NGAL as a biomarker for early diagnosis of acute kidney injury in the ICU

Background: Acute kidney injury (AKI) is common in ICU patients, leading to longer hospitalizations and higher mortality. Early detection and prevention are key to improving outcomes. This study aimed to assess pNGAL and SCysC as early diagnostic and prognostic markers for AKI severity, and mortality. Methods: This prospective observational study included ICU patients with septicemia, heart failure, ketoacidosis, and those on nephrotoxic drugs like aminoglycosides. Serum creatinine, pNGAL, and SCysC were measured within 4-h of admission, then at 24-h and 48-h for pNGAL and SCysC. SCr was monitored for 7 days. Results: Plasma NGAL and SCysC were significantly elevated in AKI patients as compared with non-AKI patients; at baseline, 24-h and at 48-h (p<0.001), demonstrating good sensitivity and specificity (AUC of 0.913 and 0.888 at baseline, respectively). PNGAL and SCysC levels were significantly correlated with serum creatinine. Plasma NGAL and SCysC levels were highly significant in deceased patients and patients with multiple comorbidities. Conclusion: pNGAL and SCysC are promising biomarkers for AKI. They can predict AKI in our setting before SCr levels rise, enabling timely interventions to help reduce the associated mortality and morbidity. Elevated pNGAL and SCysC in patients with multiple comorbidities may indicate worse prognosis and severity. Monitoring these markers in ICU patients with multiple comorbidities can help prevent irreversible kidney injury.