A man in his 30s, who had undergone retrocolic Billroth II reconstruction for perforated duodenal ulcer, presented with watery diarrhea for 2 years and suspected fatty liver. He was referred to our hospital for management of chronic diarrhea, weight loss, hepatopathy and hypoalbuminemia. Initial upper and lower gastrointestinal endoscopies were negative. Since a small bowel lesion was suspected, peroral single-balloon enteroscopy was performed, which identified feces-like residue near the Billroth II anastomotic site and a connection to the colon separate from the afferent and efferent loops. Transanal single-balloon enteroscopy identified a fistula between the gastrojejunal anastomosis and transverse colon, with the scope reaching the stomach transanally. Barium enema confirmed flow of contrast medium from the transverse colon through the fistula to the anastomotic site, allowing the diagnosis of gastrojejunocolic fistula. Liver biopsy showed relatively severe steatohepatitis (Brunt’s classification: stage 2–3, grade 3). Resection of the anastomotic site and partial transverse colectomy were performed to remove the fistula, followed by Roux-en-Y reconstruction. Postoperatively, watery diarrhea resolved and the stools became normal. Hepatopathy and hypoproteinemia improved. One year later, liver biopsy showed marked improvement of steatosis. This case demonstrated marked improvement of both diarrhea/nutritional status and steatohepatitis after treatment of gastrojejunocolic fistula, suggesting that the fistula caused non-alcoholic steatohepatitis. © 2016, Japanese Society of Gastroenterology.
