Dipstick urinalysis shows high specificity but low sensitivity for UTI in febrile infants under 12 months

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Frontiers in Medicine Published April 14, 2026 Medically reviewed April 25, 2026 DOI ↗ By Dr. Sofia Müller, MD · Lifespan & Whole-Person Care

Key Takeaway

Interpret negative dipstick results cautiously in febrile infants under 12 months with suspected UTI.

This retrospective cohort study, conducted at a single emergency department, evaluated the diagnostic performance of dipstick urinalysis for detecting pyelonephritis in febrile infants aged 0–12 months presenting without a clear focus of infection. The study compared dipstick results (leucocyte esterase and nitrites) against urine culture as the reference standard. The sample size was not reported.

For leucocyte esterase, specificity was 94% in infants aged 0–3 months and 91% in those aged 4–12 months. Sensitivity was lower at 60% in the 0–3 month group and 71% in the 4–12 month group. For nitrites, specificity was very high (99% in 0–3 months; 98% in 4–12 months), but sensitivity was consistently low at 25% in both age groups. Positive predictive values for leucocyte esterase were 87% and 82% for the younger and older groups, respectively, while for nitrites they were 96% and 87%. Combining the two markers showed no improvement in overall performance.

Safety and tolerability data were not reported. Key limitations include the retrospective design and single-center setting, which may limit generalizability. The study did not report sample size, confidence intervals, or absolute numbers for calculations. Funding and conflicts of interest were also not reported.

For practice, this evidence suggests dipstick urinalysis has high specificity but poor sensitivity for detecting pyelonephritis in febrile infants under 12 months. A negative dipstick result does not reliably rule out infection, particularly given the low sensitivity of nitrites. These findings support current guidelines that emphasize urine culture for definitive diagnosis in this high-risk pediatric population.

Study Details

Study typeCohort

EvidenceLevel 3

PublishedMar 2026

View Original Abstract ↓

Background and objectivesUrinary tract infections (UTIs) are the most common serious bacterial infections during the first year of life. Symptoms of UTI in young children are non-specific, making diagnosis challenging.MethodWe conducted a retrospective single-center study over a period of 5 years. Urine samples collected by suprapubic aspiration, clean catch, or bladder catheterization in children aged 0–12 months presenting to the emergency department with fever without focus and suspected UTI during this period were reviewed from the laboratory archives. We divided our population into two groups of 0–3 and 4–12 months. Data on dipstick urinalysis were collected, with urine culture as the reference standard. Statistical analysis—including sensitivity, specificity, diagnostic odds ratio, likelihood ratio, positive predictive value (PPV), and negative predictive value—was performed for the following dipstick urinalysis parameters: leucocyte esterase alone, nitrites alone, leucocyte esterase and nitrites, leucocyte esterase and/or nitrites.ResultsStatistical analysis showed that in the 0–3-month group, specificity was 94% for leucocyte esterase (LE) and 99% for nitrites (Nit). Sensitivity was 60% for LE and 25% for nitrites. PPV was 87% for LE and 96% for nitrites. In the 4–12-month group, specificity was 91% for LE and 98% for nitrites. Sensitivity was 71% for LE and 25% for nitrites. PPV was 82% for LE and 87% for nitrites. Combined analysis of leucocyte esterase and/or nitrites and leucocyte esterase and nitrites showed no improvement in performance.ConclusionDipstick analysis is a reliable bedside test for ruling in UTI in children under 12 months, particularly in the presence of positive nitrites for children less than 3 months of age. Urine culture remains necessary for diagnostic confirmation.Article summaryThis study adds to the diagnostic performance of dipstick urinalysis in infants and neonates, with a specificity of 92%–99% and positive predictive value of 82%–96%.

Dipstick urinalysis shows high specificity but low sensitivity for UTI in febrile infants under 12 months

Study Details

Standardized formal resuscitation training likely reduces neonatal mortality in low- and middle-income countries compared to no training or basic training.

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Dipstick urinalysis shows high specificity but low sensitivity for UTI in febrile infants under 12 months

Study Details

Standardized formal resuscitation training likely reduces neonatal mortality in low- and middle-income countries compared to no training or basic training.

A Simple Training Program Is Saving Newborn Lives in Poor Countries

Clinical research that matters. Delivered to your inbox.

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