Is neutrophil gelatinase associated lipocalin useful in hepatitis C virus infection?

Aim: To evaluate neutrophil gelatinase associated lipocalin (NGAL) in patients infected by hepatitis C virus (HCV) before and during treatment with directly acting antivirals (DAAs).
Methods: NGAL was measured in a group of patients with chronic HCV infection ranked, at baseline, by age, gender, anti-hypertensive therapy, HCV viral load, liver fibrosis stage and, either at baseline or after 1 year, estimated glomerular filtration rate (eGFR). Then, NGAL and eGFR evolutions were monitored in a subgroup of patients who started antiviral therapy with DAAs. Differences of median NGAL levels were evaluated through Wilcoxon-Mann-Whitney test for non-parametric data. Differences in dichotomous variables were evaluated through χ (2) test. At baseline, a univariate regression analysis was conducted to verify if NGAL values correlated with other quantitative variables [age, fibrosis four (FIB-4), AST to platelet ratio index (APRI), and eGFR].
Results: Overall, 48 patients were enrolled, 8 of them starting HCV treatment. At baseline, statistically significant differences were found in median NGAL values only between patients with eGFR < 60 mL/min vs patients with eGFR ≥ 90 mL/min. Differences in NGAL were not significant among patients ranked by HCV viral load, FIB-4 score and APRI, when patients with NGAL > 118.11 ng/dL were compared with those of NGAL ≤ 118.11 ng/dL, not statistically significant differences were present for age, gender, chronic kidney disease classification and liver fibrosis (P > 0.05). Linear correlation was found between NGAL and both age (P = 0.0475) and eGFR (P = 0.0282) values. Not statistically significant predictions of NGAL at baseline were demonstrated for eGFR evolution 1 year later. Interestingly, in the 8 patients treated with DAAs, median NGAL significantly increased at week 12 compared to baseline (P = 0.0239).
Conclusion: Our results suggest that NGAL should be further evaluated as an adjunct marker of kidney function in these patients.