Differentiating Asymptomatic Bacteriuria From Urinary Tract Infection in the Pediatric Neurogenic Bladder Population: NGAL As a Promising Biomarker.

To evaluate whether urinary antimicrobial peptides (AMPs) can discriminate between asymptomatic bacteriuria (ASB) and urinary tract infection (UTI) in pediatric patients with neurogenic bladder (NGB). Bladder urine was collected from pediatric patients (≤18 years old) with NGB without augmentation cystoplasty. Patients were divided into the following groups based on symptomatology and results of urinalysis/urine culture: (a) UTI, (b) ASB, and (c) sterile. Urine AMPs β defense 1 (BD-1), neutrophil gelatinase-associated lipocalin (NGAL), cathelicidin (LL-37), hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein (HIP/PAP), and human α defensin 5 (HD-5) were compared between groups by enzyme-linked immunosorbent assays. In addition, urines from pediatric controls without NGB or UTI were also analyzed. Significance was determined using Student's test for parametric or Mann-Whitney test for nonparametric data. A value of <.05 was considered significant. Thirty-six patients with NGB from a spinal dysraphism were evaluated: UTI, = 6; ASB, = 18; sterile, = 12. These groups did not differ significantly by age but did significantly differ by gender ( = .0139). NGAL significantly differed between UTI and ASB groups (median 38.5 ng/mg vs 15.5 ng/mg, respectively; = .0197) with a sensitivity and specificity of 82.4% and 83.3%, respectively. HIP/PAP, BD-1, HD-5, LL-37, and NGAL levels were all significantly higher in sterile NGB urines compared to 17 non-NGB pediatric controls ( < .0001, = .0020, = .0035, = .0006, and = .0339, respectively). All five urinary AMPs evaluated were significantly elevated in NGB patients compared to controls. NGAL levels may help differentiate between UTI and ASB in pediatric NGB patients.