Rapid detection of bacteriuria with a simple immunoassay test
Methods: Study urines (N = 966) were obtained as de-identified discarded specimens from the University of Washington Medical Center microbiology laboratory. SLRC’s immunoassay test was performed in accordance with instructions, providing a +/- result in about 15 minutes. Standard urine cultures were performed in parallel and all organisms were identified to the species level.
Results: 79% of urine specimens were from an outpatient setting and 21% were from inpatients. With urine culture used as the gold standard, the SLRC test kit identified as positive 244/270 (sensitivity 90%) of samples with E. coli or species of the genera Klebsiella, Proteus, Citrobacter, Pseudomonas, Serratia, Acinetobacter or Enterobacter at a level of ≥103 CFU/ml. The specificity of the test on samples with <103 CFU/ml of Gram negative uropathogens was 94% (523/555).
Conclusion: A new rapid immunoassay test kit for direct detection of Gram negative bacteriuria in patient urine samples performed at high sensitivity (90%) and specificity (94%) as compared with standard culture of urine samples from both outpatient and inpatient settings. Using this assay in point-of-care diagnosis of UTI has the potential to reduce cost of treatment and overuse of antimicrobials for this common infection.
A. Abbott, None
T. Hooton, None