Assessment of acute kidney injury at hospital admission in cirrhosis: estimating baseline serum creatinine is not the answer

Overestimated renal function in patients with liver cirrhosis predicts poor prognosis

AIM

A high prevalence of overestimated renal function in patients with liver cirrhosis (LC) has been reported; nonetheless, its impact on prognosis remains unclear. We aimed to evaluate the impact of overestimated renal function on prognosis in patients with LC.

METHODS

An overestimated renal function was defined as a >20% increase in the creatinine-based estimated glomerular filtration rate (eGFR), compared with cystatin C-based eGFR. LC patients with conserved serum, who were evaluated for muscle atrophy and had proper clinical information were included, and their prognostic factors were analyzed.

RESULTS

A total of 215 consecutive patients with LC were included. The prevalence of overestimated renal function was 29.8% (64/215). Kaplan-Meier survival analysis revealed that patients with overestimated renal function had a poorer prognosis than those without overestimated renal function (hazard ratio [HR]: 2.217 95% confidence interval [CI]: 1.290-3.810; p = 0.001). Subgroup analysis showed that overestimated renal function was a significant prognostic factor, irrespective of sex and the presence of hepatocellular carcinoma (HCC). Multivariate Cox regression analyses revealed that overestimated renal function was a significant and independent factor predictive of poor prognosis in the entire cohort (HR: 2.050; 95% CI: 1.041-4.037; p = 0.038) and in subgroups classified by Child-Pugh class A (HR: 2.131; 95% CI: 1.019-4.458; p = 0.044), Model for End-Stage Liver Disease score ≤9 (HR: 2.303; 95% CI: 1.038-5.109; p = 0.04), and presence of HCC (HR: 2.290; 95% CI: 1.128-4.651; p = 0.022).

CONCLUSION

Overestimated renal function is a significant and independent prognostic factor in patients with LC.

Changes in the estimated renal function after hepatitis C virus eradication with direct-acting antiviral agents: Impact of changes in skeletal muscle mass

Hepatitis C virus (HCV) infection can cause renal dysfunction, expected to improve upon HCV eradication. However, adverse effects of HCV eradication using direct-acting antiviral agents (DAAs) on renal function have been recently reported. This retrospective study aimed to evaluate renal function with glomerular filtration rate (eGFR) estimated using creatinine (eGFRcre) and cystatin C (eGFRcys). Complete clinical information and preserved serum samples were collected from 207 patients with HCV infection treated with interferon-free DAA at baseline and SVR48 (SVR48). Patients who underwent paired computed tomography (CT) at baseline and ≥12 months after DAA were evaluated for changes in skeletal muscle mass using the psoas muscle mass index (PMI). eGFRcre significantly worsened at SVR48, while eGFRcys was similar at baseline and SVR48. At baseline, eGFRcre was significantly higher than eGFRcys; eGFRcre and eGFRcys were similar at SVR48. Multivariate analysis revealed that the presence of liver cirrhosis and low-albumin level, as well as cirrhosis and age, was significantly associated with the overestimation of renal function by eGFRcre at baseline and SVR48, respectively. In the 57 patients who underwent paired CT at baseline and ≥12 months after DAA, relative values of PMI significantly increased after DAA. After DAA, in patients with increased PMI (65% 37/57), eGFRcre significantly worsened but did not change in patients without increased PMI. eGFRcre significantly worsened after DAAs; however, this might not reflect accurate changes in renal function, partially because of changes in skeletal muscle mass. eGFRcys did not change after DAAs, and it is a potential alternative to eGFRcre.

Could KIM-1 and NGAL levels predict acute kidney injury after paracentesis? - preliminary study

BACKGROUND

Kidney dysfunction is a common complication in patients with severe liver cirrhosis. There is a need for discovery and validation of novel biomarkers for earlier AKI detection. The aim of this study was to determine if tubular injury markers: NGAL and KIM-1 could be helpful in the early diagnosis of AKI in patients undergoing therapeutic paracentesis.

METHODS

This preliminary study included 24 adult patients diagnosed with liver cirrhosis who had been hospitalized due to massive ascites requiring paracentesis. Pre- and post-paracentesis plasma samples were taken from each patient and biomarkers were measured.

RESULTS

Before paracentesis, the levels of serum and urinary NGAL were similar between patients and controls; while urinary KIM-1 was markedly increased in liver cirrhotic patients (0.76 vs. 0.24 ng/ml; respectively). Although urinary NGAL levels in AKI patients were 5-time greater than in non-AKI subgroup, the difference did not reach statistical significance (13.2 vs 1.5 pg/mL, p = 0.06). Serum NGAL level, post-procedure, was 3 times greater in AKI subgroup.

CONCLUSION

Kidney injury markers, especially serum NGAL, may be useful for the early detection of AKI. However, further research is required to determine if biomarkers of kidney injury may help identify patients with cirrhosis who would most likely benefit from early AKI prevention and treatment.

Role of biomarkers as predictors of acute kidney injury and mortality in decompensated cirrhosis

Evidence suggests that novel biomarkers predict acute kidney injury (AKI) development and outcome earlier than serum creatinine. The aim of this study was to determine the incidence and prognosis of AKI in decompensated cirrhotic patients, and also assess the usefulness of plasma cystatin C, urine neutrophil gelatinase associated lipocalin (NGAL), tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) in early prediction of AKI and mortality. Single-center, prospective observational study enrolling decompensated cirrhotic patients without AKI at the time of admission. Of 111 patients with decompensated cirrhosis, 45 (40.5%) developed AKI while hospitalized. Even with 53.3% being transient (stage 1), mortality was significantly higher in AKI than non-AKI patients (46.5% vs. 25%, p = 0.02). Plasma cystatin C and urine NGAL, but not urine [TIMP-2]·[IGFBP7] at the time of admission were found to be independent early predictors of AKI. Substitution of cystatin C for creatinine significantly improved the model for end-stage liver disease (MELD) score accuracy for mortality prediction. The incidence of AKI is high and is associated with high mortality in decompensated cirrhotic patients. Plasma cystatin C and urine NGAL are useful for early detection of AKI. MELD-cystatin C, rather than original MELD, improves predictive accuracy of mortality.