Abstract
Male tract infections (MTIs) are a common clinical condition, often presenting without any signs nor symptoms of disease. As advised by the European Urology Guidelines dealing with this topic, patients are typically treated with antibiotics alone. Nevertheless, in between 40% and 50% of cases, antibiotic therapy is not effective in eradicating the semen infection. Therefore, persistent semen infection is frequently found upon semen culture evaluation following antibiotic therapy. In this study, we aimed to analyze the fecal microbiota of male infertile patients with persistent MTI in order to verify the prevalence of gut dysbiosis in these patients. We therefore enrolled 20 infertile patients with persistent MTIs after a proper cycle of antibiotic treatment. All patients performed the study for gut microbiota analysis after about 30 days after the last dose of antibiotic treatment. Gut microbiota analysis revealed that 50% of patients with persistent MTI presented a reduction in microbial biodiversity. Indeed, a situation of gut dysbiosis was reported in 75% of patients. In details, the Firmicutes-Bacteroidetes ratio was reduced in 70% of such patients, including 40% of patients where a severe reduction was observed due to an elevated abundance of Bacteroidetes (putrefactive dysbiosis). The most frequent enterotype was Prevotella-dominant (43%). We demonstrated for the first time that patients with recurrent MTIs have enterotypes associated with increased gut permeability and systemic inflammation. Further studies are required to analyze the molecular machinery by which gut dysbiosis exerts its role in patients with MTIs, in particular persistent MTIs, and how supplementation with probiotics might impact in terms of restoring eubiosis, in terms of eradicating the infection, and reducing prostate inflammation and eventually in terms of improving semen evaluation in male infertile patients.