Alteraciones hepáticas durante el embarazo

Abstract

During pregnancy, biochemical evaluation of the liver is affected in many significant ways. Alkaline phosphatase increases in the third trimester and rapidly returns to the normal limits after delivery. This increase is clearly secondary to the placental isoenzyme. AST and ALT are usually normal and GGTP doesn't changes significantly. Hepatic flow remains unchanged and estrogen levels increase leading to several metabolic and cutaneous changes, such as hepatic palms and systemic vasodilatation. Liver diseases that occur during pregnacy can be classified as follows: a) Entities exclusive of pregnancy, b) Pregnancy associated diseases, and c) Previous liver diseases.

The first group included: 1. Cholestasis of pregnancy, described mainly in Scandinavian and Chilean women and characterized by pruritus in the third trimester, biochemical evidence of cholestasis, increased frequency of cholclitiasis and fetal problems. The entity usually recurs in other pregnancies or during exposure to estrogens. Prognosis is good and the patient improves rapidly after delivery. Several reports have shown that s-Adenosyl-Methionine can be effective. 2) Hyperemesis gravidarum, characterized by protracted vomiting associated to significant malnutrition. Liver function tests are usually abnormal and the liver biopsy shows no specific changes. Prognosis is usually good Hígado y embarazo and most of the patients improved spontaneously. 3) Acute fatty liver, is one of the causes of liver failure during the third trimester and is associated with a very high maternal mortality. Clinically the patient presents with encephalopathy, biochemical evidence of liver failure and microvesicular fat in the liver. Prognosis is good if detected early, and the correct treatment is interruption of pregnancy. 4) Hepatic abnormalities related to toxemia such as: fibrin deposits along the hepatic sinusoids, portal and periportal hemorraghes and in severe cases ischemic necrosis in focal areas. Spontaneous hepatic rupture and the Hellp syndrome (hemolysis, liver enzyme abnormalities and low platelets) have been described.

The second group is associated with the following entities: 1) Viral hepatitis, the most common cause of jaundice in pregnancy Hepatitis A being the most frequent, and associated with prematurity and neonatal mortality. Vertical transmission doesn't occurs. Hepatitis B is also seen, and clearly associated with vertical transmission in the third trimester. When the mother is HBeAg positive the risk of transmission is about 90%. In order to prevent neonatal infection hepatitis B vaccine and gammaglobulin must be administered to the newborn in the first 12 hours. Efficacy is more than 90%. Alcohol intake during pregnancy is associated with the fetal-alcohol syndrome and cirrhosis in general is a common cause of infertility in women, usually causes decompensation with increase frequency of bleeding varices and ascites. Finally familiar hyperbilirubinemias are frequently aggravated, with elevation of bilirubin in the Dubin-Johnson syndrome.