Nonviable probiotic lysate of no help in irritable bowel syndrome

Use of a bacterial lysate (BL) containing Escherichia coli and Enterococcus faecalis does not appear to benefit irritable bowel syndrome (IBS) patients across all subtypes, although it shows an efficacy signal in those with diarrhoea-predominant IBS, according to a phase IV study.

The phase IV study randomized 389 patients to receive either BL (n=191) or placebo (n=198) following a 2-week baseline period. Treatment lasted for 26 weeks.

In the cohort, mean duration of IBS symptoms was 116.5 months. Based on the ROME III criteria, 153 patients (39.8 percent) had IBS-D, 139 (36.2 percent) had mixed or alternating bowel habits (IBS-M), 62 (16.1 percent) had constipation-predominant disease (IBS-C), and 30 (7.8 percent) had un-subtyped IBS (IBS-U).

Baseline characteristics and drop-out rates were similar in the BL and placebo groups. Likewise, there were no between-group differences observed in the improvement in global assessment (GAI; 17.4 percent and 14.4 percent, respectively; p=0.4787) and abdominal pain (42.0 percent and 35.4 percent, respectively; p=0.1419). These responses were assessed according to the European Medical Agency IBS guideline.

Posthoc analyses showed that BL had a promising effect on abdominal pain response over time and stool consistency in IBS-D.

The present data demonstrate that the efficacy of probiotics in general may be IBS-subtype specific, with BL showing therapeutic potential in IBS-D. As such, it can be said that different mechanisms factor in both IBS phenotypes and in the action of probiotics.