Clinical Pearls & Morning Reports
Published December 21, 2022
Hemangiomas and focal nodular hyperplasia of the liver, as well as hepatic adenomas, can grow as a result of estrogen exposure during pregnancy. Read the NEJM Case Records of the Massachusetts General Hospital here.
Q: Is subcapsular hematoma a common complication of the HELLP (hemolysis, elevated liver-enzyme levels, and low platelet count) syndrome?
A: HELLP syndrome can be complicated by formation of a subcapsular hematoma, although such an event is rare (<1% of cases). The pathophysiological process of subcapsular hematoma formation is thought to start with microangiopathy and vasospasm that in turn lead to the development of ischemic intrahepatic lesions. Neovascularization is complicated by hemorrhage in the context of labile hypertension. This intrahepatic blood collects in the subcapsular space, which can cause pain as Glisson’s capsule stretches and can even lead to capsular rupture with potentially catastrophic intraabdominal hemorrhage.
Q: What enzyme deficiency is associated with acute fatty liver of pregnancy?
A: Acute fatty liver of pregnancy is an uncommon complication — occurring in 1 in 1000 to 1 in 35,000 deliveries — that results from an accumulation of fatty acid metabolites in hepatocytes due to defects in fatty acid metabolism. Acute fatty liver of pregnancy can be associated with fetal long-chain 3-hydroxyacyl–coenzyme A dehydrogenase deficiency. If the fetus is homozygous for the genetic mutation that causes this enzyme deficiency and the mother is therefore an obligate carrier, fatty acid metabolites build up in the fetal liver and ultimately in the maternal liver. Acute fatty liver of pregnancy is associated with marked liver dysfunction that leads to clinically significant hypoglycemia, elevated bilirubin levels, thrombocytopenia, and elevations in liver-function test results, which are typically many times as high as the upper limit of the normal range.
A: Hepatic adenomas, although uncommon overall, are more common among women than among men and are up to 30 or 40 times as common among long-term users of oral contraceptives as among those who do not use oral contraceptives. Hepatic adenomas are also known to grow as a result of estrogen exposure during pregnancy and are complicated by bleeding in up to 30% of cases. Risk factors for bleeding include pregnancy and a large lesion; lesions larger than 5 cm are considered to confer a higher risk. Also, adenomas on the left side of the liver (segments 2 and 3) are more than twice as likely to bleed as those on the right side.
A: There are three main subtypes of hepatic adenomas: the subtype associated with mutation of HNF1A (the gene that encodes hepatocyte nuclear factor 1A), the subtype associated with beta-catenin activation, and the inflammatory subtype. The inflammatory subtype is associated with elevated levels of inflammatory markers in the blood and is also the subtype that is most likely to cause bleeding. Hepatic adenomas are typically painless lesions, but may be painful in the context of acute bleeding and stretching of the liver capsule.