Retrograde ileoscopy in chronic nonbloody diarrhea: a prospective, case-control study

Chronic nonbloody diarrhea (CND) is a frequent intestinal disorder, with a relevant economic impact. Besides colonic diseases, alterations of the terminal ileum could be involved in CND pathogenesis. The aim of this study was to assess the role of retrograde ileoscopy with biopsy in CND patients.

Patients complaining of CND and matched control subjects were enrolled in the study. Retrograde ileoscopy with biopsy was attempted in all cases. Endoscopic and histological features of Crohn's disease, nonspecific ileitis, and nodular lymphoid hyperplasia were recorded for each patient. Exclusion criteria were presence of any colonic alterations at either endoscopy or histology as well as failure of ileal intubation.

Overall, 156 patients were recruited. Ileal intubation was successful in 149 (95.5%), but 11 (7%) patients were excluded because colonic diseases were detected at histology. At endoscopy, alterations of the terminal ileum were significantly more frequent in patients than in controls (47/138 vs 15/138; p < 0.0001). Crohn's disease (9/138 vs 0/138; p = 0.007) and nonpecific ileitis (18/138 vs 2/138; p = 0.0009) were significantly more frequent in patients than in controls as well as nodular lymphoid hyperplasia (33/138 vs 16/138; p = 0.008). A final diagnosis of Crohn's disease was achieved on the basis of both endoscopic and histological findings in eight (5.8%) patients.

Retrograde ileoscopy is an useful procedure in CND because of its ability to detect alterations in the terminal ileum. Its inclusion in diagnostic workup should be considered.