Fetal outcomes in pregnancies complicated by intrahepatic cholestasis of pregnancy in a Northern California cohort

Proteomic Biomarkers of Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease, which can lead to adverse fetal outcomes, including preterm labor and intrauterine death. The pathogenesis of ICP is still unclear. We hypothesized that pathological index leads to abnormal placenta changes in ICP. Investigation of these differences in protein expression in parallel profiling is essential to understand the comprehensive pathophysiological mechanism underlying ICP. The present study screened differentially expressed proteins (DEPs) as novel diagnostic markers for ICP. Proteomic profiles of placental tissues from 32 ICP patients and 24 healthy volunteers (controls) were analyzed. Our founding was valid by following western blotting and immunohistochemistry staining, respectively. The association of the key protein expression with clinicopathological features of ICP was further analyzed. A total of 178 DEPs were identified between the ICP and control groups. Functional enrichment analysis showed these proteins were significantly enriched in the PPAR singling pathway by KEGG and PPARα/RXRα activation by IPA. Apolipoprotein A2 (APOA2) was the only upregulated protein, which uniquely identified in ICP groups and related to both pathways. Validation of western blotting and immunohistochemical staining analysis showed significantly higher APOA2 expression in the ICP group than in the control group. Furthermore, the expression of APOA2 is associated with clinicopathological features in ICP groups. Receiver operating characteristic (ROC) curve analyses showed that the AUC of APOA2 was 0.8984 (95% confidence interval (CI): 0.772-1.000). This study has identified up-regulated APOA2 associated with PPAR singling pathway and PPARα/RXRα activation in ICP. Thus, APOA2 may be involved in ICP pathogenesis, serving as a novel biomarker for its diagnosis.

Gradual dosing of ursodeoxycholic acid in mothers with intrahepatic cholestasis of pregnancy may improve composite neonatal outcome

INTRODUCTION AND OBJECTIVES

Intrahepatic cholestasis of pregnancy (ICP) is often accompanied by fetal and maternal complications.

MATERIALS AND METHODS

Retrospective review of the clinical course of women with ICP and their neonates treated at our medical center over a 10-year period. Special attention was paid to the maternal and neonatal response to 2 different modes of ursodeoxycholic acid (UDCA) administration.

RESULTS

Neonates of mothers with high total bile acid levels had a poorer composite neonatal outcome. Twenty-seven women who presented at an advanced stage of their pregnancies did not receive UDCA. UDCA was administered in 2 modes: either a full dose at admission (76 women) or a gradually increasing dose until the desired dosage was reached (25 women). The mean gestational age at delivery for the 94 neonates that were exposed to full UDCA dose was the lowest (36±2.3 weeks for the full dose, 37±1.4 weeks for the 30 neonates from the gradually increasing dose, 38±1.6 weeks for the 29 neonates from the no treatment group, p<0.001). The group of neonates that were exposed to full UDCA dose had the highest rate of unfavorable composite neonatal outcome (53% for full dose, 30% for gradually increasing dose, 24% for the no treatment group, p=0.006).

CONCLUSIONS

Compared to the administration of a full UDCA dose, the administration of a gradually increasing dose of UDCA may be associated with a greater gestational age at delivery and fewer events of unfavorable composite neonatal outcomes. These novel findings should be retested prospectively in a large cohort of patients.

COVID-stasis of Pregnancy: An Increased Prevalence of COVID-19 in Patients with Cholestasis

OBJECTIVE

 To evaluate the relationship between intrahepatic cholestasis of pregnancy (ICP) and coronavirus disease 2019 (COVID-19).

STUDY DESIGN

 We performed a retrospective cohort study of pregnant women undergoing induction of labor (IOL) at a single institution between May 2020 to January 2021. Primary exposure was diagnosis of intrahepatic cholestasis of pregnancy (ICP). The primary outcome was the prevalence of COVID-19 as determined by reverse-transcriptase polymerase chain reaction testing on nasopharyngeal swabs for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) on routine admission testing. Secondary outcomes were abnormal laboratory values and adverse fetal outcomes. Logistic regression with log link analysis was performed comparing patients undergoing IOL for ICP compared with IOL for all other indications. The moderating effect of ethnicity was assessed by the interaction between ethnicity and ICP in a logistic regression model. The Wilcoxon rank-sum test and Fisher's exact test were performed for the secondary outcome analyses.

