Absence of the G1528C (E474Q) mutation in the alpha-subunit of the mitochondrial trifunctional protein in women with acute fatty liver of pregnancy

Pregnancy-Associated Liver Diseases

The liver disorders unique to pregnancy include hyperemesis gravidarum, intrahepatic cholestasis of pregnancy, acute fatty liver of pregnancy, and preeclampsia-associated hepatic impairment, specifically hemolysis, elevated liver enzymes, and low platelet count syndrome (HELLP). Their importance lies in the significant maternal and fetal/neonatal morbidity and mortality. Expeditious diagnosis and clinical evaluation is critical to ensure timely, appropriate care and minimize risks to the pregnant woman and her fetus/baby. A multidisciplinary approach is essential, including midwives, maternal-fetal-medicine specialists, anesthetists, neonatologists, and hepatologists.

Acute Fatty Liver of Pregnancy

Acute fatty liver of pregnancy is a rare, but potentially fatal obstetric disorder characterized principally by varying degrees of hepatic failure with an onset typically in late pregnancy. This review outlines the etiopathogenesis and describes the multiorgan involvement that often results in a number of clinical and laboratory aberrations. These laboratory derangements provide distinct features to differentiate from other obstetric complications, such as hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. Once recognized, central to the management of acute fatty liver of pregnancy is delivery planning and meticulous supportive care. One particularly dangerous complication is profound coagulopathy. After delivery, the coagulation defect resolves over 1-2 days, and hepatic and renal function are restored soon thereafter. This report offers anticipated recovery and management strategies for commonly associated complications. Application of these factors has served to decrease mortality from as high as 80% down to 10%; however, given the seriousness of this condition, severe maternal morbidities are frequently associated with this obstetric emergency.

Maternal and neonatal outcomes and prognostic factors in acute fatty liver of pregnancy

OBJECTIVE

To report complications of Acute Fatty Liver of pregnancy (AFLP), a rare liver disease of pregnancy, and identify prognostic factors for mothers and children.

STUDY DESIGN

We conducted a retrospective descriptive study over 18 years in three French maternities. Demographic, clinical, biological data, and outcomes of patients and their infants were reviewed.

RESULTS

142,450 pregnancies from centers were studied. Eighteen patients with AFLP were identified The prevalence of AFLP was estimated as 1/7,914 pregnancies. Prolonged prothrombin time was identified as a risk factor of maternal complications (OR = 0.86, p = 0.0493). Gestational age at delivery was the only risk factor associated with fetal or neonate complications (OR = 0.37, p = 0.0417). One boy died of previously undiagnosed β-oxidation deficiency at eight months.

CONCLUSION

In AFLP, prothrombin time must be carefully monitored to anticipate major maternal complications. Infants born to mothers with ALFP should be screened as early as possible for mitochondrial fatty acid oxidation deficiency.

Acute fatty liver of pregnancy and concomitant medical conditions: A review of cases at a quaternary obstetric hospital

Acute fatty liver of pregnancy is a rare complication of pregnancy that may result in fulminant hepatic failure. We present a review of all patients presenting to a quaternary obstetric hospital over a 15-year period, with particular regard to biochemical changes, results of gene testing, and pre-existing conditions. Seventeen patients with acute fatty liver of pregnancy were identified. Six patients were documented to have pre-existing gastrointestinal disease; five with inflammatory bowel disease, and one with influenza A hepatitis. Antithrombin III levels were low in this study, consistent with previously published data. There were no recurrences of acute fatty liver of pregnancy in nine subsequent pregnancies to seven mothers. The authors are not aware of any literature addressing pre-existing medical conditions which may predispose to acute fatty liver of pregnancy.

Acute fatty liver of pregnancy in a woman with ulcerative colitis and familial hidradenitis suppurativa

Acute fatty liver of pregnancy is a heterogeneous disorder which may occur in the absence of a detectable gene mutation for the enzyme long-chain L-3-hydroxyacyl-CoA dehydrogenase. Acute fatty liver of pregnancy has been reported to complicate several gastrointestinal disorders including viral hepatitis, chronic active hepatitis and intrahepatic cholestasis of pregnancy. A case of acute fatty liver of pregnancy in a woman with ulcerative colitis and familial hidradenitis suppurativa without a detectable gene mutation is presented. The potential role of inflammatory cytokines in precipitating acute fatty liver of pregnancy is discussed.

