Point-of-care Testing in Complicated Urinary Tract Infection: Evaluation of the Vivalytic One Urinary Tract Infection Analyser for Detecting Uropathogenic Bacteria and Antimicrobial Resistance in Urine Samples of Urological Patients in a Point-of-care Setting

Background and objective

Urinary tract infections (UTIs) are some of the most encountered infections in clinical practice, exhibiting increasing antimicrobial resistance. Bacterial species identification and antimicrobial resistance testing at point of care (POCT) could improve adequate initial antibiotic therapy and antimicrobial stewardship. In this work, the Vivalytic UTI test, which represents a qualitative PCR-based microarray test, able to detect specific uropathogenic bacteria and associated antimicrobial resistance genes was evaluated at POCT.

Methods

In September 2023, we used this point-of-care testing (POCT) to analyse 126 consecutive urine samples of patients with complicated UTI. Samples processed with the Vivalytic UTI POCT were preselected for the presence of bacteriuria by screening with urine flow cytometry (cut-off ≥70 bacteria per microlitre). We performed the POCT before and after sample transport, and compared the results to standard urine culture and antibiotic sensitivity tests according to the European Committee on Antimicrobial Susceptibility Testing.

Key findings and limitations

Nineteen different bacterial species were detected. Sixteen species reached a diagnostic accuracy of ≥90.27% with negative predictive values of ≥93.67%. The POCT was able to detect bacterial species under the estimated concentration of 10⁴–5 × 10⁴ CFU/ml. The concordant (Vivalytic vs. culture) antimicrobial resistance gene detection rate reached a higher accuracy after transport (≥84.15%) compared to POC-testing before transport (≥81.71%), except for Vancomycin. Aerococcus urinae, Enterococcus hirae, Hafnia alvei, and Staphylococcus lugdunensis are not part of the POCT test panel; these were detected by urine culture only in 19% of cases.

Conclusions and clinical implications

The Vivalytic UTI POCT displayed high sensitivity and specificity in identifying uropathogenic bacteria and antibiotic resistance markers to be further evaluated in clinical practice. However, it would be helpful to expand the resistance to include information about more commonly used antibiotics like aminopenicillins, cephalosporines and fluoroquinolones.

Patient summary

In this study, we tested 126 consecutive urine samples of urological patients with complicated urinary tract infections (UTIs) by using the Vivalytic UTI point-of-care testing before and after sample transport. We found out that the sample transport to some extent influences the pathogen and resistance detection rate of the Vivalytic UTI assay. Compared to standard-of-care diagnostics, pathogen identification was more accurate before sample transport, while the concordant antimicrobial resistance gene detection rate reached higher accuracy after transport.