Use of dipsticks for routine analysis of urine from children with acute abdominal pain.

Urinary tract infections are common in infancy and childhood and may indicate an underlying urological problem requiring treatment. The standard method for the diagnosis of urinary tract infection remains the microscopic examination and quantitative culture of a clean catch specimen of urine, but recently a dipstick has become available that tests for two markers of infection-leucocyte esterase and nitrites. Leucocyte esterase is an enzyme from neutrophils not normally found in urine and is a marker of pyuria. Nitrites are produced in urine by the bacterial breakdown of dietary nitrates. Almost all urinary pathogens reduce nitrates to nitrites except for certain pseudomonads and group B streptococci.' The dipsticks have been tested extensively in adults2 but there are few reports of their use in children. Wiggelinkhuizen et al compared dipstick testing with formal urine analysis of 1137 children and concluded that the dipsticks were a reliable screening technique.' Other groups have also recommended that dipsticks be used instead of urine analysis for rapid screening of children for urinary tract infection since negative results for leucocyte esterase and nitrites indicated the absence of infection.45 The routine use of dipsticks for screening children's urine is not widespread in the United Kingdom, and so we have retested them to determine whether they should be adopted for primary screening. tested 133 urine samples with the dipsticks (Multistix 1 OSG, Bayer, Newbury) in our paediatric surgical department. We did not alter our pre-existing criteria for the selection of patients for urine testing: most were children with acute abdominal pain, whose urine was Comparison of using dipstick to test urine samples for markers (leucocyte esterase and nitrites) with urine analysis. Values are numbers Urine analysis Screening with dipstick Infected Not infected Total Both markers positive 10 0 10 One marker positive 2 14 16 Both markers negative 0 107 107 Total 12 121 133 routinely tested. Their mean age was 8-1 years (range 1 month to 15 years), and 71 (53%) were girls. About 86% of the urine samples were taken mid-stream with the rest from a bag or catheter. A positive result was recorded if more than a trace of leucocyte esterase was detected or if any colour change for nitrites occurred. We detected 12 urinary tract infections based on criteria of >20 white blood cells per ,ul and > 108 organisms per litre of a pure culture. Ten of these were positive for both leucocyte esterase …