Bile Acid Determination after Standardized Glucose Load in Pregnant Women

[Intrahepatic cholestasis of pregnancy: French College of Obstetricians and Gynecologists guidelines for clinical practice]

OBJECTIVE

To identify strategies for reducing neonatal and maternal morbidity associated with intrahepatic cholestasis pregnancy (ICP).

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE methodology with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane, EMBASE and Google Scholar databases. The quality of the evidence was assessed (high, moderate, low, very low) and a (i) strong or (ii) weak recommendations or (iii) no recommendation were formulated. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Of the 14 questions (from 12 PICO questions and one definition question outside the PICO format), there was agreement between the working group and the external reviewers on 14 (100%). The level of evidence of the literature was insufficient to provide a recommendation on two questions. ICP is defined by the occurrence of suggestive pruritus (palmoplantar, nocturnal) associated with a total bile acid level>10μmol/L or an alanine transaminase level above 2N after ruling out differential diagnoses. In the absence of suggestive symptoms of a differential diagnosis, it is recommended not to carry out additional biological or ultrasound tests. In women with CIP, ursodeoxycholic acid is recommended to reduce the intensity of maternal pruritus (Strong recommendation. Quality of the evidence moderate) and to decrease the level of total bile acids and alanine transaminases. (Strong recommendation. Quality of the evidence moderate). S-adenosyl-methionine, dexamethasone, guar gum or activated charcoal should not be used to reduce the intensity of maternal pruritus (Strong recommendation. Quality of evidence low), and there is insufficient data to recommend the use of antihistamines (No recommendation. Quality of evidence low). Rifampicin (Weak recommendation. Very low quality of evidence) or plasma exchange (Strong recommendation. Very low quality of evidence) should not be used to reduce maternal pruritus and perinatal morbidity. Serum monitoring of bile acids is recommended to reduce perinatal morbidity and mortality (stillbirth, prematurity) (Low recommendation. Quality of the evidence low). The level of evidence is insufficient to determine whether fetal heart rate or fetal ultrasound monitoring are useful to reduce perinatal morbidity (No recommendation). Birth is recommended when bile acid level is above 99μmol/L from 36 weeks gestation to reduce perinatal morbidity, in particular stillbirth. When bile acid level is above 99μmol/L is below 100μmol/L, women should be informed that induction of labor could be considered 37 and 39 weeks gestation to reduce perinatal morbidity. (Strong recommendation. Quality of evidence low). In postpartum, total bile acids and alanine transaminases level should be checked and normalized before prescribing estrogen-progestin contraception, ideally with a low estrogen dose (risk of recurrence of pruritus and cytolysis) (Low recommendation. Quality of evidence very low).

CONCLUSION

Although the quality of evidence regarding ICP gestational cholestasis remains low, there is a strong consensus in France, as shown by our Delphi study, on how to manage women with ICP. The reference first-line treatment is ursodeoxycholic acid.

Intrahepatic cholestasis of pregnancy: a comparison of Society for Maternal-Fetal Medicine and the Royal College of Obstetricians and Gynaecologists' guidelines

This study reviewed the literature regarding the diagnosis, antepartum surveillance, and timing of delivery of pregnancies complicated by intrahepatic cholestasis of pregnancy, comparing the guidelines published by the Society for Maternal-Fetal Medicine in February 2021 and those published by the Royal College of Obstetricians and Gynaecologists in the United Kingdom in June 2022. Several key differences exist in the clinical guidelines between the 2 organizations. With regard to the diagnosis of intrahepatic cholestasis of pregnancy, the Society for Maternal-Fetal Medicine considers any elevation in bile acids above the upper limit of normal in the setting of maternal pruritus diagnostic of intrahepatic cholestasis of pregnancy, whereas the Royal College of Obstetricians and Gynaecologists requires a pregnancy-specific elevated bile acid level of ≥19 mmol/L for diagnosis. Regarding the treatment of intrahepatic cholestasis of pregnancy, the Society for Maternal-Fetal Medicine recommends ursodeoxycholic acid as the first-line treatment of maternal symptoms. In contrast, the Royal College of Obstetricians and Gynaecologists specifically recommends against the routine use of ursodeoxycholic acid for intrahepatic cholestasis of pregnancy because of a lack of evidence regarding both maternal and fetal benefit. The Society for Maternal-Fetal Medicine recommends fetal surveillance at a gestational age when abnormal fetal testing would result in delivery being performed, whereas the Royal College of Obstetricians and Gynaecologists does not recommend any fetal testing beyond fetal kick count assessment. The Society for Maternal-Fetal Medicine recommends delivery at 36 to 39 weeks' gestation for intrahepatic cholestasis of pregnancy with bile acids <100 mmol/L and delivery at 36 weeks for bile acid levels >100 mmol/L. The Royal College of Obstetricians and Gynaecologists recommends serial assessment of bile acids with delivery timing stratified between 35- and 40-weeks' gestation according to bile acid levels.

