Abstract

Saraswathi Yashaswini*, Manjusha Yadla

ABSTRACT

Gastrointestinal complications are common after renal transplantation and pose a diagnostic challenge because infective, drug-induced, and rejection-related causes overlap in presentation. We report a 26-year-old female who underwent live-related renal transplantation (mother donor) in February 2023 for hypertensive chronic glomerulonephritis with bilateral small kidneys, following 18 months of maintenance hemodialysis. The post-transplant course was marked by mycophenolate mofetil (MMF)-associated diarrhea, invasive pulmonary aspergillosis requiring liposomal amphotericin B and voriconazole with temporary MMF withdrawal, and recurrent episodes of acute kidney injury associated with diarrheal illness and graft dysfunction. Despite extensive infective work-up (stool, CMV, EBV, and other serologies) remaining largely negative, the patient continued to have persistent loose stools with fluctuating renal function. Colonoscopic biopsy ultimately demonstrated apoptotic crypt abscesses and focal basement membrane thickening without granulomas, viral inclusions, or parasites — histological features consistent with MMF-induced colopathy with an early collagenous colitis pattern. Dose reduction of MMF and tacrolimus, along with supportive care, resulted in clinical improvement and stabilization of graft function. This case highlights the importance of considering MMF-induced colopathy as a distinct entity in the differential diagnosis of persistent post-transplant diarrhea, particularly when infective causes have been reasonably excluded, and underscores the value of histopathological confirmation in guiding immunosuppression adjustment without compromising graft survival.