Acute kidney injury in pediatric acute liver failure, decompensated liver disease and acute-on-chronic liver failure: pathophysiology, challenges, and management strategies

Abstract Acute kidney injury (AKI) occurs frequently in children with liver disease, especially those with paediatric acute liver failure (PALF) and acute-on-chronic liver failure (PALF). Existing evidence suggests that AKI in these populations is more prevalent than in the overall population of critically ill children. There are many triggers for AKI, including systemic inflammation, hypoperfusion, drug-induced nephrotoxicity, and, in children with cirrhosis with ascites, hepatorenal syndrome-AKI (HRS-AKI) can develop. At present, the diagnosis of AKI most commonly relies on the KDIGO (Kidney Disease: Improving Global Outcomes) criteria; however, due to reliance on serum creatinine, this may lead to misclassification in a subcohort of children with liver disease. Clinician awareness of patient- and liver failure-specific risk factors for AKI is vital, to ensure optimised care from the point of hospital admission to reduce the likelihood of subsequent AKI and associated morbidity andmortality. Management in general is primarily supportive, ensuring careful fluid management, targeted use of vasopressors, and renal replacement therapy where appropriate. Novel biomarkers show promise for future diagnosis and prognostication, and extrapcorporeal therapies to assist in enhanced management. Overall, considering the significant differences in pathology in children versus adults with acute and chronic liver disease, more research is urgently needed.