Acute fatty liver of pregnancy

A rare, serious liver disorder occurring in pregnancy

Acute fatty liver of pregnancy
Synonyms	AFLP
Pronounce
Field	Obstetrics, Perinatology, Hepatology
Symptoms	Nausea, vomiting, abdominal pain (especially in the right upper quadrant), jaundice, headache, malaise, anorexia, confusion
Complications	Liver failure, renal failure, hypoglycemia, disseminated intravascular coagulation, fetal distress or death
Onset	Usually in the third trimester of pregnancy
Duration	Acute onset, resolves after delivery
Types
Causes	Defective mitochondrial fatty acid oxidation; most commonly due to long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHAD) in the fetus
Risks	Multiple pregnancy, first pregnancy, male fetus, carrying a fetus with LCHAD deficiency, previous history of AFLP
Diagnosis	Clinical presentation, liver function tests, coagulation profile, ultrasound, biopsy (rarely needed), Swansea criteria
Differential diagnosis	HELLP syndrome, preeclampsia, viral hepatitis, intrahepatic cholestasis of pregnancy, acute pancreatitis
Prevention	No definitive prevention; genetic counseling may be considered for high-risk cases
Treatment	Immediate delivery of the baby, supportive care (IV fluids, glucose, blood products)
Medication	Supportive only; no specific drug treatment
Prognosis	Good with early diagnosis and prompt delivery; maternal mortality <10% with modern care
Frequency	Rare (1 in 7,000 to 1 in 20,000 pregnancies)
Deaths	Maternal and fetal mortality can occur if untreated

Acute fatty liver of pregnancy (AFLP) is a rare but serious condition characterized by the accumulation of fat in the liver of pregnant women. It typically occurs in the third trimester of pregnancy and can lead to liver failure if not promptly diagnosed and treated. AFLP is considered a medical emergency and requires immediate attention to prevent severe complications for both the mother and the fetus.

Pathophysiology

The exact cause of acute fatty liver of pregnancy is not fully understood, but it is believed to be related to a defect in the metabolism of fatty acids. This defect leads to the accumulation of fat in the liver cells, causing liver dysfunction. Genetic factors, such as mutations in the mitochondrial enzyme long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD), have been implicated in the development of AFLP. This enzyme is crucial for the oxidation of fatty acids, and its deficiency can result in the accumulation of toxic metabolites.

Clinical Presentation

AFLP typically presents in the third trimester of pregnancy, often between 30 and 38 weeks of gestation. Symptoms can be nonspecific and may include:

• Nausea and vomiting
• Abdominal pain, particularly in the right upper quadrant
• Jaundice
• Malaise and fatigue
• Anorexia
• Headache
• Confusion or altered mental status

In severe cases, AFLP can progress to liver failure, coagulopathy, renal failure, and encephalopathy.

Diagnosis

The diagnosis of acute fatty liver of pregnancy is primarily clinical, supported by laboratory findings and imaging studies. Key laboratory findings include:

• Elevated liver enzymes (AST, ALT)
• Elevated bilirubin levels
• Hypoglycemia
• Coagulopathy (prolonged prothrombin time)
• Leukocytosis

Imaging studies, such as ultrasound or MRI, may show an enlarged liver with increased echogenicity, but these findings are not specific to AFLP.

Management

The primary treatment for AFLP is the prompt delivery of the fetus, as this is the only definitive cure. Supportive care is also crucial and may include:

• Intravenous fluids and glucose to manage hypoglycemia
• Blood products to correct coagulopathy
• Monitoring and support of renal and hepatic function

In severe cases, admission to an intensive care unit may be necessary. Postpartum, liver function typically improves rapidly after delivery.

Prognosis

With early diagnosis and appropriate management, the prognosis for both mother and child can be favorable. However, delayed treatment can lead to significant maternal and fetal morbidity and mortality. Recurrence in subsequent pregnancies is rare but possible, especially if there is an underlying genetic predisposition.

Related pages

• Liver disease
• Pregnancy complications
• Liver failure
• Jaundice