Presentation Authors: Larry T Sirls*, Frank Burks, Howard Korman, Mohammad Jafri, Royal Oak, MI, Natalie Luke, Colleen Kelly, Michael Opel, David Bannouch, Miguel Penaranda, Irvine, CA, Kirk Wojno, Royal Oak, MI
Introduction: Urine cultures (UC) have difficulty with polymicrobial infections and fastidious organisms. PCR based molecular testing can rapidly detect and accurately quantify bacterial, viral and fungal organisms. The objective of this study was to evaluate whether PCR is non-inferior to traditional urine culture in detecting organisms, and polymicrobial infections in symptomatic patients.
Methods: A retrospective review of 582 patients, minimum age of 60, with lower urinary tract symptoms. Traditional UC and PCR molecular urinary tract infection (UTI) testing were run in parallel. Positive UC included one or two organisms and polymicrobial infection was defined as 3 or more organisms. Clinical data were abstracted from the chart.
Results: 582 patients, mean age 77 (60-95), with clinical UTI had UC between March and July 2018. 347 (60%) were male and 235 (40%) female. Clinical symptoms included dysuria (38%), incontinence (33%), urine cloudy / odor (23%) and pain / discomfort (7%). PCR was positive in 56% and culture positive in 37%, Table. Agreement between PCR and UC for positive UC was 90%, exceeding the non-inferiority threshold (p=0.03). PCR detected 85 polymicrobial infections compared to 13 on UC. The most common organisms by PCR were Actinobaculum schaalii (n=89, 15%), Viridians group strep (n=89, 15%), and Aerococcus urinae (n=81, 14%), urinary pathogens that were rarely isolated in UC (n=0, 0%; n=14, 2% and n=3, 0.5%). The two most common bacterial organisms on UC in men and women were E Coli and enterococcus but on PCR these two were the 3rd and 6th most common in women and the 2nd and 3rd most common in men. Importantly, PCR also detected more E Coli and enterococcus infections in both men and women than UC. Non-bacterial organisms were detected in 126/582 (21.6%), yeast = 10 (1.7%) and virus = 117 (20.1%) with JC virus (n=92, 15.8%) being the 2nd most common organism identified.
Conclusions: PCR based UTI analysis is non-inferior in detecting bacterial infections to UC, detecting around 50% additional positive infections, more polymicrobial infections and viral genome in one fifth of cultures. The accuracy of PCR UTI testing over UC may significantly improve patient care.
Source of Funding: Pathnostics