Acute Fatty Liver of Pregnancy: Pathophysiology, Anesthetic Implications, and Obstetrical Management

Abstract

(Anesthesiology. 2019;130:446–461) As health care providers become more aware of acute fatty liver of pregnancy, more mild cases have been diagnosed and diagnosis is occurring earlier. Anesthesiologists must understand the pathophysiology and the obstetric impact to properly manage this condition.

Fever, cough and gastrointestinal symptoms in a pregnant woman

“…Overlapping of diagnostic parameters pose a serious challenge in excluding HLH from other clinical entities (Table 1). [1][2][3][4] Furthermore, management in each of these clinical diseases is entirely different. High-dose corticosteroids, etoposide, cyclosporin, rituximab and intravenous immunoglobulin have been used successfully to treat acquired HLH.…”

“…Differential diagnosis included several common medical and surgical pathologies: acute fatty liver of pregnancy, HELLP (haemolysis, elevated liver enzymes and low platelets) syndrome, miliary/ abdominal tuberculosis, haemolytic anaemia, visceral leishmaniasis and lymphomas. [1][2][3][4] A complete blood count showed white cell counts of 3,000 cells/mm 3 (neutrophils; 65%), platelet count of 94,000 cells/mm 3 and a haemoglobin level of 8.4 g/dL. Liver function tests revealed total bilirubin of 4.6 mg/dL, direct bilirubin of 2.4 mg/dL, aspartate aminotransferase of 122 U/L and alanine transferase of 30 U/L.…”

Acute Fatty Liver Disease of Pregnancy in the Second Trimester

“…To understand the pathophysiology of AFLP, the importance of the normal change of metabolism of fatty acids seen in pregnancy is crucial. During a normal pregnancy, there is a physiologic decrease in the oxidation of both long and medium chain fatty acids which subsequently lead to an increased maternal level of fatty acids during the course of the pregnancy, thus predisposing patients to the hepatotoxic effects of fatty acids [6]. Levels of free fatty acids increase particularly late in gestation which may explain why AFLP most commonly occurs in the third trimester.…”

“…More recently, our understanding of AFLP has improved after the close relation of fetal fatty acid oxidation disorders to maternal acute fatty liver disease. More specifically, the fetal deficiency of the enzyme long-chain 3-hydroxyacylcoenzyme A dehydrogenase (LCHAD) which is a component of the mitochondrial beta-oxidation of fatty acids causes accumulation of long fatty acids [1,6]. These same fatty acids can then cross over to the maternal circulation.…”

“…This can then not only trigger the hepatotoxic effects to the maternal liver but also affect the mother's own mitochondrial betaoxidation leading to further accumulation of free fatty acids. The incidence of liver disease can be as high as 75% in mothers who carry fetuses with LCHAD [6].…”