Kate Johnson
March 6, 2012 (Orlando, Florida) — The reason pediatric liver transplant patients have high rates of new-onset food allergy might be hidden in their indication for transplant, Japanese researchers reported here at the American Academy of Allergy, Asthma and Immunology 2012 Annual Meeting.
Patients who require transplantation for biliary atresia have higher rates of new-onset food allergy than patients with other indications for liver transplantation, said Tetsuo Shoda, MD, from the National Center for Child Health and Development in Tokyo, Japan.
In particular, those with a history of intestinal surgery had a 6-fold increase in new-onset food allergy, compared with those with no history, he explained.
The phenomenon of new-onset food allergy after transplantation is seen predominantly in liver recipients; its prevalence has been estimated to be between 10% and 20%, Dr. Shoda told Medscape Medical News.
Findings from previous studies have suggested that immunosuppressant medications such as tacrolimus increase intestinal permeability and trigger allergy, Dr. Shoda said. But this does not explain why new-onset food allergy is more common in liver recipients than in recipients of other organs.
He and his colleagues retrospectively reviewed the charts of 123 children who underwent living-donor liver transplantation at his institution from November 2005 to May 2010. Median age at the time of transplantation was 8 months.
Children received standard doses of tacrolimus and low-dose steroids for initial immunosuppression.
There was a 90% patient survival rate, and therefore 105 patients for analysis.
The indication for liver transplantation was biliary atresia in 44% of these patients, congenital metabolic disease in 25%, fulminant hepatic failure in 18%, liver cirrhosis in 5%, congenital absence of the portal vein in 3%, congenital hepatic fibrosis in 2%, and hepatic tumor in 1%.
Over a median of 10.5 months, 15 patients developed new-onset food allergy after liver transplantation, for a cumulative incidence of 14.3%. The majority of allergic reactions (86%) were urticaria or angioedema, but 47% were gastrointestinal symptoms.
The most common allergen was egg (53%), and 10 patients reacted to more than 2 food allergens. The median total immunoglobulin E level was 438.5 IU/mL.
There was a significant trend toward higher rates of food allergy in patients with biliary atresia than in those without (P = .012).
In the final analysis, the strongest risk factors for the development of new-onset food allergy were being younger than 12 months at the time of surgery (odds ratio [OR], 11.78; P = .003) and having a history of intestinal surgery (OR, 6.69; P = .009).
"Biliary atresia patients usually have had previous intra-abdominal surgeries, which might increase their risk for food problems, causing easier sensitization; after that, the tacrolimus is added," said Dr. Shoda.
Dr. Shoda has disclosed no relevant financial relationships.
American Academy of Allergy, Asthma and Immunology (AAAAI) 2012 Annual Meeting: Abstract 131. Presented March 3, 2012.
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