Impaired fatty acid oxidation as a cause of liver disease associated with hyperemesis gravidarum

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

Role of 3-Hydroxy Fatty Acid-Induced Hepatic Lipotoxicity in Acute Fatty Liver of Pregnancy

Acute fatty liver of pregnancy (AFLP), a catastrophic illness for both the mother and the unborn offspring, develops in the last trimester of pregnancy with significant maternal and perinatal mortality. AFLP is also recognized as an obstetric and medical emergency. Maternal AFLP is highly associated with a fetal homozygous mutation (1528G>C) in the gene that encodes for mitochondrial long-chain hydroxy acyl-CoA dehydrogenase (LCHAD). The mutation in LCHAD results in the accumulation of 3-hydroxy fatty acids, such as 3-hydroxy myristic acid, 3-hydroxy palmitic acid and 3-hydroxy dicarboxylic acid in the placenta, which are then shunted to the maternal circulation leading to the development of acute liver injury observed in patients with AFLP. In this review, we will discuss the mechanistic role of increased 3-hydroxy fatty acid in causing lipotoxicity to the liver and in inducing oxidative stress, mitochondrial dysfunction and hepatocyte lipoapoptosis. Further, we also review the role of 3-hydroxy fatty acids in causing placental damage, pancreatic islet β-cell glucolipotoxicity, brain damage, and retinal epithelial cells lipoapoptosis in patients with LCHAD deficiency.

Plasma Free Fatty Acids in Hyperemesis Gravidarum Pregnancy

We evaluated the free fatty acids differences in plasma between hyperemesis gravidarum(HG) and healthy pregnant in first trimester pregnancy.

OBJECTIVE

We aimed to compare the plasma levels of DHA, AA and EPA, between HG patients and healthy pregnant women.

DESIGN

Fifty-two pregnants were involved in the study. Twenty-six pregnants of them were HG as study group, and twenty-six pregnants were enrolled as healthy pregnant women at the similar gestational age. The saturated fatty acids C14, C15, C16, C18, C20, C22, and C24; the omega-3 fatty acids eicosapentaenoic acid, (EPA) and docosahexaenoic acid, (DHA); the omega-6 fatty acids linoleic acid, arachidonic acid (AA), and homo-gamma-linolenic acid; and the omega-9 fatty acids oleic acid, erucic acid, and nervonic acid were analysed by gas chromatography.

RESULTS

Statistically differences was not seen between the groups with maternal age, gestational age, or plasma levels of EPA, DHA, and AA. Statistically significant difference was seen between the groups with plasma levels of C20 and C22(p<0.05). C20 was declined but C22 was rised in the HG patients.

CONCLUSION

EPA, DHA, or AA, which related to placental and fetal neural development are not changing from Hyperemesis gravidarum.

Differences in Liver Injury and Trophoblastic Mitochondrial Damage in Different Preeclampsia-like Mouse Models

Background:

Preeclampsia is a multifactorial disease during pregnancy. Dysregulated lipid metabolism may be related to some preeclampsia. We investigated the relationship between triglycerides (TGs) and liver injury in different preeclampsia-like mouse models and their potential common pathways.

Methods:

Preeclampsia-like models (Nw-nitro-L-arginine-methyl ester [L-NAME], lipopolysaccharide [LPS], apolipoprotein C-III [Apo] transgnic mice + L-NAME, β2 glycoprotein I [βGPI]) were used in four experimental groups: L-NAME (LN), LPS, Apo-LN and βGPI, respectively, and controls received saline (LN-C, LPS-C, Apo-C, βGPI-C). The first three models were established in preimplantation (PI), early-, mid- and late-gestation (EG, MG and LG). βGPI and controls were injected before implantation. Mean arterial pressure (MAP), 24-hour urine protein, placental and fetal weight, serum TGs, total cholesterol (TC) and pathologic liver and trophocyte changes were assessed.

Results:

MAP and proteinuria were significantly increased in the experimental groups. Placenta and fetal weight in PI, EP and MP subgroups were significantly lower than LP. Serum TGs significantly increased in most groups but controls. TC was not different between experimental and control groups. Spotty hepatic cell necrosis was observed in PI, EG, MG in LN, Apo-LN and βGPI, but no morphologic changes were observed in the LPS group. Similar trophoblastic mitochondrial damage was observed in every experimental group.

Conclusions:

Earlier preeclampsia onset causes a higher MAP and urine protein level, and more severe placental and fetal damage. Preeclampsia-like models generated by varied means lead to different changes in lipid metabolism and associated with liver injury. Trophoblastic mitochondrial damage may be the common terminal pathway in different preeclampsia-like models.

