Biofilm Disruption Enhances Antimicrobial Therapy for Small Intestinal Bacterial Overgrowth and Intestinal Methanogen Overgrowth.

Background Small intestinal bacterial overgrowth (SIBO) and intestinal methanogen overgrowth (IMO) are forms of microbial dysbiosis linked to gastrointestinal as well as systemic symptoms and sequelae. Some patients prefer non-antibiotic treatment options, and thus, herbal antimicrobials are emerging as alternatives to rifaximin. Treatment with pharmaceuticals or herbals can be hindered via biofilm-related resistance. This retrospective chart review evaluated whether adding a biofilm disruptor to herbal antimicrobials enhanced SIBO/IMO eradication, as defined by standardized breath test criteria.  Methods Thirteen patients with SIBO, IMO, or both, as determined by lactulose breath testing, had previously been randomized in a clinical protocol to receive either herbal antimicrobials alone (n = 5, control group) or herbal antimicrobials combined with biofilm disruptors (n = 8, treatment group) over an 8-week period.  Results Hydrogen levels declined more in the treatment group compared with controls (-30.75 vs -11.40 ppm, within-group P = 0.007). Methane levels also decreased more in the treatment group than in controls (-26.38 vs -2.00 ppm, within-group P = 0.042). The SIBO eradication rate ranged from 60-100%, but did not differ significantly across groups. Neither group achieved eradication of IMO.  Conclusions Adding a biofilm disruptor to herbal antimicrobials was associated with significantly greater reductions in hydrogen and methane gas levels. While SIBO eradication rates with herbal protocols - both with and without biofilm agents - were comparable to those seen with rifaximin, the differences were not statistically significant; importantly, this was likely due to the small sample size. Larger prospective, controlled studies are needed to validate these findings and clarify the potential role of biofilm disruptors in the management of SIBO/IMO.