Bile Acids in Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is the most common, reversible, and closely related to pregnancy condition characterized by elevated levels of bile acids (BAs) in blood serum and an increased risk of adverse perinatal outcomes. Due to the complex interactions between the mother and the fetus in metabolism and transplacental BAs transport, ICP is classified as a fetal-maternal disease. The disease is usually mild in pregnant women, but it can be fatal to the fetus, leading to numerous complications, including intrauterine death. The pathophysiology of the disease is based on inflammatory mechanisms caused by elevated BA levels. Although ICP cannot be completely prevented, its early diagnosis and prompt management significantly reduce the risk of fetal complications, the most serious of which is unexpected intrauterine death. It is worth emphasizing that all diagnostics and management of ICP during pregnancy are based on BA levels. Therefore, it is important to standardize the criteria for diagnosis, as well as recommendations for management depending on the level of BAs, which undoubtedly determines the impact on the fetus. The purpose of this review is to present the potential and importance of BAs in the detection and rules of medical procedure in ICP.

DIA-based proteomics analysis of serum-derived exosomal proteins as potential candidate biomarkers for intrahepatic cholestasis in pregnancy

BACKGROUND

Data-independent acquisition (DIA) is one of the most powerful and reproducible proteomic technologies for large-scale digital qualitative and quantitative research. The aim of this study was to use proteomic methodologies for the identification of biomarkers that are over or underexpressed in women with intrahepatic cholestasis of pregnancy (ICP) compared with controls and discover a potential biomarker panel for ICP detection.

METHODS

The participants included 11 ICP patients and 11 healthy pregnant women as controls. The clinical characteristic data and the laboratory biochemical data were collected at the time of recruitment. Then, a data-independent acquisition (DIA)-based proteomics approach was used to identify differentially expressed proteins (DEPs) in serum exosomes between ICP patients and controls. Finally, bioinformatics analysis was used to identify the relevant processes in which these DEPs were involved.

RESULTS

The proteomics results showed that there were 162 DEPs in serum exosomes between pregnant women with ICP and healthy pregnant women, of which 106 were upregulated and 56 were downregulated in ICP. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the identified proteins were functionally related to specific cell processes including apoptosis, lipid metabolism, immune response and cell proliferation, and metabolic disorders, suggesting that these may be primary causative factors in ICP pathogenesis. Meanwhile, complement and coagulation cascades may be closely related to the development of ICP. Receiver operating characteristic curve (ROC) analysis showed that the area under the curve values of Elongation factor 1-alpha 1, Beta-2-glycoprotein I, Zinc finger protein 238, CP protein and Ficolin-3 were all approximately 0.9, indicating the promising diagnostic value of these proteins.

CONCLUSIONS

This preliminary work provides a better understanding of the proteomic alterations in the serum exosomes of pregnant women with ICP.

Intrahepatic cholestasis of pregnancy - Time to redefine the reference range of total serum bile acids: A cross-sectional study

Objective

To establish pregnancy‐specific reference ranges for fasting and postprandial total serum bile acid (TSBA) concentrations.

Design

Cross‐sectional study.

Setting

Tertiary‐care university hospital.

Population

Healthy pregnant women at term admitted to the Obstetrics Department over a period of 1 year. Exclusion criteria were an established diagnosis of intrahepatic cholestasis of pregnancy (ICP) or any coexisting condition of increased risk for ICP.

