Acute fatty liver of pregnancy is uncommon, but a possibly life-threatening disorder of pregnancy that primarily develops in the third trimester. Jaundice, fever, abdominal pain, anorexia, and nausea are some of the main complaints, whereas liver failure and coagulopathy can lead to both maternal and fetal death in the absence of proper therapy. Clinical findings, a thorough laboratory evaluation, and a liver biopsy are vital components of the diagnostic workup, while imaging studies are of limited benefit.
Described as a rare entity in clinical practice (seen in 1 in 10,000-15,000 pregnancies) , acute fatty liver of pregnancy (AFLP) is a disorder of still incompletely understood etiology that is encountered in the third trimester of pregnancy or in early postpartum period     . Microvesicular steatosis (accumulation of fat) in the liver, but without any inflammation or necrosis, is the main pathophysiological event that is responsible for the development of symptoms and associated complications, but the mechanisms leading to its occurrence remain unclear  . The clinical presentation is nonspecific - jaundice is the most common symptom, followed by fever, nausea, vomiting, anorexia, malaise, abdominal pain and tenderness in the upper right or middle epigastric area   . Additional findings include proteinuria, hypertension, and edema (which manifest as polyuria and polydipsia, and are highly suggestive of preeclampsia), whereas altered consciousness, seizures, respiratory insufficiency that requires assisted ventilation, as well as ascites, may develop rapidly without early therapy . Furthermore, various complications of acute fatty liver of pregnancy have been described in the literature - liver failure, gastrointestinal bleeding (as a result of coagulopathies that arise from impaired liver function), renal failure, pancreatitis, hypoglycemia, disseminated intravascular coagulation (DIC) and hepatic encephalopathy  . Despite the fact that the majority of women improve their general condition within the first month postpartum  , deaths from this condition have been reported, especially if preeclampsia or other comorbidities are concomitantly present .
The life-threatening risk of AFLP mandates the physician to include this condition in the differential diagnosis of nonspecific constitutional symptoms accompanied by jaundice. But because this condition is strikingly similar to viral hepatitis, preeclampsia, cholestasis, HELLP syndrome (hemolysis, elevated liver enzymes, low platelet count) and several other hepatic disorders, a thorough investigation is necessary. Some authors have illustrated the important role of a properly obtained patient history and a detailed physical examination that can rule out some of the mentioned diseases based on clinical findings (For example, jaundice is rarely seen in preeclampsia, and cholestasis is not associated with nausea and vomiting) . Laboratory findings, however, provide more definite diagnostic clues. Elevated liver transaminase levels (alanine and aspartate aminotransferases, or ALT and AST, respectively), hypoglycemia, leukocytosis, hyperbilirubinemia, hypoglycemia, increased prothrombin time (PT) and/or partial thromboplastin time (aPTT), increased values of creatinine, and hyperammonemia are some of the main laboratory criteria of acute fatty liver of pregnancy  . Imaging studies, such as computed tomography (CT) and abdominal ultrasonography, are of limited use in the diagnosis of AFLP, which is why a liver biopsy is considered to be the gold standard, but it can only be performed in the setting of hemodynamic stability    .