Neutrophil gelatinase-associated lipocalin predicts the efficacy of tolvaptan for ascites in patients with liver cirrhosis

Background Acute kidney injury (AKI) is associated with liver cirrhosis (LC), water retention, diuretics to treat water retention, and a poor prognosis. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) reportedly predicts a poor prognosis in decompensated LC. This study investigated the usefulness of uNGAL in predicting the short- and long-term effects of tolvaptan (TVP) and the incidence of AKI post-TVP administration. Methods Of the LC cases with water retention, 86 with available pre-treatment uNGAL were analyzed. A short-term response was defined as weight loss of ≥ 1.5 kg within the first week; a long-term response was defined as a short-term response without early recurrence. The uNGAL usefulness in predicting the short- and long-term effects of TVP and AKI incidence post-TVP administration was investigated. Results Short-term effects of TVP were observed in 52 patients. Of these, 15 patients had an early recurrence. In multivariate analysis, significant short-term predictive factors were C-reactive protein (CRP) < 1.4 mg/dl, uNa/K ratio ≥ 3.51, and uNGAL < 50.2 ng/ml. Patients were classified according to these three cut-off values, with short-term response rates of 92.9%, 68.8%, 26.7%, and 0% for 0, 1, 2, and 3 points, respectively. CRP < 0.94 mg/dl and uNGAL < 50.2 ng/ml were significant factors for predicting the long-term response of TVP. The AKI incidence post-TVP was 8.1% ( n = 7) and was significantly higher among those with uNGAL ≥ 38.1 ng/mL. Conclusion uNGAL is a useful predictor of the short- and long-term efficacy of TVP and can be useful in predicting AKI incidence post-TVP administration.