BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker in the detection of kidney injury. Early diagnosis of urinary tract infection (UTI), one of the most common infections in children, is important in order to avert long-term consequences. We assessed whether serum NGAL (sNGAL) or urine NGAL (uNGAL) would be reliable markers of UTI and evaluated the appropriate diagnostic cutoff value for the screening of UTI in children. METHODS: A total of 812 urine specimens and 323 serum samples, collected from pediatric patients, were analyzed. UTI was diagnosed on the basis of culture results and symptoms reported by the patients. NGAL values were measured by using ELISA. RESULTS: NGAL values were more elevated in the UTI cases than in the non-UTI cases, but the difference between the values were not statistically significant (P=0.190 for sNGAL and P=0.064 for uNGAL). The optimal diagnostic cutoff values of sNGAL and uNGAL for UTI screening were 65.25 ng/mL and 5.75 ng/mL, respectively. CONCLUSIONS: We suggest that it is not appropriate to use NGAL as a marker for early diagnosis of UTI in children.
Acute-Phase Proteins/*urine ; Area Under Curve ; Biological Markers/blood/urine ; Child ; Child, Preschool ; Early Diagnosis ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Infant ; Lipocalins/*blood/*urine ; Male ; Mass Screening/*methods ; Proto-Oncogene Proteins/*blood/*urine ; ROC Curve ; Urinary Tract Infections/*blood/*urine