Probiotics as a Novel Approach Against Acinetobacter baumannii Urinary Tract Infections: A Mechanistic and Therapeutic Review

Urinary tract infections (UTIs) have become a significant clinical problem, with Acinetobacter baumannii emerging as one of the major pathogens associated with UTIs. The increasing resistance of this organism to antibiotics has made treatment options considerably more difficult. This review examines probiotics as a potential preventive strategy against these infections. Existing literature describing the urinary microbiome remains limited and relies largely on studies of voided urine, which provide little clinical relevance, especially given that the urinary tract is colonized by a diverse microbiome, including lactobacilli, staphylococci, and streptococci, which serve as physical barriers to pathogens. However, multidrug-resistant A. baumannii, a gram-negative aerobic bacterium, has made current therapeutic approaches progressively ineffective. Probiotics are live microorganisms that confer protective effects via various mechanisms, such as competition for adhesion to the urinary tract mucosa and the production of antimicrobial substances. In vitro studies have demonstrated that certain strains of Lactobacillus and Bifidobacterium can also inhibit the growth and colonization of A. baumannii. However, clinical data are limited, and further studies are required to determine optimal doses, routes of administration, and the precise mechanisms involved. Taking all this information into account and bearing in mind the increasing drug resistance in A. baumannii, probiotic supplementation may represent a useful preventive and complementary therapeutic approach. These interacting factors may act synergistically to reduce the functional burden of these difficult-to-treat infections in clinical action.