A review of the literature and our own series revealed 38 patients with lower gastrointestinal (LGI) hemorrhage among 4086 renal transplant recipients (0.9%). These patients represent 30% of 128 patients with major colorectal complications in this group. Of the 32 patients whose treatment and outcome were reported, only 12 (38%) were treated operatively. The overall mortality rate was 72%. The causes of LGI hemorrhage included colitis from opportunistic infections (42%); pseudomembranous, ischemic, or uremic colitis (40%); and idiopathic ulcers of the colon (18%). Colonoscopic, gross, and histopathologic findings of a patient with massive LGI hemorrhage from a fungal ulcer of the colon are the focus of this study, as are the implications of such findings. We propose an algorithm for diagnostic and therapeutic management decisions. We emphasize prompt diagnosis and the importance of colonoscopy. We propose withdrawal of immunosuppression and early operative intervention if the patient survival rate is to improve.