Methane production may be directly related to colonic transit time. To analyze this relationship, Ana Soares, MD, PhD, and colleagues conducted a study (reported in the Journal of Clinical Gastroenterology, July 2005) of 40 children aged 3 to 13 years with chronic constipation. Using radiopaque markers, total and segmental colonic transit times were measured. Soiling (associated with methane production in pediatric patients) occurred in 34 of the 40 patients. Methane was produced in 73.5% (25/34) of patients with constipation and soiling and in only 16.7% (1/6) in those with constipation but no soiling (P = .014).
The median total colonic transit times for each group were 80.5 and 61.0 hours, respectively (P = .04); ≤62 hours was normal. The segmental colonic transit times were 17.5 and 10.5 hours, respectively (P = .580), in the right colon; 29.5 and 10.5 hours (P = .001), respectively, in the left colon; and 31.5 and 27.0 hours (P = .202), respectively, in the rectosigmoid (normal values, 10, 10, and 32 hours, respectively). By the sixth week of treatment (enemas, laxatives, fiber), the number of methane producers decreased by 65.2% (15/23). Total colonic transit time was reduced by 50.2% in non-methane producers, suggesting that the presence of breath methane in children with chronic constipation may be an indication of prolonged colonic transit time.