[Acute fatty liver of pregnancy and mitochondrial fatty acid oxidation. Consequences for the offspring]

Acute fatty liver of pregnancy (AFLP) is a rare liver disease unique to pregnancy that can lead to acute liver failure. The prognosis, initially often fatal for both mother and child, has been improved by prompt delivery. The diagnosis should be highly suspected if the mother presents epigastric pain, nausea and/or vomiting, or polyuria-polydipsia in the third trimester of pregnancy. AFLP has been found associated with a genetic deficiency of fatty acid beta-oxidation, which may cause sudden death in infancy. Consequently, the mother and her newborn should undergo screening for this deficiency.

Pregnancy-related liver disorders

Pregnancy-related liver disorders accounted for 8% of all maternal deaths at our center from 1999 to 2011. Of the three pregnancy-related liver disorders (acute fatty liver of pregnancy (AFLP), HELLP (Hemolysis, elevated liver enzymes, low platelets) syndrome and pre-eclamptic liver dysfunction, which can lead to adverse maternal and fetal outcome, AFLP is most typically under - diagnosed. Risk of maternal death can be minimised by timely recognition and early/aggressive multi-specialty management of these conditions. Urgent termination of pregnancy remains the cornerstone of therapy for some of these life threatening disorders, but recent advancements in our understanding help us in better overall management of these patients. This review focuses on various aspects of pregnancy-related liver disorders.

Acute fatty liver of pregnancy: clinical outcomes and expected duration of recovery

OBJECTIVE

Our aim was to provide a description of clinical and laboratory finding: pregnancy outcomes in women with acute fatty liver of pregnancy (AFLP). We also characterize the duration of recovery of multiorgan system dysfunction that begins after delivery.

STUDY DESIGN

All women who were admitted to Parkland Hospital with AFLP were identified; their clinical and laboratory findings, pregnancy outcomes, and postpartum resolution of AFLP were reviewed.

RESULTS

Between 1975 and 2012, there were 51 women who were identified to have AFLP. The most common complaints were persistent nausea and vomiting (57%), hypertension (57%), and abdominal pain (53%). More than 90% of these women had at least 1 of these findings or combinations thereof. A combination of hepatic and renal dysfunction was nearly universal, but with variable severity. Procoagulant synthesis was impaired in more than three-fourths of the women, which served to intensify obstetric hemorrhage for which 50% of the 51 women received blood and component transfusions. The stillbirth rate was 120 of 1000 pregnancies, and there were 2 maternal deaths. Composite recovery times of various markers of hepatic and renal function indicated normalization of most laboratory values within 7-10 days after delivery.

CONCLUSION

The clinical features and laboratory findings of women with AFLP derive from the central pathologic process: liver failure. After delivery, clinical recovery typically is seen within 3-4 days; however, laboratory abnormalities can persist for much longer.

Acute fatty liver of pregnancy: an update on mechanisms

Acute fatty liver of pregnancy (AFLP), characterized by hepatic microvesicular steatosis, is a sudden catastrophic illness occurring almost exclusively in the third trimester of pregnancy. Defective fatty acid oxidation in the fetus has been shown to be associated with this disease. Since the placenta has the same genetic makeup as the fetus and as AFLP patients generally recover following delivery, we hypothesized that the placenta might be involved in pathogenesis of this disease. In an animal model of hepatic microvesicular steatosis (using sodium valproate), we found that microvesicular steatosis results in mitochondrial structural alterations and oxidative stress in subcellular organelles of the liver. In placentas from patients with AFLP, we observed placental mitochondrial dysfunction and oxidative stress in subcellular organelles. In addition, defective placental fatty acid oxidation results in accumulation of toxic mediators such as arachidonic acid. Escape of these mediators into the maternal circulation might affect the maternal liver resulting in microvesicular steatosis.

