Cytomegalovirus colitis in AIDS: CT features.

OBJECTIVE

The purpose of this study was to determine the CT features of cytomegalovirus colitis in patients with AIDS.

MATERIALS AND METHODS

Abdominal CT scans of 24 patients with biopsy-proved cytomegalovirus colitis (colonoscopy, n = 14; sigmoidoscopy, n = 8; surgery, n = 2) were jointly reviewed by two observers. Patients were men 26-68 years old (mean age, 39 years; SD, 9 years) with CD4 counts of 3-129 mm3 (mean, 32 mm3; SD, 34 mm3). The mean interval between CT and biopsy was 6 days (range, 0-20 days; SD, 6 days). Scans were assessed for colonic wall thickening (> or = 4 mm), ulceration, mural edema, pericolonic stranding, ascites, lymphadenopathy, and thickening of the small-bowel wall. Mural involvement was recorded as asymmetric or circumferential. Disease location was recorded as ascending colon, transverse colon, descending colon, rectosigmoid colon, or pancolonic.

RESULTS

Colonic wall thickening of 8 to 33 mm (mean, 15 mm; SD, 6 mm) was seen in 22 patients. One patient had pancolonic involvement. The ascending colon was involved in 13, the transverse colon in five, the descending colon in 10, and the rectosigmoid colon in 16. Circumferential colonic thickening was seen in 17 patients. Deep mural ulceration was seen in 15 patients, mural edema in 15, pericolonic stranding in 23, ascites in 10, lymphadenopathy in four, and small-bowel involvement in 10. Two patients had appendicitis. Three patients had perforations (two rectal, one cecal). One patient had a giant rectal ulcer.

CONCLUSION

Although many of the CT features of cytomegalovirus colitis are nonspecific, the diagnosis should be suggested when CT shows colonic wall thickening, particularly if the thickening is associated with mural ulceration in patients with AIDS and CD4 counts of less than 200 mm3.