Evaluation of the Vivalytic one Analyser for detecting uropathogenic bacteria and antimicrobial resistances in urine samples of urological patients

Question:

Does the transport of urine samples of urological patients have influence on uropathogen detection rate and antibiotic susceptibility testing of the Vivalytic Urinary Tract Infections (UTI) analyser, a qualitative microarray-based point-of-care (POC) test.

Methods:

During a period of four weeks, we used the Vivalytic test to analyze 126 consecutive urine samples of urological patients (51 women, 75 men) with a mean age of 62,9 years. Samples processed with the Vivalytic UTI test were preselected for bacteriuria by screening with urine flow cytometry (cut-off ≥ 70 cells/µl). To evaluate the transport effect on the uropathogens within the urine samples, we performed the Vivalytic UTI test first at the point-of-care (urological department; before transport) and secondly at the microbiological laboratory (after transport) and compared the results to standard urine culture and antibiotic sensitivity testing according to EUCAST.

Results:

As described in Table 1, the species identification of the nineteen uropathogens reached a diagnostic accuracy of ≥ 90.27% with a negative predictive value (NPV) ≥ 93.67%, except for Staphylococcus epidermidis. Klebsiella aerogenes, Providencia stuartii which were not detected in the tested urine specimens. Staphylococcus saprophyticus was detected solely by Vivalytic UTI before the transport. The results displayed a higher degree of concordance when comparing the standard test with Vivalytic UTI tested after the specimen transport (p = 0.0336). The antibiotic resistance gene detection has a higher diagnostic accuracy after the transport (≥ 84.15) compared to POC-testing (≥ 81.7%), except for Vancomycin resistance genes, that were solely found with the Vivalytic UTI test.

Conclusion:

In this study, the Vivalytic UTI test displayed high sensitivity and specificity in identifying uropathogenic organisms and antibiotic resistance markers directly from clinical urine samples in a point-of-care setting within 146 min. According to our results, the transport had an influence on pathogen detection rate and antibiotic susceptibility testing of the Vivalytic UTI analyser.