Systematic review–how do we identify urinary tract infections today?

Abstract

Standard urine culture is still considered a gold standard in the identification of Urinary Tract Infections (UTIs), but is time-consuming and in approximately 20% of patients with UTI symptoms produces false-negative results. Medical and scientific communities are in search of a faster, more accurate, yet affordable method with high clinical utility. As a supplement to standard culture in routine practice Urine Flow Cytometer (UFC) screening method is used, in order to detect negative urine culture samples. This allows for shortening issuing time for sterile urine culture reports and the cost of the analysis itself. In addition, urine dipstick tests and microscopic examinations of urine sediment can also be performed in biochemical laboratories but are usually preceded by urine culture. Nowadays, advanced methods such as proteomics and genomics are used to identify pathogens causing UTIs but are still used mainly for scientific purposes and rarely in clinical practice. From genomic methods PCR, 16S rRNA gene sequencing, and metagenome sequencing are being researched. PCR is great for targeted diagnostics, 16S RNA gene amplification can determine bacterial genera and their abundance, but is not good for in-depth species analysis, while metagenomics is the most comprehensive and unbiased method. The proteomics field also offers several methods for microbial identification, with MS as the leading one. Clinical applications of MS platforms usually imply MALDI-TOF MS analyzers which produce a characteristic spectrum called peptide mass fingerprint or more present for scientific purposes LC-MS/MS-based peptide sequencing.