Liver injury in acute fatty liver of pregnancy: possible link to placental mitochondrial dysfunction and oxidative stress

Acute fatty liver of pregnancy (AFLP) is a rare disorder which is fatal if not recognized and treated early. Delivery of the feto-placental unit results in dramatic improvement in maternal liver function, suggesting a role for the placenta. However, the mechanisms by which defects in the fetus or placenta lead to maternal liver damage are not well understood and form the focus of this study. Placenta and serum were obtained at delivery from patients with AFLP, and placental mitochondria and peroxisomes were isolated. Placental mitochondrial function, oxidative stress, and fatty acid composition as well as serum antioxidants, oxidative and nitrosative stress markers, and fatty acid analysis were carried out. Hepatocytes in culture were used to evaluate cell death, mitochondrial function, and lipid accumulation on exposure to fatty acids. Oxidative stress was evident in placental mitochondria and peroxisomes of patients with AFLP, accompanied by compromised mitochondrial function. Increased levels of arachidonic acid were also seen in AFLP placenta when compared to control. Patients with AFLP also had a significant increase in oxidative and nitrosative stress markers in serum, along with decreased antioxidant levels and elevated levels of arachidonic acid. These levels of arachidonic acid were capable of inducing oxidative stress in hepatocyte mitochondria accompanied by induction of apoptosis. Exposure to arachidonic acid also resulted in increased lipid deposition in hepatocytes.

CONCLUSION

Oxidative stress in placental mitochondria and peroxisomes is accompanied by accumulation of toxic mediators such as arachidonic acid, which may play a causative role in maternal liver damage seen in AFLP.

[Recurrent acute fatty liver of pregnancy]

Acute fatty liver of pregnancy (AFLP) is a rare liver disease unique to pregnancy potentially fatal for both mother and child. Only a few cases of recurrence have been published. We report a new case. A 27-year-old primiparous patient presented a first episode of AFLP in 1991 at 37 week's gestation. Diagnosis was suspected because of vomiting, thrombocytopenia, and liver function tests abnormalities. It was confirmed by liver ultrasonography and abdominal computed tomography. Clinical and biological improvement was observed after caesarean delivery. Six years later, the woman began a second pregnancy. Liver function tests and complete blood count were regularly checked. At 30 weeks' gestation, recurrent AFLP occurred and caesarean section was performed. Again, diagnosis was confirmed by both ultrasonography and abdominal computed tomography. In 2006, the mother and the two girls, 15 and 8-year-old respectively, were in good health. The study of the HADHA gene, coding alpha subunit long chain 3-hydroxyacyl coenzyme A dehydrogenase (LCHAD) in the patient failed to find mutations, particularly the common mutation c.1528G>C (Glu474-Gln, p.E474Q). In conclusion, after an episode of AFLP, women should be clearly warned of the risk of recurrence and regularly monitored during the next pregnancy, even if the search of HADHA gene mutation is negative.

Highly active antiretroviral therapy does not affect mitochondrial beta-oxidation of fatty acids: an in vitro study in fibroblasts

Preeclampsia is a multifactorial pregnancy-specific disease. In some cases, severe preeclampsia and related disorders of acute fatty liver of pregnancy and hemolysis, elevated liver enzymes, low platelets syndrome are associated with inherited defects in mitochondrial beta-oxidation of fatty acids, especially a deficiency of long-chain 3-hydroxyacyl coenzyme A dehydrogenase (LCHAD). Recently, an unexplained increase in the incidence of preeclampsia has been documented in human immunodeficiency virus (HIV)-infected pregnant women on treatment with highly active antiretroviral therapy (HAART). We performed this study to determine if antiretroviral drugs affect mitochondrial beta-oxidation fatty acids in vitro. Two normal and 1 heterozygous LCHAD-deficient cell lines were exposed to up to 5 times the therapeutic concentrations of the following antiretroviral drugs: nevirapine, didanosine, lamivudine, and a combination of nelfinavir, zidovudine, and lamivudine. One homozygous LCHAD-deficient cell line served as the positive control. After exposure of the fibroblasts to these drugs for periods ranging from 2 to 10 days, accumulations of even-chain 3-hydroxy fatty acids (3-OH-C6 to 3-OH-C18) in the culture media were measured by stable-isotope dilution gas chromatography/mass spectrometry. Compared to the respective unexposed fibroblasts, there was no significant build-up of 3-hydroxy fatty acids in the culture media of normal or heterozygous LCHAD-deficient fibroblasts exposed to antiretroviral drugs. Our results show that the commonly used antiretroviral drugs do not adversely affect fatty acid oxidation in fibroblasts. Therefore, an altered fatty acid oxidation may not be the mechanism for the reported increased risk of preeclampsia in HIV-infected pregnant women on HAART.

