Prevalence of urinary tract infection in acutely unwell children in general practice: a prospective study with systematic urine sampling

Background Urinary tract infection (UTI) in children may be associated with long-term complications that could be prevented by prompt treatment. Aim To determine the prevalence of UTI in acutely ill children <= 5 years presenting in general practice and to explore patterns of presenting symptoms and urine sampling strategies. Design and setting Prospective observational study with systematic urine sampling, in general practices in Wales, UK. Method In total, 1003 children were recruited from 13 general practices between March 2008 and July 2010. The prevalence of UTI was determined and multivariable analysis performed to determine the probability of UTI. Results Out of 597 (60.0%) children who provided urine samples within 2 days, the prevalence of UTI was 5.9% (95% confidence interval [CI] = 4.3% to 8.0%) overall, 7.3% in those <3 years and 3.2% in 3-5 year olds. Neither a history of fever nor the absence of an alternative source of infection was associated with UTI (P = 0.64; P = 0.69, respectively). The probability of UTI in children aged = 3 years without increased urinary frequency or dysuria was 2%. The probability of UTI was >= 5% in all other groups. Urine sampling based purely on GP suspicion would have missed 80% of UTIs, while a sampling strategy based on current guidelines would have missed 50%. Conclusion Approximately 6% of acutely unwell children presenting to UK general practice met the criteria for a laboratory diagnosis of UTI. This higher than previously recognised prior probability of UTI warrants raised awareness of the condition and suggests clinicians should lower their threshold for urine sampling in young children. The absence of fever or presence of an alternative source of infection, as emphasised in current guidelines, may not rule out UTI in young children with adequate certainty.