Effects of rifaximin-resistant Bifidobacterium longum W11 in subjects with symptomatic uncomplicated diverticular disease treated with rifaximin.

Background: In medical practice, the use of rifaximin and a probiotic is quite common in patients with a diagnosis of symptomatic uncomplicated diverticular disease (SUDD), with the latter being administered at the end of the rifaximin cycle. The opportunity of having a probiotic strain (Bifidobacterium longum W11) described as being resistant to rifaximin has prompted us to use it routinely in subjects with SUDD, administering it concomitantly with rifaximin.

Methods: Retrospectively, we have analyzed whether our approach conferred a real clinical advantage to patients. The results seem to confirm the logic of our approach.

Results: Patients treated with rifaximin concomitantly receiving strain W11 demonstrated better clinical outcomes than subjects treated with rifaximin followed by strain W11. Moreover, we have observed that the concomitant use of a rifaximin-resistant probiotic has improved the stool consistency of most patients. Finally, the adherence to the given therapy was very different, being very high in subjects undergoing concomitant use of the W11 strain and rifaximin, and being low in the other group. This is probably because of the different duration of therapy (7 days versus 14 days) and due to the fact that after 7 days of rifaximin treatment, patients felt better and decided not to proceed with the probiotic administration.

Conclusions: Despite the many biases that our retrospective analysis presents, we believe that a probiotic strain demonstrating a strong non-transferable resistance to a particular antibiotic should be used along with that specific antibiotic, at least in cases of SUDD diagnosis.