Nausea and Vomiting During Pregnancy is Highly Heritable

Nausea and vomiting during pregnancy (NVP) affects about 70 % of all expectant mothers and commonly impacts their physical health and psychosocial functioning. The aim of this study was to estimate the heritability of the presence, duration and severity of NVP. The sample consisted of 1723 women (M age = 41.78, SD = 11.67) including twins in both complete and incomplete pairs and their sisters from two cohorts participating in the NVP Genetics Consortium. The sample comprised 159 monozygotic and 140 dizygotic complete twin pairs, and 69 twin-sister pairs. We applied an extended twin design using OpenMx and Mx for secondary analysis. Individual differences in NVP were best explained by additive genetic and unique environmental effects. Heritability estimates were 73 % (95 % CIs = 57-84 %) for presence, 51 % (95 % CIs = 36-63 %) for duration and 53 % (95 % CIs = 38-65 %) for severity of NVP. The genetic correlation between duration and severity was almost perfect. Our results show that genes play an important role in different aspects of NVP and justify the importance of searching for genetic variants.

Advances in understanding and treating liver diseases during pregnancy: A review

Liver disease in pregnancy is rare but pregnancy-related liver diseases may cause threat to fetal and maternal survival. It includes pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes, and low platelets syndrome; acute fatty liver of pregnancy; hyperemesis gravidarum; and intrahepatic cholestasis of pregnancy. Recent basic researches have shown the various etiologies involved in this disease entity. With these advances, rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival. The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention. Therefore, correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis. Therefore, here we review and summarized recent advances in understanding the etiologies, clinical courses and management of liver disease in pregnancy. This information will contribute to physicians for diagnosis of disease and optimum management of patients.

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.

Liver diseases in pregnancy: Diseases unique to pregnancy

Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver. Liver disease can cause significant morbidity and mortality in both pregnant women and their infants. This review summarizes liver diseases that are unique to pregnancy. We discuss clinical conditions that are seen only in pregnant women and involve the liver; from Hyperemesis Gravidarum that happens in 1 out of 200 pregnancies and Intrahepatic Cholestasis of Pregnancy (0.5%-1.5% prevalence), to the more frequent condition of preeclampsia (10% prevalence) and its severe form; hemolysis, elevated liver enzymes, and a low platelet count syndrome (12% of pregnancies with preeclampsia), to the rare entity of Acute Fatty Liver of Pregnancy (incidence of 1 per 7270 to 13000 deliveries). Although pathogeneses behind the development of these aliments are not fully understood, theories have been proposed. Some propose the special physiological changes that accompany pregnancy as a precipitant. Others suggest a constellation of factors including both the mother and her fetus that come together to trigger those unique conditions. Reaching a timely and accurate diagnosis of such conditions can be challenging. The timing of the condition in relation toward which trimester it starts at is a key. Accurate diagnosis can be made using specific clinical findings and blood tests. Some entities have well-defined criteria that help not only in making the diagnosis, but also in classifying the disease according to its severity. Management of these conditions range from simple medical remedies to measures such as immediate termination of the pregnancy. In specific conditions, it is prudent to have expert obstetric and medical specialists teaming up to help improve the outcomes.

Change in paternity and recurrence of hyperemesis gravidarum

OBJECTIVE

To determine whether change in paternity changes recurrence risk of hyperemesis gravidarum (HG).

STUDY DESIGN

Survey data on recurrence of HG was compared between cases who had a paternity change between pregnancies and cases who did not.

RESULTS

The percentage of HG pregnancies in women with the same partner for all pregnancies was not significantly different from the percentage of HG pregnancies in women who changed partners for at least one pregnancy (78% vs 71%, p > 0.05). Participants who did and did not change partners between their first and second pregnancies, were asked to rate their first and second pregnancy in regards to symptoms of HG. Neither the ratings nor the change in rating between pregnancies was significantly different between the two groups.

CONCLUSION

Women reported HG in over 70% of their pregnancies regardless of a paternity change. Paternal genes expressed through the fetus do not have a significant effect on incidence or recurrence of HG. This study supports a strong maternal genetic factor involved in HG. However, because the recurrence risk is not 100%, other factors play a role. Identification of the predisposing gene(s) and other factors will determine the cause of this poorly understood complication of pregnancy.

Recurrence risk of hyperemesis gravidarum

INTRODUCTION

The purpose of this study is to describe the recurrence risk for hyperemesis gravidarum (HG).

METHODS

Women who registered on a Web site sponsored by the Hyperemesis Education and Research Foundation as having had one HG-complicated pregnancy were contacted to follow-up on a subsequent pregnancy. Participants completed an online survey.

RESULTS

One hundred women responded. Fifty-seven had become pregnant again, 2 were trying to conceive, 37 were not willing to get pregnant again because of HG, and 4 did not have a second pregnancy for other reasons. Among the 57 women who responded that they had become pregnant again, 81% reported having severe nausea and vomiting in their second pregnancy. Among the women reporting recurrent HG, 98% reported losing weight and taking prescribed medication for HG, 83% reported treatment with intravenous fluids, 20% reported treatment with total parenteral nutrition or nasogastric tube feeding, and 48% reported hospitalization for HG.

