Infantile urinary tract infection and timing of micturating cystourethrogram

The investigation of infantile febrile urinary tract infection (UTI) is still a subject of debate and controversy. To evaluate for vesicoureteric reflux (VUR) most authorities recommend a micturating cystourethrogram (MCUG) to be performed at least 4 weeks after UTI to avoid false positive.

At a tertiary centre for paediatric specialities, information on 427 infants who had undergone MCUG following a first febrile UTI was prospectively recorded and their case notes reviewed. The infants were divided into two groups: Group A (117) with MCUG performed less than 4 weeks from UTI diagnosis and Group B (310) with MCUG after at least 8 weeks from diagnosis.

Of the 427 children, VUR was detected in 33% of those for whom MCUG was performed less than 4 weeks after UTI diagnosis and in 24% of those for whom it was performed at least 8 weeks after diagnosis.

Neither the prevalence nor the grade of VUR in infants with a first episode of UTI is influenced by the timing of the MCUG following diagnosis. We therefore suggest that it is better to perform an MCUG as soon as possible, provided inflammation has subsided.