Efficacy of a selective and differential medium for isolating Corynebacterium urealyticum from urine specimens.

OBJECTIVE: To describe a new selective and differential medium for improving the isolation of Corynebacterium urealyticum from urine. METHODS: A total of 370 urine specimens, 270 from patients with underlying urologic disease and 100 from to a control group without renal pathology, were cultured on standard sheep blood agar medium and on a new selective medium for Corynebacterium urealyticum. RESULTS: The use of this selective medium resulted in a nine-fold increase in the prevalence of bacteriuria caused by C. urealyticum (12.4% versus 1.4%). Furthermore, the frequency of patients with symptomatic bacteriuria detected with the selective medium (3.2%) was higher than with the non-selective medium (1.4%). CONCLUSIONS: We recommend the use of this selective medium for the isolation of C. urealyticum in patients with underlying urologic disease or with chronic urinary symptoms.