Methods

Both fasting (after 8–14 h of fasting) and postprandial (2 h after meal) TSBA concentrations were measured in 612 women (with 528 fasting samples and 377 postprandial samples) by automated enzymatic spectrophotometric assay.

Main outcome measures

Fasting and postprandial TSBA concentrations in 612 women.

Results

Reference intervals of 4.4–14.1 μmol/L for fasting TSBA and 4.7–20.2 μmol/L for postprandial TSBA were established. The postprandial values were significantly higher than the fasting values, with a median increase of 1.0 μmol/L (p < 0.0001). A correlation between fasting TSBA concentrations and postprandial concentrations was found, as well as correlations with fetal sex, parity and assisted reproductive technologies. A seasonal pattern was noticed for both fasting and postprandial TSBA, with the highest values measured in the winter season (p < 0.01 and 0.02, respectively)

Conclusions

Normal pregnancy is associated with mild hypercholanaemia, and therefore a higher threshold should be considered for the diagnosis of ICP. We suggest using the upper reference limits observed in our healthy pregnant population (14 μmol/L for fasting TSBA and 20 μmol/L for postprandial TSBA). As the fasting measurement is more specific for the diagnosis, and the postprandial measurement is essential for the assessment of severity, it is recommended to measure both values rather than use random sampling.

Tweetable abstract

Normal pregnancy is associated with mild hypercholanaemia, a higher threshold should be considered for the diagnosis of ICP.

Normal pregnancy is associated with mild hypercholanaemia, a higher threshold should be considered for the diagnosis of ICP.

Linked article: This article is commented on by Ovadia et al., pp. 1897–1898. in this issue. To view this minicommentary visit https://doi.org/10.1111/1471‐0528.17171

Management of Intrahepatic Cholestasis of Pregnancy: Recommendations of the Working Group on Obstetrics and Prenatal Medicine - Section on Maternal Disorders

Intrahepatic cholestasis of pregnancy (ICP) is the most common liver disease specific to pregnancy. The cardinal symptom of pruritus and a concomitant elevated level of bile acids in the serum and/or alanine aminotransferase (ALT) are suggestive for the diagnosis. Overall, the maternal prognosis is good. The fetal outcome depends on the bile acid level. ICP is associated with increased risks for adverse perinatal outcomes, including preterm delivery, meconium-stained amniotic fluid, and stillbirth. Acute fetal asphyxia and not chronic uteroplacental dysfunction leads to stillbirth. Therefore, predictive fetal monitoring is not possible. While medication with ursodeoxycholic acid (UDCA) improves pruritus, it has not been shown to affect fetal outcome. The indication for induction of labour depends on bile acid levels and gestational age. There is a high risk of recurrence in subsequent pregnancies.

Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy is a common disorder of pregnancy manifested by pruritus and elevated bile acids. The etiology of cholestasis is poorly understood and management is difficult due to the paucity of data regarding its diagnosis, treatment, and related adverse outcomes. In this article, we review the epidemiology, pathophysiology, risk factors, laboratory findings, complications, treatment, management, and current evidence surrounding intrahepatic cholestasis of pregnancy.

[Intrahepatic cholestasis of pregnancy]

Intrahepatic cholestasis of pregnancy (ICP) is the most frequent pregnancy-specific liver disease. It is characterized by pruritus and an accompanying elevation of serum bile acid concentrations and/or alanine aminotransferase (ALT), which are the key parameters in the diagnosis. Despite good maternal prognosis, elevated bile acid concentration in maternal blood is an influencing factor to advers fetal outcome. The ICP is associated with increased rates of preterm birth, neonatal unit admission and stillbirth. This is the result of acute fetal asphyxia as opposed to a chronic uteroplacental insufficiency. Reliable monitoring or predictive tools (e.g. cardiotocography (CTG) or ultrasound) that help to prevent advers events are yet to be explored. Medicinal treatment with ursodeoxycholic acid (UDCA) does not demonstrably reduce adverse perinatal outcomes but does improve pruritus and liver function test results. Bile acid concentrations and gestational age should be used as indications to determine delivery. There is a high risk of recurrence in subsequent pregnancies.

