Two cases of transplant-acquired food allergy who developed resensitization after a negative oral food challenge

Abstract

Background Cases of food allergy after hematopoietic stem cell and solid organ transplantation in previously nonallergic transplant recipients were reported as transplant-acquired food allergy (TAFA), but information about its long-term outcome is still limited. A phenomenon where patients reacquire food allergy by resuming daily consumption after a negative oral food challenge has not yet been reported. Case presentation We report two cases of TAFA after liver transplantation and cord blood transplantation. In each case, the threshold of daily consumption to cause allergic symptoms decreased when a negative oral food challenge was obtained. Conclusions Our cases show an importance of gastrointestinal tract as a route of food sensitization because thresholds that caused allergic reactions decreased during their resuming process. We need to be careful with possible resensitization once a negative substantial dose was confirmed.