Introduction The UK National Institute for Health and Clinical Excellence (NICE) introduced guidelines for the diagnosis, treatment and management of urinary tract infection (UTI) in children and adolescents in August 2007.

Aim The primary aim was to determine whether publication of NICE guidelines was associated with a change in the use of diagnostic imaging investigations in patients with a documented first UTI in a tertiary children's hospital. Secondary aims were to describe the epidemiology, microbiology, prescription of prophylactic antibiotics and follow-up for these children, and the incidence of structural renal tract abnormalities, vesicoureteric reflux and renal uptake defects identified.

Methods Retrospective review of the case notes of patients presenting to Princess Margaret Hospital, Perth, Western Australia with a first UTI over a 4-year period (August 2005–2009). Details of demographics, radiological investigations, microbiology and follow-up were obtained. Data for subjects presenting before and after 31 August 2007 were compared.

Results Data from 659 subjects, median age 6 (range 0–186) months were analysed. Compared with the pre-NICE period, there was no change in the proportion of patients undergoing renal USS in the 2 years following publication of the guidelines. There was a decrease in the proportion undergoing MCUG (p<0.0001) and receiving antibiotic prophylaxis (p<0.0001) and an increase in the proportion undergoing DMSA (p<0.001).

Conclusions Practice changed following publication of the NICE guidelines. While the reduction in MCUG requests and prescription of antibiotic prophylaxis is in line with NICE guidelines, the increase in DMSA requests is contrary to the recommendations.