Gastroenterology clinical image challenge: A 60-year-old man with C3 tetraplegia was referred to our department for evaluation of abdominal pain and hematochezia. He was diagnosed with adrenal insufficiency five years prior and has been taking low-dose prednisolone (7.5 mg) once a day. One year before presentation, he complained of intermittent loose, mucoid stool and abdominal pain. Sigmoidoscopy revealed multiple small yellowish plaques in the sigmoid colon. However, symptoms improved without any treatment, and he was discharged from the rehabilitation department. He was readmitted for respiratory rehabilitation owing to dyspnea. On hospital day four, he complained of abdominal pain and passing loose stool with foul odor four to five times a day. On hospital day seven, the abdominal pain worsened, and hematochezia occurred.
On physical examination, he was hemodynamically stable and afebrile. The abdomen was soft with mild tenderness on palpation in the periumbilical area without peritoneal signs. Laboratory studies were notable with a hemoglobin level of 10.7 g/dL, total protein of 4.09 g/dL and albumin of 2.21 g/dL. Inflammatory marker (C-reactive protein) was mildly elevated to 1.83 mg/dL. Serology for human immunodeficiency virus was negative. Tumor markers, such as carcinoembryonic antigen, carbohydrate antigenic determinant and α-fetoprotein, were within the normal range. Antineutrophil cytoplasmic antibody was negative, and rheumatic factor was within the normal range. Stool for acid-fast bacillus and Clostridium difficile toxin were negative; no pathogens were cultured, and no parasites were identified.
Sigmoidoscopy revealed diverse, multiple polypoid lesions (3–10 mm) with erythema, edema and friability surrounding the entire lumen on the sigmoid colon (figure). The number and size of the polypoid lesions increased compared with the endoscopic findings obtained one year prior. The lesions easily bled on contact. Multiple biopsies of different sites were taken. An abdominal computed tomography scan showed multiple polyps of <1 cm that were confined to the sigmoid.
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