Monitoring and antibacterial treatment for postoperative bacterial overgrowth in Crohn's disease

PURPOSE: Bacterial overgrowth sometimes complicates the clinical course of Crohn's disease and may lead to inappropriate treatment. To clarify the effect of antibiotic therapy, we monitored the hydrogen concentration in expiratory breath after fasting. METHODS: We evaluated 18 patients (15 males; median age, 32.7; range, 22.3-60 years) for postoperative bacterial overgrowth symptoms and for intestinal dilation by plain abdominal x-ray. Five patients had ileitis and 13 patients had ileocolitis. Various intestinal resections were performed in all, and strictureplasties were done at the same time in 13 patients. The median postoperative period was 10.2 (range, 1.2-102) months. Nine patients, who had symptoms such as bloating, nausea, vomiting, or pain, were classified as the symptomatic group, whereas nine other patients, who had no symptoms, were classified as the symptom-free group. Sixteen patients who bad undergone intestinal resections for noninflammatory bowel disease served as the control group. After overnight fasting, hydrogen concentration in end-expiratory breath was measured with gas chromatography. At the same time clinical examinations of white blood cell count, hemoglobin, total protein, serum albumin, iron, sialic acid, and C-reactive protein in the peripheral blood were performed. To assess the effect of antibacterial treatment, changes in symptoms were assessed in eight patients who received antibacterial treatment. Hydrogen concentration was measured repeatedly before and after treatment in six patients. RESULTS: The symptomatic group had an expiratory hydrogen concentration level significantly higher (median, 40; range, 20-139 ppm) than the control group (median, 3; range, 1-6 ppm) and the symptom-free group (median, 4; range, 1-10 ppm). After the antibiotic treatment the symptoms were improved in all of the patients, and the hydrogen concentration level was significantly reduced (median, 4.5; range, 2-13 ppm). CONCLUSIONS: Antibacterial treatment was useful in the postoperative patients whose assessments were complicated by bacterial overgrowth. Using a hydrogen breath test, bacterial overgrowth was effectively monitored and managed, effecting a change in clinical symptoms.