EC Microbiology

Urinary tract infections (UTIs) represent one of the most prevalent bacterial infections worldwide, affecting millions of individuals annually. While Gram-negative bacteria, particularly Escherichia coli, have traditionally dominated the etiological landscape of UTIs, there is growing recognition of Gram-positive organisms as significant uropathogens. This comprehensive review examines the role of both Gram-positive cocci and bacilli in UTIs, including Enterococcus species, Staphylococcus saprophyticus, Staphylococcus aureus, Streptococcus agalactiae, Lactobacillus species, and Corynebacterium urealyticum. This review provides a comprehensive overview of their epidemiology, pathogenic mechanisms, clinical manifestations, diagnostic challenges, and the evolving patterns of antimicrobial resistance. The increasing prevalence of these organisms, particularly in healthcare-associated infections, complicated UTIs, and immunocompromised patients, necessitates enhanced clinical awareness and targeted therapeutic approaches. Understanding the unique characteristics and treatment considerations for Gram-positive uropathogens is crucial for optimizing patient outcomes and combating the rising threat of antimicrobial resistance.

 Keywords: Urinary Tract Infection; Gram-Positive Bacteria; Enterococcus; Staphylococcus saprophyticus; Streptococcus agalactiae; Lactobacillus Species; Corynebacterium urealyticum; Antimicrobial Resistance; Biofilm Formation; Catheter-Associated UTI

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