DISCUSSION

This study demonstrates both a high recurrence rate of HG and a large percentage of women who change reproductive plans because of their experiences with HG.

Familial aggregation of hyperemesis gravidarum

OBJECTIVE

This study was undertaken to determine whether there is familial aggregation of hyperemesis gravidarum (HG), making it a disease amenable to genetic study.

STUDY DESIGN

Cases with severe nausea and vomiting in a singleton pregnancy treated with intravenous hydration and unaffected friend controls completed a survey regarding family history.

RESULTS

Sisters of women with HG have a significantly increased risk of having HG themselves (odds ratio, 17.3; P = .005). Cases have a significantly increased risk of having a mother with severe nausea and vomiting; 33% of cases reported an affected mother compared to 7.7% of controls (P < .0001). Cases reported a similar frequency of affected second-degree maternal and paternal relatives (18% maternal lineage, 23% paternal lineage).

CONCLUSION

There is familial aggregation of HG. This study provides strong evidence for a genetic component to HG. Identification of the predisposing gene(s) may determine the cause of this poorly understood disease of pregnancy.

Pregnancy-associated liver disorders

Liver disorders associated with pregnancy include hyperemesis gravidarum (HG), intrahepatic cholestasis of pregnancy (ICP), preeclampsia, syndrome of hemolysis, elevated liver enzymes and low platelets (HELLP), and acute fatty liver of pregnancy (AFLP). These conditions are relatively common and unique to pregnancy and are more likely to occur at certain terms of gestation specific to each condition. They can be associated with significant maternal and fetal morbidity and mortality. Although managing such patients may be very challenging, spontaneous resolution of the disease occurs shortly after termination of the pregnancy, usually without hepatic sequellae. Early diagnosis and timely treatment is a key to therapeutic success. This article explores the clinical features, pathophysiology, and management of these disorders.

High prevalence of severe nausea and vomiting of pregnancy and hyperemesis gravidarum among relatives of affected individuals

OBJECTIVE

The goal of this study was to determine the prevalence of severe nausea and vomiting of pregnancy/hyperemesis gravidarum among relatives of affected individuals.

STUDY DESIGN

Family history data were obtained on 1224 self-reported cases of hyperemesis gravidarum. Cases completed an online survey administered by the Hyperemesis Education and Research Foundation between 2003 and 2006.

RESULTS

Approximately 28% of cases reported their mother had severe nausea and vomiting or hyperemesis gravidarum while pregnant with them. Of the 721 sisters with a pregnancy history, 137 (19%) had hyperemesis gravidarum. Among the most severe cases, those requiring total parenteral nutrition or nasogastric feeding tube, the proportion of affected sisters was even higher, 49/198 (25%). Nine percent of cases reported having at least two affected relatives including sister(s), mother, grandmother, daughters, aunt(s), and cousin(s).

CONCLUSION

There is a high prevalence of severe nausea and vomiting of pregnancy/hyperemesis gravidarum among relatives of hyperemesis gravidarum cases in this study population. Because the incidence of hyperemesis gravidarum is most commonly reported to be 0.5%, this study provides strong but preliminary evidence for a genetic component to extreme nausea and vomiting of pregnancy.

Review on hyperemesis gravidarum

Hyperemesis gravidarum is severe, intractable nausea and vomiting affecting 0.3-2% of pregnancies. It has a complex multifactorial aetiology. This review explores the current literature relating to the clinical manifestations, differential diagnosis, epidemiology, possible aetiology, maternal and fetal complications, and evidence-based management of hyperemesis.

Expanded newborn screening of inherited metabolic disorders by tandem mass spectrometry: Clinical and laboratory aspects

Newborn screening started in the 1960s for the purpose of identifying phenylketonuric patients to begin early intervention and to prevent mental retardation in these patients. Soon thereafter, screening programs expanded to include additional genetic disorders added individually one at a time. In the 1980s, tandem mass spectrometry (MS/MS) was introduced in clinical laboratories, and in the 1990s, the technique was used for newborn screening. Unlike measuring one analyte at a time, MS/MS allows measurement of >40 analytes, in a few minutes with the use of a single assay. Currently, MS/MS is being used for the identification of several amino acid, organic acid and fatty acid disorders. Several states in the United States and many other countries are using MS/MS in newborn screening. However, there is a significant disparity among different newborn screening programs for disorders being screened by MS/MS and many other challenges are faced by the expanded newborn screening. It is anticipated that in the future the use of MS/MS in newborn screening will expand both at the analyte and geographic levels. Clinicians and laboratory scientists should become familiar with MS/MS, disorders being screened in their patients' population and the future of this emerging technology.