Urine endothelin-1 as a Biomarker for Urinary Tract Infections in Children

Kee, Hyung Min; Yi, Dae Yong; Yun, Ki Wook; Lim, In Seok

Abstract

PURPOSE
Urinary tract infections (UTIs) are the most common source of bacterial infections in infants and young children. Accurate diagnosis and treatment is important because of their association with renal scarring, which can lead to complications. Urine endothelin-1 (ET-1) is the major renal isoform produced and released by renal mesangial cells in response to glomerular injury. This study aimed to investigate whether urinary levels of ET-1 can be used as a biomarker for UTI diagnosis.
METHODS
We conducted a prospective study using medical records of 70 patients below the age of 18 years, who visited Chung-Ang University Hospital from July 2012 to July 2013. We classified the patients into the UTI and control groups based on urine culture studies. The UTI group was further divided into upper and lower UTI groups using 99m-Technetium dimercaptosuccinic acid scintigraphy. Urine ET-1 was measured using enzyme linked immunosorbent assay with 0.3 mL urine.
RESULTS
The UTI and control groups were comprised of 45 and 25 patients, respectively. Mean urine ET-1 levels were significantly higher in the UTI group than in the control group (1.41+/-0.35 pg/mL vs. 0.33+/-0.07 pg/mL, P=0.04). There was no significance difference in the quantitative value between the upper and lower UTI groups (P=0.552). There was no correlation between urine ET-1 and serum C-reactive protein (Pearson correlation [R]=0.24), urine ET-1 and serum white blood cell count (R=0.19).
CONCLUSION
Our study suggests that urine ET-1 can be used for early diagnosis of UTI in children.