A 47-year-old man with acute worsening of chronic diarrhea was admitted to the hospital with a serum creatinine of 2.2mg/dL from a baseline of 1.6mg/dL. Medical history was remarkable for type 1 diabetes mellitus (diagnosed 8 years prior) complicated by kidney failure requiring kidney-pancreas transplant (cytomegalovirus [CMV] IgG-positive donor; CMV IgG-negative recipient) 3 years before presentation. The patient reported having long-standing diarrhea with 5 to 8 bowel movements per day for 25 years.