RESULTS

 Over the course of the study, 596 patients underwent IOL: 24 for ICP and 572 for other indications. The overall prevalence of COVID-19 positivity in the cohort was 5.5% (33 of 596). Those with ICP were more likely to test positive for COVID-19 compared with those with other IOL indications (29.2 vs. 4.5%, RR = 6.4, 95% CI: 2.8-12.5, p < 0.001). All patients with ICP who tested positive for COVID-19 were Hispanic. To analyze the moderating effect of ethnicity, the results of the logistic model found the interaction between ethnicity and ICP to not be significant (p = 0.991). In patients with ICP, the median AST (aspartate aminotransferase) was higher than those with COVID-19 (p = 0.0182). There were no adverse fetal outcomes in the ICP group.

CONCLUSION

 In this single-site retrospective cohort study, we demonstrated an increased prevalence of COVID-19 in those with ICP in general and among Hispanic patients specifically. Despite this difference, there was no increased risk of adverse fetal outcomes.

KEY POINTS

· There is an increased prevalence of COVID-19 among Hispanic patients with ICP.. · The median AST of COVID-19-positive patients was significantly higher than COVID-19-negative patients.. · There was no increased risk of adverse fetal outcomes in with COVID-19 and ICP..

Evaluation of maternal serum vascular endothelial growth factor C and D levels in intrahepatic cholestasis of pregnancy

OBJECTIVE

This study aimed to investigate maternal serum vascular endothelial growth factor (VEGF) C and D levels in patients with intrahepatic cholestasis of pregnancy (ICP).

METHODS

A total of 83 patients, including 41 patients with ICP and 42 healthy pregnant women, were included in the study. We first compared the maternal serum VEGF-C and VEGF-D levels between the ICP and control groups and then examined the correlation between the serum VEGF-C level and the bile acid level in patients with severe ICP.

RESULTS

We observed statistically significantly higher serum VEGF-C levels and lower VEGF-D levels in the ICP group compared with the healthy controls (P < 0.001 and P = 0.015, respectively). According to receiver operating characteristic analysis, the optimal cutoff value for ICP was 147 ng/mL in the determination of the VEGF-C level (specificity and sensitivity: 76%). In patients with severe ICP, the serum VEGF-C statistically significantly correlated with the bile acid level (P = 0.019).

CONCLUSION

This study showed that the maternal serum VEGF-C level was higher and the VEGF-D level was lower in patients with ICP compared with healthy pregnant women. We also found that the VEGF-C level was correlated with the serum bile acid level in patients with severe ICP. Serum VEGF-C level can be used in the diagnosis and follow-up of intrahepatic pregnancy cholestasis.

A Chinese longitudinal maternity cohort study (2013-2021) on intrahepatic cholestasis phenotypes: Risk associations from environmental exposure to adverse pregnancy outcomes

Intrahepatic cholestasis of pregnancy (ICP) is an idiopathic disease that occurs during mid-to-late pregnancy and is associated with various adverse pregnancy outcomes, including intrauterine fetal demise. However, since the underlying cause of ICP remains unclear, there is an ongoing debate on the phenotyping criteria used in the diagnostic process. Here, we identified single- and multi-symptomatic ICP (ICP-S and ICP-M) in 104,221 Chinese females from the ZEBRA maternity cohort, with the objective of exploring the risk implications of the two phenotypes on pregnancy outcomes and from environmental exposures. We employed multivariate binary logistic regression to estimate confounder-adjusted odds ratios and found that ICP-M was more strongly associated with preterm birth and low birth weight compared to ICP-S. Throughout pregnancy, incremental exposure to PM2.5, O3, and greenness could alter ICP risks by 17.3%, 12.5%, and -2.3%, respectively, with more substantial associations observed with ICP-M than with ICP-S. The major scientific advancements lie in the elucidation of synergistic risk interactions between pollutants and the protective antagonistic effects of greenness, as well as highlighting the risk impact of preconceptional environmental exposures. Our study, conducted in the context of the "three-child policy" in China, provides epidemiological evidence for policy-making to safeguard maternal and neonatal health.

