Urine neutrophil gelatinase-associated lipocalin (NGAL) as an initial biomarker of acute kidney injury (AKI) in an intensive care unit (ICU) patients: a preliminary study

Background: Acute kidney injury (AKI) is one of the complications in critical patients that can increase morbidity and mortality.The condition of AKI is reversible and must be detected as early as possible.One of a potential marker for early detection is urine Neutrophil gelatinase-associated lipocalin (NGAL).This study aims to evaluate urine NGAL as an early AKI detection marker among critically ill patients.Methods: This is an observational prospective cohort study involving 39 patients who were admitted to the Intensive care unit (ICU) of Dr. Sardjito General Hospital Yogyakarta during June-August 2018.The inclusion criteria were ICU patients with age>19 years old, and exclusion criteria were chronic renal failure and kidney transplantation.The AKI established based on an increase in serum creatinine levels ≥0,3 mg/dl in 48 hours or urine volume <0.5 ml /kg/hour in 6 hours.Mann Whitney test, Spearman correlation, and Chi-Square were used for statistical analysis.Data were analyzed using SPSS version 17 for windows.Results: The results showed that there were no significant differences between the urine NGAL levels of AKI and non-AKI patients (130 (85-177) ng/dL; 56.65 (2.8-1500) ng/dL, p=0.407).In this study, only 3 cases of AKI were obtained from 39 subjects.Further analysis was carried out by looking at the correlation between urine NGAL levels and urine leukocyte count.The results showed a moderate correlation between them (r=0.6,p=0.001).The proportion of patients with elevated urine NGAL levels was greater in the group of patients with elevated urine leukocyte counts compared to the group with normal urine leukocyte counts (86,7%; 13,3%, p=0,008).).Conclusions: Evaluation of urinary NGAL application as an early marker of AKI was not optimal in this study.An increase of urine leukocytes interfered urine NGAL.