Pathologic changes in the small bowel in nine patients with diarrhea associated with a coccidia-like body

To confirm a suspected small-bowel injury in patients with a syndrome of protracted diarrhea associated with a coccidia-like body (CLB).

Investigation of an epidemic including a case-control study.

Outpatient clinic in Kathmandu serving primarily the tourist and expatriate community in Nepal.

Nine patients with diarrhea with at least one stool specimen that was positive for the presence of a CLB and seven noninfected volunteer controls.

Clinical data, microscopic examination of stool, bacteriologic and viral studies on submitted stool specimens, upper gastrointestinal endoscopy including duodenal aspiration and microscopy, small-bowel biopsy with subsequent light and electron microscopy.

Endoscopic evidence of inflammation of the distal duodenum was present in five of nine patients with CLB and in none of the seven controls. All nine patients with CLB were noted to have histologic evidence of small-bowel injury, which included acute and chronic inflammation, surface epithelial disarray, and varying degrees of villous atrophy and crypt hyperplasia. One of the seven controls had similar pathologic findings and developed CLB-related diarrhea 5 days later. The other controls had normal distal duodenal histologic results. The organism was found in two of nine duodenal aspirates but was not present in the preserved biopsy specimens as determined by light or electron microscopy.

The pathologic basis of CLB-associated diarrhea appears to be small-bowel injury whose cause remains to be elucidated.