Introduction
We evaluated the novel urinary neutrophil gelatinase-associated lipocalin (NGAL) as an early biomarker that rapidly releases in acute kidney injury (AKI) complicating circulatory shock.
Methods
We measured the urinary NGAL level from collected urine in 45 patients with circulatory shock, during the first 6 hours and after 24 hours. Eleven patients responded to fluid infusion ± vasopressors and were considered as a separate control group.
Results
The estimated urinary NGAL at day 1 and day 2 post circulatory shock could predict AKI presented at days 2 and 3 and days 3 and 4 (P < 0.05, P < 0.001 and P < 0.001, P < 0.001) respectively. Apart from all conventional kidney parameters and biomarkers, significant inverse correlations could be detected only between urinary NGAL at days 1 and 2 with the corresponding urine output in the patient group (r = -0.51 and -0.64, P < 0.05 and P < 0.001, respectively). The best cut-off value of urinary NGAL at day 1 was 26 ng/ml, for which sensitivity was 62% and 69% and specificity was 75% and 80% for prediction of AKI presented at days 2 and 3, respectively. While the best cut-off at day 2 was 29 ng/ml, for which sensitivity was 70% and 74% and specificity was 90% and 80% for prediction of AKI presented at days 3 and 4, respectively. Urinary NGAL at day 2 could significantly predict mortality complicating AKI rather than at day 1 (P < 0.05).
Conclusion
Urinary NGAL seems to be a potential early and sensitive biomarker for AKI and a persistently increased level at day 2 can predict mortality following circulatory shock.