Predictors of Adverse Fetal Outcomes in Intrahepatic Cholestasis of Pregnancy (ICP): a Narrative Review

Intrahepatic cholestasis of pregnancy (ICP) is a hepatic disorder in pregnancy linked with adverse fetal outcomes, which primarily manifests in the late second and third trimesters of pregnancy. This review aims to recapitulate the existing evidence on factors that can predict detrimental perinatal outcomes in pregnant women diagnosed with intrahepatic cholestasis of pregnancy. We searched PubMed, Web of Science, Cochrane Library, Scopus, Medline, and Embase databases and selected studies related to predictors of fetal outcome in intrahepatic cholestasis of pregnancy. Studies of the articles showed that predictors of an adverse fetal outcome include in vitro fertilization (IVF) pregnancy, multifetal pregnancy, biochemical markers, gestational age of ICP onset, presence of comorbidities (preeclampsia and gestational diabetes mellitus), maternal history of ICP, and hepatobiliary disease.Intrahepatic cholestasis of pregnancy (ICP) complicates the pregnancy. Hence, early assessment of low-risk and high-risk groups will help to administer definite management protocols and strategies to prevent adverse neonatal outcomes. Further research should concentrate on the number of conditions/factors and the predictive power of different factors to determine the most reliable predictors and biomarkers that can predict adverse fetal outcomes and improve the assessment of risk in pregnancy complicated with ICP.

Pregnancy outcomes following antenatal screening for intrahepatic cholestasis of pregnancy (ICP)

OBJECTIVE

To evaluate the maternal and perinatal outcomes following antenatal screening for ICP using a retrospective approach.

MATERIALS AND METHODS

A retrospective study was conducted at the second affiliated hospital of Chongqing Medical University, Chongqing, China, from 2012 to 2017. Pregnant women registered for antenatal in our hospital were screened for ICP. The pregnant women with detailed delivery record and presenting with the diagnosis of ICP based on TBA level ≥10 mmol/L and abnormal liver enzymes were included in the study.

METHOD

The pregnant women with detailed delivery records presenting with the diagnosis of ICP based on TBA level ≥10 mmol/L and abnormal liver enzymes were included in the study. 1410 pregnant women were enrolled in this study. We selected 940 pregnant women without the diagnosis of ICP as our control and 470 pregnant women diagnosed with ICP as our case study. Data collection and sampling in the control group was done using microsoft excel (version 16.61) random number generator.

RESULTS

The mean age of the pregnant women and the gestational age at the time of diagnosis of ICP were 29.01 ± 4.3 years and 31.90 ± 8.83 weeks, respectively. It was found that a significant number of patients with ICP had a preterm birth and low birth weight (LBW), n = 151 (32.5%) P < 0.001 and n = 70 (14.9%) P < 0.001, respectively. A significant number of patients in the case group had a history of liver disease and gall bladder disease, p < 0.001 and p = 0.005, respectively, and a higher rate of GDM p < 0.001. Despite treatment, high TBA titer among ICP patients was associated with preterm delivery.

CONCLUSION

ICP in pregnancy leads to complications and poor perinatal outcomes. Fetal outcomes depend on the TBA levels; therefore, early diagnosis of ICP through routine screening followed by treatment is recommended in high-risk persons/areas.

Risk factors associated with cesarean section and adverse fetal outcomes in intrahepatic cholestasis of pregnancy

Background

To determine the risk factors for cesarean section (CS) and adverse fetal outcomes (AFOs) in patients with intrahepatic cholestasis of pregnancy (ICP) based on the severity of maternal hypercholanemia.

Methods

A hospital-based retrospective cohort study was performed between January 1, 2015, and December 31, 2019. A total of 227 nulliparous women with a singleton fetus complicated by ICP were included. The patients were divided into two groups according to the levels of total bile acids, that is, mild (10 μmol/L < total bile acids < 40 μmol/L) and severe (≥40 μmol/L). The patients' clinical characteristics and fetal outcomes were assessed.

Results

Among the 227 eligible women, 177 (78.0%) were allocated to the mild group and 50 (22.0%) were in the severe group. Women with severe ICP also had a significantly higher incidence of planned and unplanned CS compared with mild ICP subjects (52.0% vs. 23.7% and 22.0% vs. 6.8%, respectively; p < 0.001). The indications for CS showed that fetal intolerance (65.4% vs. 14.3%) was higher in severe ICP compared with mild ICP (p < 0.001). Severe ICP was associated with an increased risk of preterm delivery (p < 0.001), low birthweight (p = 0.001), and neonatal intensive care unit (NICU) admission (p < 0.001). Women with severe ICP (OR 6.397, 95%CI 3.041-13.455, p < 0.001) or preeclampsia (OR 12.434, 95%CI 5.166-29.928, p < 0.001) had increased risks of AFOs compared to controls.

