Evaluation of the Coral UTI Screen system for rapid automated screening of significant bacteriuria in a regional centralized laboratory.

An evaluation of the Coral UTI screen system (Coral Biotechnology, San Diego, CA) compared to urinalysis/urine culture was done to assess its performance for rapidly screening a high volume of urine samples for significant bacteriuria in a regional central microbiology laboratory. A total of 1094 urine samples from ambulatory patients were evaluated. 670 (61.2%) urine samples were negative or positive [178 (16.3%)] by both methods. 217 (19.8%) other samples were UTI screen positive but had either no growth or no uropathogens on culture; 9 of these samples were possibly false negative by culture because of the presence of pyuria, indicating the presence of either a urinary tract infection or another inflammatory process. Another 29 (2.7%) samples had false negative screens because the urine culture was positive, but only 5 of these patients were treated with antibiotics after urine specimen collection. Overall, the Coral UTI screen has a sensitivity of 86.0%, a specificity of 75.5% and a positive and negative predictive value of 45.0% and 95.9% respectively. Routine use of the UTI screen would allow same day reporting of 65% of all urine culture results without having to proceed to culture.