Urinary neutrophil gelatinase-associated lipocalin does not improve diagnostic accuracy in adult urinary tract infections: a prospective diagnostic accuracy study
Diagnostic Microbiology and Infectious Disease, cilt.116, sa.3, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 116 Sayı: 3
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.diagmicrobio.2026.117495
- Dergi Adı: Diagnostic Microbiology and Infectious Disease
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE, Environment Index, MEDLINE, Academic Search Ultimate (EBSCO)
- Anahtar Kelimeler: Urinary tract infection, Urinary NGAL, Biomarker, Complicated urinary tract infection, C -reactive protein, White blood cell count
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Background: Reliable biomarkers are needed to support the early diagnosis of UTI. This study investigated the diagnostic value of urinary Neutrophil Gelatinase-Associated Lipocalin (uNGAL) and conventional inflammatory markers in the diagnosis and differentiation of UTI types. Methods: In this prospective study (2024–2025), 259 adults with positive urine cultures were classified as having asymptomatic bacteriuria, uncomplicated UTI, complicated UTI, recurrent UTI, or catheter-associated UTI according to the 2025 IDSA Complicated UTIs Guideline. uNGAL was measured by ELISA. Results: uNGAL levels were numerically higher in UTI patients than controls (p=0.458). uNGAL levels did not show significant discrimination between controls and UTI subtypes (p=0.643). uNGAL levels were slightly higher in patients with recurrent UTI than in those without recurrent UTI and in patients with catheter-associated UTI than in non-catheterized patients (p=0.657 and p=0.058, respectively). Although NGAL could not distinguish complicated from uncomplicated UTI (p=0.272), CRP and WBC levels were significantly higher in complicated UTI (median 21 vs. 6 mg/L, p< 0.001; median 9800 vs. 7300 /mm³, p< 0.001, respectively). ROC analysis identified optimal cut-off values of 10.5 mg/L for CRP and 7850/mm³ for WBC; with sensitivities of 65% and 76% and specificities of 75% and 60%, respectively. Multivariate analysis showed that each 10 mg/L increase in CRP and each 1000/mm³ increase in WBC was associated with a 1.2 fold higher likelihood of complicated UTI. Conclusion: uNGAL does not provide diagnostic value beyond conventional inflammatory markers and should not be used as a standalone biomarker in adult UTI. CRP and WBC remain more reliable markers for predicting complicated UTI.