Plasma Exchange and Continuous Renal Replacement Therapy in the Treatment of Acute-on-Chronic Liver Failure Patients with Acute Kidney Injury

Background: The prognosis for patients with acute-on-chronic liver failure (ACLF) complicated by acute kidney injury (ACLF-AKI) is poor. Plasma exchange (PE) is one of the primary treatments, while continuous renal replacement therapy (CRRT) is essential for improving AKI. Objectives: A retrospective analysis was conducted to study the prognosis of patients with ACLF-AKI who underwent PE and were treated with CRRT. Methods: Patients with ACLF-AKI who were admitted to the First Affiliated Hospital of Soochow University from August 2015 to August 2018 were included: Sixty eight received medication-only treatments (group A), 56 received PE treatments (group B), and 74 received PE + CRRT treatments (group C). The patients' clinical data were compared using the LSD-t-test, Kruskal-Wallis test, and chi-square test. Multivariate survival analysis was performed using the Cox proportional hazards regression model. Results: One hundred ninety-eight patients were enrolled in the study. The levels of glomerular filtration rate (eGFR) and creatinine clearance rate (Ccr) in groups B and C were significantly different after treatment. The MELD-Na score decreased notably (Z = -2.81, Z = -3.67, t = 6.07, all P < 0.05 in group B; Z = -5.81, Z = -4.05, t = -6.90 in group C, all P < 0.05), and there was no significant difference in eGFR, Ccr levels, and MELD-Na scores between groups B and C after treatment (all P > 0.05). COX proportional risk regression model analysis revealed that the impact on survival indicators for ACLF-AKI patients is the levels of eGFR and Ccr after blood purification treatment and the MELD-Na score (all P-values < 0.05). The risk of death and the cumulative risk increased with prolonged hospitalization. Conclusions: Combination therapy can improve renal damage in patients with ACLF-AKI, but it offers no advantage over PE alone. Renal function post-purification treatments influences prognosis, and the risk of mortality and hospitalization rises over time.