Evaluation of DipStreak containing CNA-MacConkey agar: a new bedside urine culture device

Isr Med Assoc J. 2000 Jul;2(7):563-5.

Abstract

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 (DipStreak, Novamed 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 laboratory were simultaneously processed by both methods. Results were evaluated after 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-forming units/ml and 10(5) CFU/ml respectively; 178 specimens (17.8%) were defined as contaminated. The sensitivity, specificity, positive and negative predictive 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% and 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 combination tested in this study is a useful and precise tool for diagnosing urinary tract infections.

MeSH terms

  • Colony Count, Microbial
  • Culture Media
  • Evaluation Studies as Topic
  • Humans
  • Point-of-Care Systems*
  • Sensitivity and Specificity
  • Urinalysis / instrumentation*
  • Urinalysis / methods
  • Urine / microbiology*

Substances

  • Culture Media