Effect of Fasting on Total Bile Acid Levels in Pregnancy

OBJECTIVE

To evaluate differences between fasting and nonfasting bile acid levels in asymptomatic and symptomatic pregnant women.

METHODS

This is a report of two prospective cohort studies describing bile acid levels in the fasting and nonfasting state in pregnancy. The first cohort included asymptomatic women with singleton pregnancies. Women with a diagnosis of cholestasis, symptoms of cholestasis, or intolerance to components of a standardized meal were excluded. Bile acid levels were measured during the second and third trimesters after fasting and again 2 hours after a standardized meal. The second cohort included symptomatic women with singleton pregnancies in whom fasting and nonfasting bile acid levels were measured at the time of symptom evaluation. A cutoff of 10 micromoles/L was used for diagnosis.

RESULTS

A total of 27 women were included in the asymptomatic cohort. Median [interquartile range] fasting bile acid levels were significantly lower than nonfasting levels in both the second trimester (4.65 micromoles/L [1.02-29.57] vs 13.62 micromoles/L [2.03-40.26]; P<.001) and third trimester (8.31 micromoles/L [1.14-51.26] vs 17.35 micromoles/L [1.77-62.93]; P<.001). Bile acid levels exceeded 10 micromoles/L in 21% of the fasting samples and in 58% of the nonfasting samples in the third trimester. A total of 26 women were included in the symptomatic cohort. Median [interquartile range] fasting bile acid levels were significantly lower than nonfasting values (11.5 micromoles/L [7-56] vs 13.5 micromoles/L [9-142]; P<.001). Six patients in the symptomatic cohort (23%) had nonfasting bile acid levels greater than 10 micromoles/L that dropped below 10 micromoles/L when fasting.

CONCLUSION

Fasting bile acid levels are significantly lower when compared with nonfasting values in both asymptomatic and symptomatic pregnant women. In asymptomatic women, nonfasting bile acid levels often exceeded 10 micromoles/L whereas fasting values did not. In symptomatic women, fasting bile acid levels resulted in 23% fewer diagnoses of cholestasis when compared with nonfasting values. These findings suggest that fasting evaluation of bile acid levels or a higher threshold for diagnosis of cholestasis should be considered.

Society for Maternal-Fetal Medicine Consult Series #53: Intrahepatic cholestasis of pregnancy: Replaces Consult #13, April 2011

Intrahepatic cholestasis of pregnancy is a hepatic disorder characterized by pruritus and an elevation in serum bile acid levels. Although intrahepatic cholestasis of pregnancy poses little risk for women, this condition carries a significant risk for the fetus, including complications such as preterm delivery, meconium-stained amniotic fluid, and stillbirth. The purpose of this Consult is to review the current literature on intrahepatic cholestasis of pregnancy and provide recommendations based on the available evidence. The recommendations by the Society for Maternal-Fetal Medicine are as follows: (1) we recommend measurement of serum bile acid and liver transaminase levels in patients with suspected intrahepatic cholestasis of pregnancy (GRADE 1B); (2) we recommend that ursodeoxycholic acid be used as the first-line agent for the treatment of maternal symptoms of intrahepatic cholestasis of pregnancy (GRADE 1A); (3) we suggest that patients with a diagnosis of intrahepatic cholestasis of pregnancy begin antenatal fetal surveillance at a gestational age when delivery would be performed in response to abnormal fetal testing results or at the time of diagnosis if the diagnosis is made later in gestation (GRADE 2C); (4) we recommend that patients with total bile acid levels of ≥100 μmol/L be offered delivery at 36 0/7 weeks of gestation, given that the risk of stillbirth increases substantially around this gestational age (GRADE 1B); (5) we recommend delivery between 36 0/7 and 39 0/7 weeks of gestation for patients with intrahepatic cholestasis of pregnancy and total bile acid levels of <100 μmol/L (GRADE 1C); (6) we recommend administration of antenatal corticosteroids for fetal lung maturity for patients delivering before 37 0/7 weeks of gestation if not previously administered (GRADE 1A); (7) we recommend against preterm delivery at <37 weeks of gestation in patients with a clinical diagnosis of intrahepatic cholestasis of pregnancy without laboratory confirmation of elevated bile acid levels (GRADE 1B).