Phage Prevalence in the Human Urinary Tract—Current Knowledge and Therapeutic Implications

Abstract

Recent metagenomic analyses imply an immense abundance of phages in the human body. Samples collected from different sites (lungs, skin, oral cavity, intestines, ascitic fluid, and urine) reveal a generally greater number of phage particles than that of eukaryotic viruses. The presence of phages in those tissues and fluids reflects the paths they must overcome in the human body, but may also relate to the health statuses of individuals. Besides shaping bacterial metabolism and community structure, the role of phages circulating in body fluids has not been fully understood yet. The lack of relevant reports is especially visible with regard to the human urobiome. Certainly, phage presence and the role they have to fulfill in the human urinary tract raises questions on potential therapeutic connotations. Urinary tract infections (UTIs) are among the most common bacterial infections in humans and their treatment poses a difficult therapeutic dilemma. Despite effective antibiotic therapy, these infections tend to recur. In this review, we summarized the recent data on phage presence in the human urinary tract and its possible implications for health and disease.

Phage Therapy Related Microbial Succession Associated with Successful Clinical Outcome for a Recurrent Urinary Tract Infection

“…In that case, the patient's improved clinical presentation could be due to biofilm reduction and/or alteration of the urobiome. This hypothesis is congruent with phage disruption of biofilms and dysbiosis-driven UTI [59][60][61]. Such an observation is consistent with our phage selection based on antibiofilm and anti-resistome activity.…”

Bacteriophages as Solid Tumor Theragnostic Agents

“…Yet only a handful of them are well-characterized, leaving a broad scope to discover new ones that could be useful for varied biomedical applications. Phages are also prevalent in the human body and are natural predator to microbiomes seen in skin, oral cavity, lungs, intestines, and the urinary tract [ 41 ]. They play an important role in maintaining bacterial population dynamics in the human body.…”

“…Safe andnon-pathogenic nature: Bacteriophages are usually considered as safe to humans. They co-exist in the human body in large numbers and with their involuntary presence, effectively tackle and kill numerous infectious bacterial pathogens [ 41 ]. Phages are also credited for their antibacterial functions in the human body and with upholding the bacterial population dynamics [ 42 ].…”

The Role of Antibiotic Resistant A. baumannii in the Pathogenesis of Urinary Tract Infection and the Potential of Its Treatment with the Use of Bacteriophage Therapy

“…Bacteriophages can be isolated from various environments [ 22 , 23 , 24 ]. Those specific to A. baumannii are most often isolated from water samples, especially from hospital sewage and almost every part of the human body [ 25 , 26 , 27 , 28 , 29 ]. When examining human samples, bacteriophages were detected in 11% of blood cultures, 14% of cerebrospinal fluid, 23% of urine samples, 28% of serum and 45% of ascitic fluid [ 30 ].…”