Sa1161 The High Prevalence of the Positivity to the Lactulose Methane Breath Test in Constipated Patients With Delayed Colonic Transit

Abstract

Background: Methane (CH4) producing small intestinal bacterial overgrowth (SIBO) is related with constipation, however its relationship with colonic motility is unclear. The aims were to evaluate breath CH4 associated with colonic transit and anorectal pressure in constipated patients. Methods: The study with prospectively collected database involved 51 constipated patients who underwent lactulose CH4 breath test (LMBT), colon marker study, and anorectal manometry. The profile of LMBT in patients were compared to 49 healthy controls. The positivity to LMBT was CH4≥10 ppm in baseline or above baseline within 90 min. The types of constipationwere defined as normal transit and delayed transit constipation according to retention of ≥20% colonic markers. Results: The mean age of the patient was 57.3 years (range: 41 ~ 80 years) and 13 patients (23.8%) were men. There were significant differences in the breath CH4 at the time points of 0, 15, 30, 45, 60, 75, 90, 105, 120, and 135 minute intervals between the delayed transit patients and 1) normal transit patients, or 2) healthy controls, respectively (Fig 1). The positivity to LMBT were higher in delayed transit patients (53.3%, 8/15), than in healthy controls (13.9%, 5/36) or in normal transit patients (53.3%, 8/15), respectively (P < 0.01). The delayed transit was the only independent factor for the positivity to LMBT (OR (95% CI), 142.86 (3.44 9090.9), P < 0.01). The left and total colonic transit time were significantly increased in LMBT-positive patients than in -negative patients (16.4±13.4 vs. 32.5±16.9, P < 0.01, and 48.1±40.2 vs. 82.4±36.7, P < 0.01). The significant correlation was shown between total breath CH4 and time of left colonic transit (γ = 0.39, P < 0.01) (Fig 2), or total colonic transit (γ = 0.33, P = 0.02). However, no significant difference was observed in parameters of anorectal manometry according to LMBT status. Conclusions: SIBO was associated with delayed colonic transit, especially with left colonic transit time, accordingly, which might create a vicious cycle. Further investigation is needed to break the link by therapeutic modality such as antibiotics to target the CH4 producing intestinal bacteria.