Acute kidney injury associated with acute fatty liver of pregnancy: An update on a rare clinical entity

Acute fatty liver of pregnancy (AFLP) is a rare but potentially life-threatening liver disease associated with mitochondrial dysfunction. It is characterized by microvesicular hepatic steatosis and typically occurs in the third trimester, though it may rarely present postpartum. AFLP is considered a non-thrombotic microangiopathy (TMA) but may present with overlapping TMA features. Its incidence ranges from 1 in 7000 to 1 in 20000 pregnancies, although milder cases may go unrecognized. AFLP can rapidly progress to acute liver failure and 20% to 40% of affected women exhibit clinical features of preeclampsia. Acute kidney injury (AKI) is a frequent complication, observed in 55% to 75% of AFLP cases, which is significantly higher than the 7% to 20% occurrence seen in preeclampsia or hemolysis, elevated liver enzymes, and low platelets syndrome. The exact mechanism behind AKI in AFLP remains unclear, but renal histology has shown tubular deposits of free fatty acids, which correlate with current theories regarding liver pathology. While AFLP-associated AKI is often reversible after delivery, some patients may develop persistent AKI that requires dialysis. Therapeutic plasma exchange (TPE) has been explored in these cases, but available evidence is limited. This review summarizes the current understanding of the epidemiology, pathophysiology, clinical features, and management of AKI in the context of AFLP, and discusses the potential role of adjunctive therapies such as TPE.