Acute on chronic liver failure (ACLF) is a distinct clinical entity; however, there is still debate in the way it is defined in the East as compared to the West, especially with respect to incorporation of kidney dysfunction or failure in the definition of ACLF. Kidney dysfunction is defined as serum creatinine between 1.5 and 1.9 mg/dl and kidney failure as serum creatinine of more than 2 mg/dl or requirement of renal replacement therapy according to the EASL-CLIF Consortium. Kidney dysfunction or failure is universally present in patients with ACLF according to the definition by the EASL-CLIF Consortium while on the contrary the APASL definition of ACLF does not incorporate kidney dysfunction or failure in its definition. Recently, both the diagnosis and management of renal failure in patients with cirrhosis has changed with the advent of the acute kidney injury (AKI) criteria defined as an abrupt decline in renal functions, characterized by an absolute increase in serum creatinine of 0.3 mg/dl within 48 h or an increase of more than 50 % from baseline, which is known or presumed to have occurred in the previous 7 days. Further, recent studies in patients with cirrhosis have shown the utility of biomarkers for the diagnosis of AKI. The present review covers the pathogenetic mechanisms, diagnosis, prognosis as well as management of AKI in patients with ACLF from both a Western as well as an Eastern perspective. The review identifies an unmet need to diagnose AKI and prevent this ominous complication in patients with ACLF.
Keywords: ACLF; AKI; APASL; EASL-CLIF.