Diagnosing urinary tract infections in children: research-based rules to aid decision making in primary care

Background: It is well recognised that tThe diagnosis of Urinary Tract Infection’s (UTIs) in young , pre-verbal, children is challenging and may mean some are not actually either suspected or diagnosed. Missed diagnosis can lead to immediateUndiagnosed infections increase suffering and may lead topossible serious long term health problems. Methodology: 7,163 systemically unwell children were recruited in primary care. Urine samples were collected and a wide range of presenting symptoms and signs were recorded to identify which, if any, could predict a urinary tract infection.Findings: Half of laboratory-confirmed UTIs were missed at first contact in primary care. Samples obtained using Newcastle nappy pads were 6 times more likely to be contaminated. The clinical algorithms discussed here improve clinicians’ ability to determine UTI from other causes of constitutional illness.Conclusions:•Urine samples should be collected using the ‘clean catch’ method whenever possible•Presence/absence of fever is not diagnostic for UTI in this age group in primary care•Symptoms and signs can be used to help decide which children to obtain a urine sample from•Dipstick testing of urine improves the targeting of antibiotic treatmentIt is well recognised that the diagnosis of Urinary Tract Infection’s (UTIs) in young, pre-verbal, children is challenging and may mean some are not actually either suspected or diagnosed. Missed diagnosis can lead to immediate suffering and possible serious long term health problems. The DUTY study was undertaken to help clinicians recognise when to consider attempting to collect a urine sample and when to consider treatment. It also found because of the way the project was run a difference in both UTI positivity Symptoms and Signs and the presence of contamination between nappy pad urine collection and clean catch collection. The study recruited in Primary Care and as such the results are not directly comparable to any earlier studies. Children were eligible if presenting with any acute illness of less than 28 days’ duration, where the illness was associated with: (a) at least one constitutional symptom or sign identified by the National Institute of Health and Clinical Excellence (NICE) as a potential marker for UTI, i.e.: fever, vomiting, lethargy/malaise, irritability, poor feeding and failure to thrive; and/or (b) at least one urinary symptom identified by NICE as a potential marker of UTI, ie :abdominal pain, jaundice (children <3 months only), haematuria, offensive urine, cloudy urine, loin pain, frequency, apparent pain on passing urine and changes to continence.In the clean catch group the parent-reported index tests associated with a UTI were: pain/crying while passing urine, smelly urine, previous UTI and, notably, absence of severe cough. For pain/crying while passing urine and smelly urine the higher these index items were scored, the more severe the UTI proved to be. Analysis of the dipstick results showed that leukocytes, nitrites and blood were strongly associated with UTI.In the nappy pad group parent-reported smelly urine, darker urine, female gender and the absence of a nappy rash were independently associated with UTI. As with the clean catch group, there was evidence for graded associations in the first two items. On dipstick testing these urines, the presence of leukocytes and nitrites (but not blood) were independently associated with UTI. Contamination was x6 more likely in this group in comparison to the clean catch group.In conclusion urine samples should be collected using the ‘clean catch’ method whenever possible.Presence/absence of fever is not diagnostic for UTI in this age group in primary care.Symptoms and signs to be considered when deciding whether to collect urine These can be used for deciding which children to urine sample (step 1) and dipstick results to improve specificity for antibiotic treatment (step 2).