Critical Care and Shock

The validity of urinary neutrophil gelatinase-associated lipocalin (NGAL) as a biomarker of acute kidney injury in pediatric patients with sepsis

Abstract

Background: Septic patients with acute kidney injury (AKI) are associated with increased morbidity and mortality compared to septic patients without AKI. These usually occur within 24 hours of admission into ICU. The measurement of serum creatinine is usually used to diagnose AKI. However, the concentrations do not change until a decline in kidney function has reached 50% or less within a few days. Many studies have shown urinary neutrophil gelatinase-associated lipocalin (NGAL) as a predictor of AKI with different cut-off points.

Objective: This study aimed to determine the cut-off point of urinary NGAL in predicting the occurrence of AKI in pediatric septic patients within 48 to 72 hours after being admitted into ICU.

Methods: This was an observational analytic study with prospective longitudinal design, carried out on patients who met the inclusion and exclusion criteria at the resuscitation room in the Emergency Room (ER) at Dr. Soetomo Hospital Surabaya. The urine was taken at the 0th, 6th, 12th, and 24th hours for urinary NGAL examination. Every procedure taken on each patient was recorded and followed until the third day to determine factors correlated with AKI.

Result: Of the total 41 pediatric septic patients, 30 met the inclusion and exclusion criteria and about 56.7% had AKI. The urinary NGAL at 0th hour had significant value. A cut-off point of 1242 ng/ml was a better determinant of the incidence of AKI with a sensitivity of 76.5%, specificity of 61.5%, area under the curve (AUC) of 0.715, and relative risk of 2.2. Furthermore, the urinary NGAL at 0th hour was able to differentiate each level of AKI. Yet, the urine values of NGAL at 6th, 12th, and 24th hours were invalid as predictor of AKI.

Conclusion: Urinary NGAL at 0th hour is a valid predictor of occurrence of AKI grades 1, 2, and 3 in pediatric septic patients 48-72 hours after being admitted into the hospital.