Conclusions

Severe ICP and preeclampsia are associated with a higher incidence of AFOs.

SWATH proteomics analysis of placental tissue with intrahepatic cholestasis of pregnancy

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) usually occurs in the second and third trimesters. The disease's etiology and diagnostic criteria are currently unknown. Based on a sequence window to obtain all theoretical fragment ions (SWATH) proteomic approach, this study sought to identify potential proteins in placental tissue that may be involved in the pathogenesis of ICP and adverse fetal pregnancy outcomes.

METHODS

The postpartum placental tissue of pregnant women with ICP were chosen as the case group (ICP group) (subdivided into mild ICP group (MICP group) and severe ICP group (SICP group)), and healthy pregnant women were chosen as the control group (CTR). The hematoxylin-eosin (HE) staining was used to observe the histologic changes of placenta. The SWATH analysis combined with liquid chromatography-tandem mass spectrometry (LC-MS) was used to screen the differentially expressed proteins (DEPs) in ICP and CTR groups, and bioinformatics analysis was used to find out the biological process of these differential proteins.

RESULTS

Proteomic studies showed there were 126 DEPs from pregnant women with ICP and healthy pregnant women. Most of the identified proteins were functionally related to humoral immune response, cell response to lipopolysaccharide, antioxidant activity and heme metabolism. A subsequent examination of placentas from patients with mild and severe ICP revealed 48 proteins that were differentially expressed. Through death domain receptors and fibrinogen complexes, these DEPs primarily regulate extrinsic apoptotic signaling pathways, blood coagulation, and fibrin clot formation. The differential expressions of HBD, HPX, PDE3A, and PRG4 were down-regulated by Western blot analysis, which was consistent with proteomics.

DISCUSSION

This preliminary study helps us to understand the changes in the placental proteome of ICP patients, and provides new insights into the pathophysiology of ICP.

Intrahepatic cholestasis of pregnancy: from an obstetrician point of view

Intrahepatic cholestasis of pregnancy (ICP) is the commonest among the specific dermatoses of pregnancy. The disease is characterised by intense pruritus and specifically by elevated bile acid levels and owing to the rarity of data published in this context, the disease carries a great challenge in both diagnosis and management. The disease is associated with significant maternal as well as perinatal adverse effects, hence, this article aims at improving the knowledge of the women's health carers with the up-to-date and evidence-based, whenever possible, recommendations while managing patients with ICP.

Application of metabolomics in intrahepatic cholestasis of pregnancy: a systematic review

Background

Intrahepatic cholestasis of pregnancy (ICP) is a severe idiopathic disorder of bile metabolism; however, the etiology and pathogenesis of ICP remain unclear.

Aims

This study comprehensively reviewed metabolomics studies related to ICP, to help in identifying the pathophysiological changes of ICP and evaluating the potential application of metabolomics in its diagnosis.

Methods

Relevant articles were searched through 2 online databases (PubMed and Web of Science) from January 2000 to March 2022. The metabolites involved were systematically examined and compared. Pathway analysis was conducted through the online software MetaboAnalyst 5.0.

Results

A total of 14 papers reporting 212 metabolites were included in this study. There were several highly reported metabolites: bile acids, such as glycocholic acid, taurochenodeoxycholic acid, taurocholic acid, tauroursodeoxycholic acid, and glycochenodeoxycholic acid. Dysregulation of metabolic pathways involved bile acid metabolism and lipid metabolism. Metabolites related to lipid metabolism include phosphatidylcholine, phosphorylcholine, phosphatidylserine, sphingomyelin, and ceramide.

Conclusions

This study provides a systematic review of metabolomics of ICP and deepens our understanding of the etiology of ICP.

Whole-exome sequencing expands the roles of novel mutations of organic anion transporting polypeptide, ATP-binding cassette transporter, and receptor genes in intrahepatic cholestasis of pregnancy

Background: Intrahepatic cholestasis of pregnancy (ICP) is associated with a high incidence of fetal morbidity and mortality. Therefore, revealing the mechanisms involved in ICP and its association with fetal complications is very important.

