
Six studies enrolling a total of 85 participants satisfied our inclusion criteria. All studies employed a case series design and were thus judged to be at high risk of bias. Overall, this body of evidence provided suggestive evidence that it is possible for many participants to increase their threshold dose for peanut exposure whilst receiving treatment. Adverse reactions were common and, whilst most of these were relatively minor, some were potentially life-threatening.

CONCLUSIONS:
OIT appears to be a potentially promising new therapy for the short- to medium-term management of carefully selected and monitored patients with peanut allergy. The effectiveness and cost-effectiveness of OIT - particularly over the longer term - need to be clearly established using more robust designs before its clinical use can be contemplated. Given the risk of triggering serious adverse reactions, OIT should not be administered outside clinical trial settings. (posted Sept. 26th, 2011)

 

Living with peanut allergy

-Bullies use peanut butter to threaten kids with allergies. Parents of kids with severe allergies say their kids are increasingly facing threats of being touched or, worse, forced to eat the food they have spent their lives avoiding. (posted May 4th, 2008)

 

re peanut allergy and commercial airlines

-In Ann Allergy Asthma Immunol. 2008 Jul;101(1):51-6, Comstock SS et al have a publication entitled Allergic reactions to peanuts, tree nuts, and seeds aboard commercial airliners. Telephone questionnaires were administered to individuals in a peanut, tree nut, and seed allergy database who self-reported reactions aboard aircraft. Airlines were contacted to obtain information on food allergy policies.

RESULTS: Forty-one of 471 individuals reported allergic reactions to food while on airplanes, including 4 reporting more than 1 reaction. Peanuts accounted for most of the reactions. Twenty-one individuals (51%) treated their reactions during flight. Only 12 individuals (29%) reported the reaction to a flight attendant. Six individuals went to an emergency department after landing, including 1 after a flight diversion. Airline personnel were notified of only 3 of these severe reactions. Comparison of information given to 3 different investigators by airline customer service representatives showed that inconsistencies regarding important information occurred, such as whether the airline regularly serves peanuts.

CONCLUSIONS: In this group of mainly adults with severe nut/seed allergy, approximately 9% reported experiencing an allergic reaction to food while on board an airplane. Some reactions were serious and potentially life-threatening. Individuals commonly did not inform airline personnel about their experiences. In addition, the quality of information about flying with food allergies available from customer service departments is highly variable and, in some cases, incomplete or inaccurate. (posted Aug. 12th, 2008)

-In the section 'Letters to the Editor' of the J Allergy Clin Immunol. 2009 Sep;124(3):598-9, Greenhawt MJ, McMorris MS and Furlong TJ wrote: Self-reported allergic reactions to peanut and tree nuts on commercial airlines.

A survey was done in conjunction with the Food Allergy & Anaphylaxis Network from mid-Aug. 2007 to early March 2008. Two hundred and eighty five persons responded with 150 meeting the criteria for inclusion by affirming they had an in-flight reaction to peanut or tree nut.

 

Fifty persons (33.3%) reported symptoms that satisfied criteria for anaphylaxis. No fatalities were reported.

Causal allergens included: peanut 64.1%, tree nut 16.9%, both peanut and tree 4.7%, 14.3% were not sure.

The reactions reported: itching 56.5%, hives 47.3%, flushing 37.4%, wheezing 28.8%, throat itching 27.4%, swelling of eyelids/face/lips 24.7%, cough 22.6%, shortness of breath 17.8%, throat tightness/swelling 15.1%, vomiting 7.5%, diarrhea 3.3%, hypotension 1.4%.

Only 10% (15 persons) received epinephrine, and an additional dose was required in 6 of these 15 persons.

77% reported having antihistamine available, which was administered in 71.3% of reactions.

Conclusions: In-flight peanut-allergic reactions continue to be problematic. On-board tree nut reactions are an emerging source of concern compared with a previous study. Individuals continue to fly commercially despite these allergies. Epinephrine is under-administered despite being available on 100% of flights. (posted Nov 11th, 2009)

-Dealing with peanut allergy somewhat exagerated

-As reported on Medscape Allergy & Clinical Immunology, Peanut Allergy Issue Stirs Controversy at Florida

School by Barbara Liston:

 ORLANDO, Fla. (Reuters) Mar 21 - Some public school parents in Edgewater, Florida, want a first-grade girl with life-threatening peanut allergies removed from the classroom and home-schooled, rather than deal with special rules to protect her health, a school official said.

"That was one of the suggestions that kept coming forward from parents, to have her home schooled. But we're required by federal law to provide accommodations. That's just not even an option for us," said Nancy Wait, spokeswoman for the Volusia County School District.

Wait said the 6-year-old's peanut allergy is so severe it is considered a disability under the Americans with Disabilities Act.

To protect the girl, students in her class at Edgewater Elementary School are required to wash their hands before entering the classroom in the morning and after lunch, and rinse out their mouths, Wait said, and a peanut-sniffing dog checked out the school during last week's spring break.

Wait said school leaders will meet this week with parents to address concerns and try to halt inaccurate rumors that children's mouths were being wiped with disinfectant.

Chris Burr, a father of two older students at the school whose wife has protested at the campus, said a lot of small accommodations have added up to frustration for many parents.

"If I had a daughter who had a problem, I would not ask everyone else to change their lives to fit my life," said Burr.

