Combined endoscopy, aspiration, and biopsy analysis for identifying infectious colitis in patients with ileocecal...

The ileocecal area is commonly involved in infection and inflammatory colonic diseases, but differential diagnosis can be difficult. We identified definitive endoscopic findings and a sample collection method for diagnosing infectious colitis.

In a retrospective study, we analyzed data on 128 patients with ileocecal ulcer who underwent colonoscopy from 2007-2011 at the National Center for Global Health and Medicine in Tokyo, Japan. We collected information on location, size, number, and distinctive endoscopic findings and estimated diagnostic odds ratios (ORs). The sensitivities of microscopy, culture, polymerase chain reaction, and histologic methods in identifying patients with infection were compared with those of standard stool, endoscopic aspirated intestinal fluid, or biopsy analyses.

Of the 128 patients, 100 had infections, and 28 had Crohn's disease, Behçet's disease, or other inflammatory diseases. Predictive endoscopic findings were as follows: for amebiasis of the cecum (OR, 17.8), with exudates (OR, 13.9) and round-shaped ulcer (OR, 5.77); for tuberculosis (TB) with transverse-shaped ulcer (OR, 175), scar (OR, 34.6), linear-shaped ulcer (OR, 23.9), or ≥10 mm (OR, 14.0); for cytomegalovirus with round-shaped ulcer (OR, 4.09); and for Campylobacter with cecal valve lesion (OR, 58.3) or ≥10 mm (OR, 10.4). The sensitivity of endoscopic sample collection was significantly higher than that of standard stool sample collection for the diagnosis of amebiasis, TB, non-TB mycobacteria, and other bacteria (P < .05). The methods that detected infection with the highest levels of sensitivity were biopsy with histology for amebiasis, biopsy with culture for TB, biopsy with polymerase chain reaction for cytomegalovirus, and aspiration of intestinal fluid with culture for Campylobacter.

Combining results from endoscopic analysis with appropriate sample collection and pathogen detection methods enables infectious colitis to be differentiated from other noninfectious colonic diseases.