This review was submitted by Tom Connell.

Background and methods
Although data are contradictory, malodorous urine has been reported in between 2 to 20% of children with urinary tract infection (UTI). In this two-year prospective study in a tertiary care Canadian ED, Gauthier and colleagues investigated whether parental reporting of malodorous urine was associated with confirmed UTI in children aged 1 to 36 months that presented with fever without focus. Results from a standardised questionnaire from parents of 331 children were included in the analysis.

Summary of main findings
Of 331 children (median age 12 month), 51(15%) had a UTI. The majority of urine specimens (88%) were obtained via catheter. Malodorous urine was reported in 57% of children with UTI and 32% of children without UTI. Children with malodorous urine were more likely to have UTI (OR 2.83 (1.54-5.2)) compared to children without malodorous urine, even after adjustment for sex and the presence of VUR. However the sensitivity and specificity of malodorous urine for UTI was only 57% (42-70) and 68% (62-74) respectively.

Implications for practice
Malodourous urine is more likely in children with confirmed UTI. However, 40% of children with a confirmed UTI do not have malodorous urine and up to one third of children with parental reported malodorous urine do not have a UTI, limiting the ability to rule out or rule in a UTI based on this sign alone. Despite the study limitations, the findings suggest that parental reporting of malodorous urine, albeit not perfect, may be a useful clinical sign to aid clinical decision-making in routine clinical practice.