Early Posttransplant Lymphoproliferative Disorder and Cryptosporidiosis After Liver Transplantation

Posttransplant lymphoproliferative disorder (PTLD) is a rare yet potentially fatal complication following liver transplantation. This condition is usually associated with Epstein–Barr virus (EBV) infection and profound immunosuppression. In this report, a young woman is introduced who had undergone liver transplantation due to autoimmune hepatitis and developed persistent diarrhea 3 months after the transplantation. Simultaneously, Cryptosporidium infection was diagnosed as the cause of the diarrhea. However, due to the persistence of symptoms and lack of full recovery with initial treatment, further diagnostic evaluations were conducted. Tissue biopsy confirmed the presence of diffuse large B‐cell lymphoma (DLBCL) as an early‐onset PTLD. Following the diagnosis of PTLD, a reduction in the intensity of immunosuppression and initiation of specific treatment, including the administration of rituximab, were undertaken. Nevertheless, despite the therapeutic interventions, the patient died due to disease progression. This case underscores the necessity of considering PTLD as a differential diagnosis in liver transplant patients presenting with unusual symptoms such as persistent diarrhea—even in the presence of a concurrent opportunistic infection like Cryptosporidium . Timely diagnosis and treatment of PTLD are crucial to improving the prognosis of these patients.