Review Question - QID 214975

This pregnant patient presenting with nausea, vomiting, severe abdominal pain, hyperammonemia, and profound hypoglycemia in the setting of elevated aminotransferases and thrombocytopenia most likely has acute fatty liver disease of pregnancy (AFLP).

AFLP is a rare disease typically occurring in the third trimester of pregnancy presenting as acute liver failure secondary to extensive microvesicular fatty infiltration of the liver. It is due to failure of fatty acid beta-oxidation and presents with right upper quadrant pain, nausea, vomiting, and jaundice. Like other pregnancy-related disorders of the liver (pre-eclampsia and HELLP syndrome), AFLP presents with elevated aminotransferases and a leukocytosis. AFLP is distinguished by signs of acute-onset fulminant liver failure manifesting through laboratory findings of hypoglycemia, thrombocytopenia, hyperammonemia, and possible disseminated intravascular coagulopathy. Patients with AFLP can decompensate quickly with multi-organ failure and fetal compromise. Management is immediate delivery.

Natarajan et al. review the role of 3-hydroxy fatty acid-induced hepatic lipotoxicity in AFLP. The authors find that maternal AFLP is highly associated with a mutation in mitochondrial long-chain hydroxy acyl-CoA dehydrogenase. The authors recommend further study of the effects of 3-hydroxy fatty acids in causing placental toxicity and fetal retinal pigmented epithelial lipoapoptosis.

Incorrect Answers:
Answer 1: Acetaminophen toxicity can present with signs of fulminant liver failure, although laboratory values are typically notable for aminotransferase values > 1000 U/L. This patient’s symptoms preceded her ingestion of acetaminophen.

Answer 3: Eclampsia is a pregnancy disorder defined as pre-eclampsia (hypertension > 140/90 mmHg and proteinuria > 300 mg/24 hours among other features) with new-onset seizures. While this patient is hypertensive, she also has a normal urinalysis and signs of fulminant liver failure which would be unexplained by eclampsia alone.

Answer 4: Hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome also causes hepatic inflammation and can present similarly with right upper quadrant pain, vomiting, thrombocytopenia, and elevated aminotransferases in a patient with pre-eclampsia. HELLP syndrome can be distinguished from AFLP because it lacks the symptoms of acute liver failure (hyperammonemia, hyperbilirubinemia, and hypoglycemia) found in patients with AFLP.

Answer 5: Preeclampsia is a hypertensive pregnancy disorder that typically occurs during the third trimester. It is defined as hypertension (systolic blood pressure > 140 mmHg or diastolic blood pressure > 90 mmHg) and proteinuria (> 300 mg/24 hours) among other features.

Bullet Summary:
Acute fatty liver disease of pregnancy develops during the third trimester and presents with abdominal pain, vomiting, and laboratory findings of acute fulminant liver failure (hyperbilirubinemia, hyperammonemia, hypoglycemia, thrombocytopenia, and elevated aminotransferases).