Gastrointestinal complications in the neutropenic patient: characterization and differentiation with abdominal CT

To characterize the computed tomographic (CT) findings of gastrointestinal complications in neutropenic patients and to identify CT features that can help differentiate these complications.

Abdominal CT scans obtained during a 6-year period were reviewed retrospectively to identify 76 neutropenic patients with radiologic bowel abnormalities. Scans were analyzed for wall thickening, pneumatosis, wall nodularity, mucosal enhancement, bowel dilatation, ascites, and mesenteric stranding. The location and extent of abnormalities were noted. Independent chart and pathology report reviews were used to determine the patients' final diagnoses: neutropenic enterocolitis (n = 53), Clostridium difficile colitis (n = 14), graft-versus-host disease (n = 7), cytomegaloviral colitis (n = 1), and ischemic bowel (n = 1). Results were assessed with the Student t test for quantitative wall thickness and the chi2 test for the number of patients with each diagnosis who demonstrated each CT finding.

Mean bowel wall thickening was greatest in C difficile colitis (12 mm) and least in graft-versus-host disease (5 mm). Pneumatosis was limited to neutropenic enterocolitis (21% [11 of 53 patients]) and bowel ischemia. Wall nodularity was significantly more common (P <.01) in C difficile colitis (36% [five of 14 patients]). In graft-versus-host disease, the rates of mucosal enhancement and bowel dilatation were highest (P <.05) (71% [five of seven patients] and 86% [six of seven patients], respectively). In C difficile colitis, the rates of ascites and mesenteric stranding were highest (57% [eight of 14 patients] and 71% [10 of 14 patients], respectively). Although findings in neutropenic enterocolitis and graft-versus-host disease could involve any bowel segment, C difficile colitis was always limited to the colon.

Several CT findings can help differentiate specific gastrointestinal complications in neutropenic patients.