Is a negative dipstick urinalysis good enough to exclude urinary tract infection in paediatric emergency department patients?

Abstract

Background: Urinary tract infection is a common cause of serious bacterial infection in young children. The non‐specific presentation has implications for misdiagnosis and the potential for long‐term complications. Aims: To determine if a negative dipstick urinalysis is adequate to exclude urinary tract infection in children aged 0–10 years. Data was subdivided into two age groups: 0–2 years and 2–10 years. Methods: Retrospective case note review over an 8‐month period. Cases included required a printed urinalysis recorded from the Clinitek 50 (Bayer) machine and a printed microscopy and culture result. We defined a negative urinalysis as being negative for all of blood, protein, leucocytes and nitrites. A total of 375 cases were included for statistical calculation. Results: Three hundred and seventy‐five cases gave a prevalence of 10.7% with a sensitivity of 92.5%, specificity of 39.4% and a negative predictive value of 97.8%. In the 0–2‐year‐old group, we demonstrated a prevalence of 15%, a sensitivity of 87.5%, specificity of 39.7% and a negative predictive value of 94.7%. This compares to the older group (2–10 years) with a prevalence of 7.0%, a sensitivity of 100%, specificity of 39.7% and a negative predictive value of 100%. Conclusions: Prevalence of urinary tract infection varied with age with a higher prevalence in the 0–2 years age group. The lower negative predictive value and the higher clinical importance in this age group means that dipstick urinalysis is inadequate to exclude urinary tract infection. Conversely, we believe that children in the 2–10 years age group can adequately have urinary tract infection excluded with a negative dipstick urinalysis.

Rapid tests and urine sampling techniques for the diagnosis of urinary tract infection (UTI) in children under five years: a systematic review

“…A total of 39 studies reporting 107 data sets evaluated dipstick tests for the diagnosis of UTI [28-66]. These studies assessed the utility of dipstick tests for nitrite, leukocyte esterase (LE), protein, glucose and blood, alone and in combination.…”

Urine dipstick as a screening test for urinary tract infection

“…The higher prevalence of UTI among patients of this age has been reported elsewhere. 10,11,14,15 It has been ascribed to the immaturity of the immune system as well as the frequency of undetected structural abnormalities in the urinary tract. 2 Urine dipstick was excellent in excluding UTI in febrile children (NPV 99.2%) and compares very well with reports from several other studies.…”

“…2 Urine dipstick was excellent in excluding UTI in febrile children (NPV 99.2%) and compares very well with reports from several other studies. 13,15,16 However, there was a high rate of false positives [83/112 (74.1%)] and low PPV (26.1%). The PPV of 26.1% is consistent with the 32.8% in another study.…”

Clinical Policy for Well-Appearing Infants and Children Younger Than 2 Years of Age Presenting to the Emergency Department With Fever

“…A Class III retrospective review of 375 pediatric ED patients aged 0 to 10 years from Australia defined a negative urinalysis result as a urine dipstick negative for all blood, protein, leucocytes, and nitrites, and a positive urine culture result as greater than 10 5 organisms/mm 3 of an isolated organism deemed not to be a contaminant. 30 Urine was obtained by bag or clean catch except for 4 cases in which suprapubic aspirate was conducted. For all patients, the researchers found a prevalence of urinary tract infections of 10.7%, urine dipstick sensitivity of 92.5% (95% CI 84.3% to 100%), and specificity 39.4% (95% CI 34.2% to 44.6%).…”