Methods: Here, we used a whole-exome sequencing (WES) approach to detect novel mutations of organic anion transporting polypeptide (OTAP) genes, ATP-binding cassette transporter (ABC) genes, and receptor genes associated with ICP in 249 individuals and 1,029 local control individuals. Two available tools, SIFT and PolyPhen-2, were used to predict protein damage. Protein structuremodeling and comparison between the reference and modified protein structures were conducted by SWISS-MODEL and Chimera 1.14rc software, respectively.

Results: A total of 5,583 mutations were identified in 82 genes related to bile acid transporters and receptors, of which 62 were novel mutations. These novel mutations were absent in the 1,029 control individuals and three databases, including the 1,000 Genome Project (1000G_ALL), Exome Aggregation Consortium (ExAC), and Single-Nucleotide Polymorphism Database (dbSNP). We classified the 62 novel loci into two groups (damaging and probably damaging) according to the results of SIFT and PolyPhen-2. Out of the 62 novel mutations, 24 were detected in the damaging group. Of these, five novel possibly pathogenic variants were identified that were located in known functional genes, including ABCB4 (Ile377Asn), ABCB11 (Ala588Pro), ABCC2 (Ile681Lys and Met688Thr), and NR1H4 (Tyr149Ter). Moreover, compared to the wild-type protein structure, ABCC2 Ile681Lys and Met688Thr protein structures showed a slight change in the chemical bond lengths of ATP-ligand binding amino acid side chains. The combined 32 clinical data points indicate that the mutation group had a significantly (p = 0.04) lower level of Cl ions than the wild-type group. Particularly, patients with the 24 novel mutations had higher average values of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bile acids (TBA), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) than patients with the 38 novel mutations in the probably damaging group and the local control individuals.

Conclusion: The present study provides new insights into the genetic architecture of ICP involving these novel mutations.

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 Increases Inflammatory Susceptibility in Neonatal Offspring by Modulating Gut Microbiota

Intrahepatic cholestasis of pregnancy (ICP) is a liver disease of pregnancy that is characterized by increased bile acid levels in maternal serum. Studies have shown that cholestatic pregnancy can result in long-term metabolic disturbances in the offspring. However, how ICP shapes the offspring’s immunity and predisposition to inflammatory disorders at an early stage is unknown. In this study, we investigated the effect of maternal cholestasis on neonatal offspring metabolism and immune function. We compared 71 neonates with ICP mothers and 63 neonates with healthy mothers and found that the incidence of jaundice and infection was significantly higher in ICP offspring. Maternal serum total bile acid level was associated with blood cell counts in full-term ICP offspring. In animal experiments, a compensatory activation of hepatic and ileal farnesoid X receptor (FXR) and altered gut microbiota in the first week were found in ICP offspring. We also investigated lipopolysaccharide (LPS)-induced inflammatory responses in neonatal rats and found that ICP offspring were more susceptible to inflammation. To understand the correlation between congenital abnormal FXR activation and tissue immunity dysregulation, we assessed the effects of the FXR agonist GW4064 and FXR antagonist E/Z-GS in ICP offspring after LPS exposure. The expression of several pro-inflammatory cytokines significantly decreased after treatment with E/Z-GS but increased after treatment with GW4064. Treatment with the probiotic Lactobacillus rhamnosus LRX01 that inhibits FXR expression in the ileum reduced susceptibility to LPS exposure in ICP offspring. The current study indicated that cholestatic pregnancy may increase the susceptibility of the offspring to inflammation by altering bile acid metabolism and gut microbiota at an early stage. We suggest that supplementation with Lactobacillus rhamnosus LRX01, which inhibits FXR expression in the ileum, may improve intestinal immunity in ICP offspring.

Identification of two novel pathogenic variants of the NR1H4 gene in intrahepatic cholestasis of pregnancy patients

Background

Intrahepatic cholestasis of pregnancy (ICP) can cause adverse pregnancy outcomes, such as spontaneous preterm delivery and stillbirth. It is a complex disease influenced by multiple factors, including genetics and the environment. Previous studies have reported that functioning nuclear receptor subfamily 1 group H member 4 (NR1H4) plays an essential role in bile acid (BA) homeostasis. However, some novel variants and their pathogenesis have not been fully elucidated. Therefore, this research aimed to investigate the genetic characteristics of the NR1H4 gene in ICP.

Methods

In this study, we sequenced the entire coding region of NR1H4 in 197 pregnant women with ICP disease. SIFT and PolyPhen2 were used to predict protein changes. Protein structure modelling and comparisons between NR1H4 reference and modified protein structures were performed by SWISS-MODEL and Chimera 1.14rc, respectively. T-tests were used to analyse the potential significant differences between NR1H4 mutations and wild types for 29 clinical features. Fisher’s test was conducted to test the significance of differences in mutation frequencies between ICP and the three databases.

