Croup as Unusual Presentation of Post-transplantation Lymphoproliferative Disorder after Liver Transplantation in an 18-month-old Child.

Post-transplantation lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation that occurs due to immunosuppression and other risk factors. PTLD may present with involvement of other organs and with unusual presentation. The presentation is often extranodal (e.g., in the gastrointestinal tract, lung, or the central nervous system). Herein, we report on a 1.5-year-old girl who underwent liver transplantation almost 5 months prior to admission. She was on medications such as tacrolimus and prednisolone. Her presentation was started with symptoms of the upper respiratory infection followed by croupy cough and respiratory distress with no response to usual treatments. She had respiratory arrest during broncoscopy. Therefore, emergency tracheostomy was done. Biopsy from the paratracheal mass revealed large B cell non-Hodgkin lymphoma (PTLD, monomorphic and high grade). This case presentation shows that persistent upper airway symptoms, particularly stridor and croupy cough, in children who underwent liver transplant should be further evaluated; the physician needs to have a high degree of clinical suspicion for the diagnosis of PTLD in this situation.