Attempts to teach the girl's parents for comment on Monday were unsuccessful. (posted March 30th, 2011)

 

More on accidental exposure in children with known allergy to peanut

-In Pediatr Allergy Immunol. 2011 Dec 4, Nguyen-Luu NU, Ben-Shoshan M, Alizadehfar R, Joseph L, Harada L, Allen M, St-Pierre Y, Clarke A. published Inadvertent exposures in children with peanut allergy.
ABSTRACT  To determine the annual incidence, characterize the severity and management, and identify predictors of accidental exposure among a cohort of children with peanut allergy, from 2004 to 2009, parents of Canadian children with a physician-confirmed peanut allergy completed entry and follow-up questionnaires about accidental exposures over preceding year.

Results: When all children were included, regardless of length of observation, 266 accidental exposures occurred.... yielding an annual incidence rate of 12.5%.

Conclusion: The annual incidence rate of accidental exposure for children with peanut allergy is 12.5%. Children with a recent diagnosis and adolescents are at higher risk. Hence, education of allergic children and their families is crucial immediately after diagnosis and during adolescence. As many reactions were treated inappropriately, healthcare professionals require better education on anaphylaxis management. (posted Dec. 29th, 2011)

 


More on the impact of peanut allergy on quality of life

-King RM, Knibb RC, Hourihane JO have an article published in Allergy. 2008 Dec 4 entitled  Impact of peanut allergy on quality of life, stress and anxiety in the family.

Forty-six families, who had a child with PA (peanut allergy) completed questionnaires on anxiety and perceived strress. PA children completed a PA specific QoL(quality of life) questionnaire. Parents and sibling also completed QoL proxy questionnaires for the PA child.

Results: Mothers rated their own psychological and physical QoL significantly worse than fathers rated theirs, and had higher scores than fathers for anxiety and stress. Children with PA had significantly poorer physical health-related QoL, QoL within school and general QoL than their siblings did, and greater separation anxiety. The majority of differences were between girls with PA and female siblings. Mothers felt that there was a greater impact on QoL for their PA child, compared with that reported by siblings, fathers or the PA children themselves .

Conclusions: Mothers report that they have significantly poorer QoL and suffer more anxiety and stress than fathers do; this inter-parental difference may be an important feature of family stress caused by PA. Siblings have a similar view of how QoL affects the PA child as the PA child does, while mothers may possibly overestimate this impact. (posted Jan. 11th, 2009)

-At the annual AAAA&I meeting held in Washington DC, March 13-17th, 2009, Hourihane JO et al presented Food Challenge has a Rapidly Established and Persistent Positive Effect on Quality of Life of  Children 0-12 years Irrespective of the Clinical Outcome of the Challenge.

Food challenges are critical to the management of food allergy. Some subjects are reluctant to undergo food challenges, fearing another allergic reaction, and are prepared to remain uncertain about their clinical status. The aim of the authors was to examine the impact of food challenge on health-related quality of life (HRQL) of children 0-12 years, at 2 and 6 month intervals.

Conclusions: Undergoing a food challenge has a significant positive impact on HRQL, irrespective of whether the challenge was positive or negative. This effect is rapidly established, being evident at 2 months, and persistant to at least 6 months post challenge. (posted March 25th, 2009)

 

Peanut and shellfish allergies are markers for asthma morbidity

-This is the title of a presentation at the annual AAAA&I meeting held in Washington, DC, March 2009 by A.B. Simpson et al. In their study of the effect peanut and shellfish allergy had on courses of systemic steroids and need for hospitalisation beyond the age of thee, the authors reviewed the records of 160 children ages 5 to 19 years with the diagnosis of asthma and family history of allergy. 74 had coexistant food allergy; 46 had peanut allergy and 16 shellfish allergy.

Results: Children with peanut allergy were 8.5 times more likely to use more systemic steroids and were 2.4 times more likely to be hospitalized. Children with shellfish allergy were 8.8 times more likely to have greater than 4 courses of oral steroids and were 7.8 times more likely to be hospitalized.

Conclusions: Peanut and shellfish allergies are associated with increased asthma morbidity beyond the age of three. (posted March 22nd, 2009)

 

More on Peanut allergy and asthma

-At the same AAAA&I meeting in Washington, DC, March 2009, Gaffin JM et al presented Peanut Allergy is Associated with Increased Asthma prevalence in Food Allergic Children. Parental questionnaires were distributed to a cohort of 1233 children with known food allergy...re specific food and environmental allergies and parental report of asthma. Children allergic to peanut had twice the odds of parental report of asthma. Furthermore, pollen allergy and pet allergy were significantly associated with asthma.

Conclusions: There is a high prevalence of asthma in the food allergic pediatric population. In children with reported food allergies, peanut allergy is significantly associated with parental report of asthma, independant of other factors. (posted March 24th, 2009)

-Again, at the same AAAA&I meeting in March, 2009, Jaramillo et al presented High-Level Sensitization to Foods is Associated with Asthma ER Visits and current Asthma in the U.S.: Results from NHANES (National Health and Nutrition Examination Survey): 2006-2006. Evaluating 8,203 participants (1-85 yrs) the authors concluded: Our population-based finding that high-level food sensitization is associated with current asthma and ER visits for asthma raises a nationwide concern that food allergy/food sensitization is an under-recognized trigger or risk factor for asthma. (posted March 25th, 2009)

 

Last updated, Feb. 20th, 2012