- January 11, 2016
- Posted by: emobile
- Category: Trending Issues
Preeclampsia/hypertension-related liver diseases and pregnancy
Preeclampsia is defined as hypertension and proteinuria after 20 weeks of pregnancy and within 48 hours of delivery. It complicates 10% of pregnancies. It is a multisystem disorder, and the liver is involved in 20–30% of preeclampsia cases. It is the most common cause of liver dysfunction and hepatic tenderness in pregnancy.
Liver involvement is secondary to vasospasm of the hepatic vascular bed. Aminotransferase levels are usually elevated mildly up to 10 times normal values; however, they might occasionally be elevated up to 20 times normal values. Jaundice occurs only occasionally (5%) and the bilirubin level is usually <5 mg/dL. Liver involvement in preeclampsia is an indicator of the severity of preeclampsia, and no specific therapy for liver involvement is required. Nearly 3% of pregnancies are complicated by liver disorders. Liver disorders during pregnancy are classified as those related to pregnancy and those just coincidental (occurring during pregnancy or pre-existing). Pregnancy-related disorders are the most common causes of liver dysfunction during pregnancy and are further divided into those associated with or without preeclampsia. Hyperemesis gravidarum (HG), intrahepatic cholestasis of pregnancy (ICP), preeclampsia, HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome, and acute fatty liver of pregnancy (AFLP) are conditions affecting the liver that are unique to pregnancy. Pregnancy-related liver disorders display characteristic trimester-specific clustering in their occurrence, whereas coincidental liver disorders can occur at any time.
HG complicates 0.3–2.0% of pregnancies . It is characterized by intractable vomiting in the first trimester (typically 4–10 weeks), leading to dehydration, ketosis, and weight loss of ≥5%, necessitating hospitalization. HG is not a liver disease in the strict sense, but it leads to liver dysfunction in 50% of cases. The mechanism of liver involvement in HG is multifactorial and not well understood. Transient hyperthyroidism is seen in 60% of cases . This form of gestational transient thyrotoxicosis is not associated with any unfavorable pregnancy outcome and does not require any treatment. HG-associated liver dysfunction should be a diagnosis of exclusion. A woman presenting with liver dysfunction with or without HG in the first trimester must be carefully investigated to rule out other causes of liver dysfunction (viral hepatitis and drug-induced liver injury).
Management of HG is supportive and includes intravenous rehydration with a short period of fasting, followed by reintroduction of a diet rich in carbohydrates and low in fat. Antiemetics such as dopamine antagonists (metoclopramide and domperidone), phenothiazines (chlorpromazine and prochlorperazine), or antihistamine H1 receptor antagonists (cyclizine and promethazine) are used safely during pregnancy . Thiamine supplementation is given with dextrose infusion, particularly in women with a history of prolonged (over weeks) vomiting, to prevent Wernicke’s encephalopathy.