No mutation was found in the alpha-subunit of the mitochondrial tri-functional protein in one patient with severe acute fatty liver of pregnancy and her relatives

BACKGROUND AND AIM

Acute fatty liver of pregnancy (AFLP) is a serious hepatic disorder and a devastating late gestational complication associated with substantial maternal and neonatal morbidity and mortality. Several studies have demonstrated a strong association between AFLP in the mother and fetal deficiency of the enzyme long-chain L-3 hydroxyacyl-CoA dehydrogenase (LCHAD). LCHAD resides in the alpha-subunit of the mitochondrial tri-functional protein and catalyzes the third step in the beta-oxidation of fatty acids in the mitochondria. The aim of this study was to determine in one patient with severe AFLP who survived liver transplantation, if the infant or her parents would bear the common or rare mutation of the LCHAD gene.

METHODS

Genomic DNA was extracted from the patient with severe AFLP and her daughter and parents. Exon 15 of LCHAD was amplified by polymerase chain reaction (PCR) and analyzed by restricted fragment length polymorphism (RFLP) with Pst-I. The whole coding region of LCHAD cDNA of all subjects was amplified and sequenced for the potential rare mutation.

RESULTS

None of the subjects had the G1528C mutation in the LCHAD gene. None of the subjects had mutation in the whole coding region of LCHAD or rare polymorphisms.

CONCLUSIONS

Although this study was limited to one proband and her relatives, our observations suggest that there might be diverse etiological factors in China contributing to AFLP other than the frequently reported mutation in the LCHAD, and the metabolic basis for AFLP may be more heterogeneous than previously believed.

Homogeneous amplification nucleobase quenching assay to detect the E474Q LCHAD deficiency mutation

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is a rare and potentially fatal autosomal recessive disorder of fatty acid metabolism. Early institution of dietary therapy is essential and places a premium on rapid diagnosis. Pregnancy with an LCHAD-deficient fetus is often complicated in the third trimester by liver disease, particularly acute fatty liver of pregnancy. All cases of isolated LCHAD deficiency have at least one copy of the E474Q mutation in the gene encoding the alpha-subunit of the mitochondrial trifunctional protein. Previously published methods for detecting this mutation are based upon allele-specific restriction enzyme digestion of a DNA fragment generated by PCR, followed by gel electrophoresis to resolve the products. We have developed a faster and less expensive assay for the E474Q mutation using PCR followed directly by differential melting of a fluorescently labeled oligodeoxyribonucleotide probe, using nucleobase quenching to detect probe hybridization.

Lack of correlation between fatty acid oxidation disorders and haemolysis, elevated liver enzymes, low platelets (HELLP) syndrome?

AIM

Fatty acid beta-oxidation defects comprise a heterogeneous group of disorders that may precipitate acute life threatening metabolic crises particularly during catabolic episodes. Several studies have demonstrated a possible association between fatty acid beta-oxidation defects, including long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency and severe pregnancy complications. However, the precise percentage of women with haemolysis, elevated liver enzymes, low platelets (HELLP) syndrome associated with foetal fatty acid beta-oxidation defects is not known.

METHODS

We carried out a multicentre retrospective study on 88 infants, born to women with HELLP syndrome. Acylcarnitine profiles from blood dried on filter paper cards were analysed by tandem mass spectrometry for the diagnosis of fatty acid beta-oxidation defects. In addition, we screened for the common long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency mutation using a standard restriction fragment length polymorphism polymerase chain reaction method.

RESULTS

None of the infants studied carried the common long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency mutation. There was no evidence of fatty acid beta-oxidation defects, including long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, as expected by unremarkable acylcarnitine profiles, while three infants with fatty acid beta-oxidation defects were diagnosed in the control group.

CONCLUSIONS

Neither foetal long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, including heterozygosity for the common long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency mutation, nor fatty acid beta-oxidation defects in general are a major risk factor for HELLP syndrome in Austria.

The Association Between Acute Fatty Liver of Pregnancy and Fatty Acid Oxidation Disorders

Acute fatty liver of pregnancy is a relatively rare but potentially fatal liver disorder of late pregnancy. Recent advances in molecular diagnostic procedures provide evidence of a genetic basis for this condition and a link to offspring disorders in fatty acid oxidation. This relationship implies the need for genetic testing and follow-up of at-risk women and their neonates.