Abstract: SA-PO430
Urinary NGAL as a Risk Factor for Recurrence of Febrile Urinary Tract Infection in Children
Session Information
- Pediatric Nephrology - II
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1600 Pediatric Nephrology
Authors
- Yamanouchi, Sohsaku, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
- Kimata, Takahisa, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
- Akagawa, Yuko, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
- Akagawa, Shohei, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
- Tsuji, Shoji, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
- Kaneko, Kazunari, Kansai Medical University, Hirakata-shi, OSAKA-FU, Japan
Group or Team Name
- Department of Pediatrics, Kansai Medical University
Background
Urinary neutrophil gelatinase-associated lipocalin (NGAL) has received attention recently as a sensitive biomarker of acute kidney injury. However, its ability to protect endogenously against urinary tract infection (UTI) is lesser known. That is, NGAL, which is expressed and secreted from activated neutrophils, acts as an iron chelator and antibacterial peptide that suppresses the growth of Escherichia coli and other bacteria. Purpose: To prove the hypothesis that reduced NGAL expression causes recurrence of febrile UTI (fUTI) in children.
Methods
The subjects were 45 children who were diagnosed as having fUTI and treated at our institution from 2012 to 2016 (median age, 1.5 years; 34 boys). We measured their urinary NGAL levels in the non-infected stage (at least 4 months since fUTI recovery). To examine risk factors for recurrence of fUTI, the subjects were divided into a non-recurrent group (24 cases) and a recurrent group (21 cases) according to the presence or absence of fUTI over 1 year. The following items were examined as risk factors: age, sex, presence or absence of grade III or higher vesicoureteral reflux (VUR; all cases received preventive antibiotics), presence or absence of renal scarring, and urinary biomarkers (NGAL and β2-microglobulin). The urinary biomarkers were corrected for creatinine (Cr) level.
Results
In a multiple logistic regression analysis, significant differences between the groups were not observed for age, sex, renal scarring, or β2-microglobulin/Cr level, while the recurrent group had significantly more cases with grade III or higher VUR (p < 0.01). Furthermore, the urinary NGAL/Cr in the recurrent group (median, 3.2 μg/gCr; interquartile range, 2.0–4.0 μg/gCr) was significantly lower than that in the non-recurrent group (median, 16 μg/gCr; interquartile range, 11–20 μg/gCr; p = 0.016). We then created the ROC curve to examine the cut off value of NGAL for predicting recurrence of fUTI. In the area under the ROC curve, which was calculated for NAGL/Cr, was 0.86. Cut off value of 7.6 μg/gCr appeared to have the best predicting accuracy yielding a specificity of 81% and a sensitivity of 88%.
Conclusion
Reduced level of urinary NGAL, which functions to protect endogenously against UTI, is a risk factor of recurrence of fUTI and thus could serve as a biomarker.