Clinical utility of PCR compared to conventional culture and sensitivity testing for management of complicated urinary tract infections in adults: Part II.Evaluation of diagnostic concordance, discordant results, and antimicrobial selection efficacy

Purpose

Complicated urinary tract infections (cUTIs) are difficult to manage due to their polymicrobial nature and resistance to standard therapies. In current clinical practice, the management of a cUTI often starts with broad-spectrum antimicrobials until culture and sensitivity (C&S) results are available, but these diagnostic delays further hinder treatment efficacy. Polymerase Chain Reaction (PCR) offers a faster alternative. This study evaluates PCR's utility compared to C&S, focusing on agreeability, discordant results, clinical outcomes, and antimicrobial selection efficacy to improve cUTI management.

Materials and Methods

The clinical study was conducted in two parts: the primary study focused on patients with cUTIs, while the sub-study involved healthy individuals without signs or symptoms of urinary tract infection (UTI). All collected samples underwent analysis using both PCR and C&S for comparison. Building on the first part of the study, the research evaluated outcome measures related to discordant analysis.

Results

Overall, our study supports good agreement between PCR and C&S in positive cases (95.32 % at baseline and 88.06 % at end of study (EOS)) but reveals some discordance in negative cases (38.30 % at baseline and 62.91 % at EOS). The negative percent agreement (NPA) in the sub-study on the healthy population was 70.16 %. Further analysis of discordant results revealed that symptomatic patients treated for PCR-positive infections trended toward better clinical outcomes (77.45 % vs. 71.42 %) and higher rates of microbiological eradication (53.92 % vs. 50 %) compared to those treated for C&S-positive infections. Additional analysis on antimicrobial use and microbiological aspects revealed that the PCR group received more oral medication-based treatments, while the C&S group received other forms (intramuscular or bladder irrigation). In cases of discordant results, there were more PCR-positive but culture-negative cases than PCR-negative but culture-positive cases.

Conclusions

Our clinical utility study data suggests that PCR-guided management of cUTIs is overall superior to conventional C&S, offering several advantages. PCR has the potential to enhance patient care by enabling the early adoption of narrower antibiotic therapies, improving clinical outcomes, and ensuring the effective selection of antimicrobials. A PCR-guided management plan could be particularly beneficial in managing patients with cUTIs, addressing infections that are occasionally overlooked with current C&S-guided treatment protocols.