2003 Volume 63 Issue 2 Pages 60-63
Fasting breath hydrogen has been measured to evaluate the intestinal bacterial overgrowth. As hydrogen production increases when a small amount of carbohydrate is supplied to colonic bacteria, the measurement of breath hydrogen concentration has been proposed as an indicator of carbohydrate malabsorption.
Fifty consecutive patients (mean age 63.6 years, M : F＝26 : 24) admitted electively to our hospital for diagnostic nonemergency colonoscopy agreed to participate in this study. All patients were allowed to continue their usual diet until the day before the procedure and were not advised to avoid any liquids. After fasting overnight and collecting a 100 ml of breath sample, at 9 : 00 a.m. patients were told to ingest a 200ml of PEG, containing 12g lactulose, 50ml every 5 minutes for 2 hours. During ingestion of PEG, breath samples were taken at 15-min intervals for 240 min. Breath hydrogen concentration was measured using TGA-2000.
Of 50 patients, 10-13 patients (20-26%) had the breath hydrogen level more than 5 ppm until 45 minutes after ingestion. The increased breath hydrogen level at 15 minutes was found in two patients. There was no difference of fasting breath hydrogen levels between patients with and without small intestinal bacterial overgrowth. No patients with high levels of breath hydrogen complained of dyspeptic symptoms.
