Urine neutrophil gelatinase associated lipocalin (NGAL) in septic versus non-septic acute kidney injury

Background: Sepsis is the most common trigger for acute kidney injury (AKI) in critically ill patients. This study is to monitor changes in urine neutrophil gelatinase- associated lipocalin (uNGAL levels between septic and non-septic AKI and also to evaluate differences between septic and non-septic AKI with uNGAL. Material and methods: This was a prospective observational study of critically ill patients with acute kidney injury (AKI) Patients were evaluated for presenting complaints and on evaluation those who satisfied for SIRS criteria are taken up for study. In those patients with evidence of infection and positive for at least two criteria for SIRS are taken up as cases (n=30) and rest are taken as controls (n=30). All the patients were serially monitored for urine output, renal parameters, urine NGAL, APACHE II score and SOFA score. Patient urine was collected immediately after admission followed by 12, 24 and 48 hours for measuring NGAL. Results: Mean change in NGAL (ng/ml) at 12 hour, 24 hour and 48 hour was -12.5±5, -20.5±6.74 and -29.3±10.25 respectively in septic AKI and was -0.94±6.08, -0.92±6.31 and -0.10±6.12 respectively in non septic AKI. Within group analysis showed statistically high significance (p<0.0001) in septic AKI but not in non septic AKI group (P=0.97). On evaluating between group analysis, we found significantly high difference of NGAL in septic AKI at 12 hrs, 24 hrs and 48 hrs as compared to non septic AKI (P<0.0001) Conclusion: Septic AKI patients have higher detectable urine NGAL compared with non-septic AKI patients. These differences in NGAL values in septic AKI may have diagnostic and clinical relevance as well as pathogenetic implications.