Sinha R, et al. – The physicians carried out this investigation to determine whether antibiotic reduces voiding cystourethrogram (VCUG)–associated urinary tract infection (UTI). They approved that antibiotic significantly reduces post–VCUG–acquired UTI especially in children with abnormal ultrasound scans.

Methods

• This study consisted of 120 children (age 2 months–5 years) undergoing VCUG.
• Children were randomised into group A (antibiotic, n=72) or group B (no antibiotic, n=48) in 3:2 ratio.
• Group A received oral antibiotic (cephalexin if <6 months or co–trimoxazole if >6 months old) a day prior to VCUG and continued for 1 day post VCUG.
• The main outcome measure was incidence of VCUG–associated UTI.
• Urine was checked on day 3 after VCUG.
• UTI was defined as significant growth of a single organism in a symptomatic child.

Results

• The median age was 8 months (IQR 13 months) with 68% male.
• Indication for undertaking VCUG was history of UTI (first UTI in infancy=43, recurrent UTI=49) and congenital anomaly of kidney and urinary tract without any UTI (n=28).
• Among group B, post–VCUG UTI was significantly higher compared to group A (17% (n=8) vs 1.4% (n=1); p=0.01, OR=14.2 (95% CI 1.7 to 117)).
• Multivariate binary logistic regression analysis found an abnormal pre–VCUG ultrasound scan to be a significant independent risk factor for post–VCUG UTI (p=0.02, OR=9.51, 95% CI 1.43 to 63.4).
• The number needed to treat with antibiotic to prevent one post–VCUG UTI was 6.5, which reduced to 4 if only the group with abnormal pre–VCUG ultrasound scan was included.