Background: Allogeneic organ transplantation has become a common procedure in acute and chronic organ failure. The major limitation, rejection of the allograft by the host's immune system, can be limited by various immunosuppressive drugs that target the adaptive T-cell response. Most of these drugs are used in the treatment of allergic diseases as well, suggesting that transplant recipients under long-term immunosuppressive therapy should not develop any sensitizations or at least not show any clinical signs of allergy. Surprisingly, organ-transplanted children and adults do report symptoms of type 1 allergies, such as allergic rhinoconjunctivitis, bronchial asthma, and food allergies. Thus far, mainly case reports and series on the occurrence of allergy after orthotopic liver transplantation exist.
Objective: Our purpose with this study was to evaluate in a cross-sectional design the prevalence of immunoglobulin E-mediated sensitizations and type 1 allergies in solid organ-transplanted children and adolescents and to identify risk factors.
Methods: Seventy-eight organ-transplanted subjects (50 kidney, 9 lung, 19 liver; mean age: 14.06 +/- 5.94 years; range 1.42 to 24.25 years) were studied by standardized interviews (modified International Study of Asthma and Allergies in Childhood [ISAAC] criteria), skin-prick tests, and measurement of specific and total serum immunoglobulin E.
Results: Nineteen patients (24.4%) were found to be sensitized to > or = 1 common inhalant or food allergens, as reflected by elevated specific immunoglobulin E levels and/or positive skin-prick test results, and 8 subjects (10.3%) additionally reported a corresponding present history of atopic diseases. No severe anaphylactic reactions were reported. No statistically significant associations with gender, kind of transplanted organ, distinct immunosuppressive therapies, and age at time of transplantation or age at investigation were found (chi2 test, Fisher's exact test, and Wilcoxon rank-sum test, respectively). Multiple logistic-regression analysis did not identify any independent risk factor either.
Conclusion: This study demonstrates that therapeutic immunosuppression does not control sensitizations and clinical manifestation of type 1 allergies in organ-transplanted children and adolescents.