Histamine-Producing Intestinal Dysbiosis and Its Role in Lower Urinary Tract Infections and Irritable Bowel Syndrome in Young Women

<b>Background:</b> Lower urinary tract infections (LUTIs) and irritable bowel syndrome (IBS) have been associated with histamine-producing gut dysbiosis, characterized by an overgrowth of histaminogenic bacteria and opportunistic fungi. This study examines the relationship between histaminogenic microbial imbalance, dietary factors, and LUTIs in women with IBS, emphasizing the potential nutritional contributions to microbiota modulation. <b>Methods:</b> A cohort of 188 women was evaluated by analyzing the intestinal microbiota associated with sporadic and recurrent lower urinary tract infections and irritable bowel syndrome, along with a questionnaire on risky eating behaviors. <b>Results:</b> Dysbiosis was associated with an overgrowth of histamine-producing bacteria (<i>Escherichia coli</i>, <i>Enterobacter</i> spp., <i>Clostridium</i> spp.) and <i>Candida albicans</i>, along with a depletion of protective taxa (<i>Lactobacillus</i>, <i>Bifidobacterium</i>). Dysbiosis, characterized by an increase in histamine-producing bacteria (<i>Escherichia coli</i>, <i>Enterobacter</i> spp., <i>Clostridium</i> spp.) and <i>Candida albicans</i>, together with a depletion of protective taxa (<i>Lactobacillus</i>, <i>Bifidobacterium</i>), has been associated with lower urinary tract infections and irritable bowel syndrome. Regarding the increase in histaminogenic flora, significant associations with dietary factors concerned only the frequent consumption of fast food. <b>Conclusions:</b> These findings highlight the role of histamine-driven dysbiosis in sustaining chronic inflammation and susceptibility to LUTIs and IBS, supporting microbiota modulation as a potential preventive and therapeutic strategy.