[Perineal bag versus urethral catheterization of suprapubic aspiration for the diagnosis of urinary tract infections in infants in emergency units].

OBJECTIVE: Our objective was to determine the utility of urine cultures collected by sterile perineal bags as a method of diagnosis of urinary tract infection in infants.

PATIENTS AND METHODS: Forty-two patients, aged 0 to 27 months, were diagnosed with urinary tract infections based on the growth of more than 100,000 colonies/ml in two urine cultures collected by sterile bags. Confirmation of the infection was done by urine cultures obtained by suprapubic aspiration or urethral catheterization. A urinalysis was simultaneously performed.

RESULTS: Urinary tract infection was confirmed in only 6 out of 42 patients. The positive predictive value of the sterile bag was 14%, increasing to 42% combined with an abnormal urinalysis.

CONCLUSIONS: The sterile perineal bag is not an accurate method to collect urine for diagnosis of urinary tract infections in febrile infants or those who need prompt diagnosis and treatment.