Evaluation of DipStreak containing CNA-MacConkey agar: A new bedside urineculture device

Background: Many bedside urine culture devices have been developed with the aim of reliability, simplicity and use in both the physician's office and the clinical laboratory. Objective: To compare a novel bedside urine culture device (Dip-Streak(R) N ovamed Ltd., Israel) comprising a combination of MacConkey and Columbia CNA blood agar with conventional seeding on the same culture media. Methods: A total of 1,000 urine specimens sent to our microbiology laborato ry were simultaneously processed by both methods. Results were evaluated af ter 24 and 48 hours incubation at 37 degrees C. Results: Altogether, 171 (17.1%) and 124 (12.4%) specimens were defined as positive by the conventional method using cutoff values of 10(4) colony-for ming units/ml and 10(5) CFU/ml respectively; 178 specimens (17.8%) were def ined as contaminated. The sensitivity, specificity, positive and negative p redictive values of DipStreak for urinary tract infection were 98.8%, 98.6% , 96% and 99.6% respectively, using a cutoff value of 10(4) CFU/ml, and 99. 3%, 99.2%, 96% acid 99.8% respectively, using cutoff value of 10(5) CFU/ml. Full agreement between both techniques was 95%. Conclusions: The agreement rate between DipStreak and conventional seeding was remarkably high. These results suggest that DipStreak in the agar combi nation tested in this study is a useful and precise tool for diagnosing uri nary tract infections.