Acute Fatty Liver of Pregnancy - Clinical Manifestations

Clinical Manifestations

Acute fatty liver of pregnancy (or hepatic lipidosis of pregnancy) usually manifests in the third trimester of pregnancy, but may occur any time in the second half of pregnancy, or in the puerperium, the period immediately after delivery. On average, the disease presents during the 35th or 36th week of pregnancy. The usual symptoms in the mother are non-specific including nausea, vomiting, anorexia (or lack of desire to eat) and abdominal pain; however, jaundice and fever may occur in as many as 70% of patients.

In patients with more severe disease, pre-eclampsia may occur, which involves elevation of blood pressure and accumulation of fluid (termed edema). This may progress to involvement of additional systems, including acute renal failure, hepatic encephalopathy, and pancreatitis. There have also been reports of diabetes insipidus complicating this condition.

Many laboratory abnormalities are seen in acute fatty liver of pregnancy. Liver enzymes are elevated, with the AST and ALT enzymes ranging from minimal elevation to 1000 IU/L, but usually staying in the 300-500 range. Bilirubin is almost universally elevated. Alkaline phosphatase is often elevated in pregnancy due to production from the placenta, but may be additionally elevated. Other abnormalities may include an elevated white blood cell count, hypoglycemia, elevated coagulation parameters, including the international normalized ratio, and decreased fibrinogen. Frank disseminated intravascular coagulation, or DIC, may occur in as many as 70% of patients.

Abdominal ultrasound may show fat deposition in the liver, but, as the hallmark of this condition is microvesicular steatosis (see pathology below), this may not be seen on ultrasound. Rarely, the condition can be complicated by rupture or necrosis of the liver, which may be identified by ultrasound.