Breath methane positivity is more common and higher in patients with objectively proven delayed transit constipation

OBJECTIVESMethane (CH4)-producing intestinal bacteria might be related to constipation. This study was carried out to evaluate the association between breath CH4, colonic transit, and anorectal pressure in constipated patients. METHODSA database of consecutive 62 constipated patients fulfilling the Rome III with the lactulose CH4 breath test (LMBT), a colon marker study, and anorectal manometry was studied. The profile of LMBT in patients was compared with 49 healthy controls. The positivity to LMBT (LMBT+) was defined as CH4 of at least 10 ppm in baseline or above baseline within 90 min. There were two types of constipationnormal and delayed transit. RESULTSThere were significant differences in the breath CH4 between patients with delayed transit and (a) normal transit from 0 to 135 min or (b) healthy controls from 0 to 180 min. The LMBT+ was higher in delayed transit patients than in healthy controls (58.8 vs.12.2%) or in normal transit patients (vs. 13.3%), respectively (P