A New Gold Rush: A Review of Current and Developing Diagnostic Tools for Urinary Tract Infections

Abstract

Urinary tract infections (UTIs) are one of the most common infections in the United States and consequently are responsible for significant healthcare expenditure. The standard urine culture is the current gold standard for diagnosing urinary tract infections, however there are limitations of the test that directly contribute to increased healthcare costs. As a result, new and innovative techniques have been developed to address the inefficiencies of the current standard—it remains to be seen whether these tests should be performed adjunctly to, or perhaps even replace the urine culture. This review aims to analyze the advantages and disadvantages of the newer and emerging diagnostic techniques such as PCR, expanded quantitative urine culture (EQUC), and next generation sequencing (NGS).

Emerging Role of Microbiome in the Prevention of Urinary Tract Infections in Children

“…This approach has changed with the start of the Human Microbiome Project, the first large-scale mapping of the human microbiome using culture-independent methods. Standard urine cultures detect aerobic and fast-growing bacteria, while slow-growing anaerobic microorganisms or bacteria that require different growth conditions remain undetected [ 12 , 13 ].…”

“…Relatively recently, due to advances in bacterial assessment, it has been shown that the bladder is not a sterile environment [ 12 ]. In particular, new diagnostic techniques such as PCR, expanded quantitative urine culture (EQUC), whole-genome sequencing (WGS), and next-generation sequencing (NGS) including 16S ribosomal RNA gene sequencing allowed the discovery of uncultured microorganisms and revealed the existence of a urinary microbiome [ 12 , 13 , 14 ].…”

Applying Diagnostic Stewardship to Proactively Optimize the Management of Urinary Tract Infections

“…With a 95% sensitivity and 85% specificity at growth thresholds as low as 10 2 CFU/mL, the standard urine culture with sensitivity has been the clinician gold standard for diagnosing UTIs [91]. Although a clinically validated diagnostic tool, standard urine culture with sensitivity is not without its limitations.…”

“…Although a clinically validated diagnostic tool, standard urine culture with sensitivity is not without its limitations. The current process takes 48 to 72 h to receive organism identification with associated susceptibility data, allowing for a longer than necessary course of a potentially ineffective or overly broad agent [22,91,92]. Additionally, there has been controversy over the growth threshold to define a clinically significant and positive urine culture.…”

“…Additionally, there has been controversy over the growth threshold to define a clinically significant and positive urine culture. It is debated that the traditional threshold of > 10 5 CFU/mL is too high and will result in a missed UTI diagnosis as 25 to 40% of women with symptoms consistent with a UTI will present with a negative urine culture at this threshold [91,92]. Moreover, while standard urine culture techniques can reliably identify E. coli, they struggle to detect other uropathogens such as Enterococci and Group B streptococci with positive predictive values of 10 and 33%, respectively [92].…”