Urinary Tract Infections Detection with Molecular Biomarkers

Abstract

Urinary tract infection (UTI) is the most prevalent kind of pathogenic bacteria infection, and the midstream urine culture is regarded as the gold standard in UTI diagnosis. Recently, even with modern media and techniques such as polymerase chain reaction (PCR), urinary cultures still create a considerable workload for hospital laboratories. Other UTI-detecting methods, such as flow cytometry and lateral flow immunoassay, suffer from various drawbacks like long time consumption and low sensitivity. Therefore, looking for reliable biomarkers in UTI is urgently needed. In this review, the current definitions of UTI can be basically divided into two main categories: uncomplicated UTI and complicated UTI. In light of anatomical sites, it can be classified as either lower UTI or upper UTI. We take the classification of UTI as a clue and review the reported extensive literature to classify the existing studied markers into the following three categories: Biomarkers used clinically; Promising biomarkers; and Controversial biomarkers. Particularly, the nucleic acid-associated, metabolomic, and lipidomic biomarkers are highlighted. At the end, we discuss the challenges and prospects of biomarkers in UTI, hoping to further inspire the diagnosis of UTI.

Keywords: biomarkers; diagnosis; pathogens; urinary tract infections.

Figure 1

The pathogenesis and anatomical classification of UTI. UTI is mainly caused by the infection of bacteria or other microbes. Taking the bladder as a dividing line, UTI includes the upper UTI (pyelonephritis and ureteritis) and the lower UTI (cystitis, urethritis, and prostatitis).

Figure 2

Category of promising biomarkers for UTI. The promising biomarkers are divided based on different biochemical compositions, including protein and peptide markers, nucleic acid biomarkers, glycosylated markers, metabolomic markers, and lipidomic markers.