Results

We identified four mutations: two novel missense mutations, p.S145F and p.M185L; rs180957965 (A230S); and rs147030757 (N275N). The two novel missense mutations were absent in 1029 controls and three databases, including the 1000 Genomes Project (1000G_ALL), Exome Aggregation Consortium (ExAC) and ChinaMAP. Two web-available tools, SIFT and PolyPhen2, predicted that these mutations are harmful to the function of the protein. Moreover, compared to the wild-type protein structure, the NR1H4 p.S145F and p.M185L protein structure showed a slight change in the chemical bond in two zinc finger structures. Combined clinical data indicate that the mutation group had higher levels of total bile acid (TBA) than the wild-type group. Therefore, we hypothesized that these two mutations altered the protein structure of NR1H4, which impaired the function of NR1H4 itself and its target gene and caused an increase in TBA.

Conclusions

To our knowledge, this is the first study to identify the novel p.S145F and p.M185L mutations in 197 ICP patients. Our present study provides new insights into the genetic architecture of ICP involving the two novel NR1H4 mutations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01240-w.

Studies on Novel Diagnostic and Predictive Biomarkers of Intrahepatic Cholestasis of Pregnancy Through Metabolomics and Proteomics

Background

Intrahepatic cholestasis of pregnancy (ICP) usually occurs in the third trimester and is associated with increased risks in fetal complications. Currently, the exact mechanism of this disease is unknown. The purpose of this study was to develop potential biomarkers for the diagnosis and prediction of ICP.

Methods

We enrolled 40 pregnant women diagnosed with ICP and 40 healthy pregnant controls. The number of placental samples and serum samples between the two groups was 10 and 40 respectively. Ultra-performance liquid chromatography tandem high-resolution mass spectrometry was used to analyze placental metabolomics. Then, we verified the differentially expressed proteins and metabolites, both placental and blood serum, in the first, second, and third trimesters.

Results

Metabolomic analysis of placental tissue revealed that fatty acid metabolism and primary bile acid biosynthesis were enriched. In the integrated proteomic and metabolomic analysis of placental tissue, peroxisomal acyl-CoA oxidase 1 (ACOX1), L-palmitoylcarnitine, and glycocholic acid were found to be three potential biomarkers. In a follow–up analysis, expression levels of both placental and serum ACOX1, L-palmitoylcarnitine, and glycocholic acid in both placenta and serum were found to be significantly higher in third-trimester ICP patients; the areas under the ROC curves were 0.823, 0.896, and 0.985, respectively. Expression levels of serum ACOX1, L-palmitoylcarnitine, and glycocholic acid were also significantly higher in first- and second-trimester ICP patients; the areas under the ROC curves were 0.726, 0.657, and 0.686 in the first trimester and 0.718, 0.727, and 0.670 in the second trimester, respectively. Together, levels of the three aforementioned biomarkers increased the value for diagnosing and predicting ICP (AUC: 0.993 for the third, 0.891 for the second, and 0.932 for the first trimesters).

Conclusions

L-palmitoylcarnitine, ACOX1, and glycocholic acid levels taken together may serve as a new biomarker set for the diagnosis and prediction of ICP.

Alpha-1 Antitrypsin Z Variant (AAT PI*Z) as a Risk Factor for Intrahepatic Cholestasis of Pregnancy

Background: Intrahepatic cholestasis of pregnancy (ICP; prevalence 0.2–15.6%) is the most common pregnancy-related liver disorder. It may have serious consequences for a pregnancy, including increased risk of preterm delivery, meconium staining of amniotic fluid, fetal bradycardia, distress, and fetal demise. In cases of high bile acids (>100μmol/L), patients have 10-fold increase in the risk of stillbirth. Biophysical methods of fetal monitoring, such as cardiotocography, ultrasonography, or Doppler have been proven unreliable for risk prediction in the course of intrahepatic cholestasis. Therefore, we believe extensive research for more specific, especially early, markers should be carried out. By analogy with cholestasis in children with inherited alpha-1 antitrypsin deficiency (AATD), we hypothesized the SERPINA1 Z pathogenic variant might be related to a higher risk of cholestasis in pregnancy. This study aimed to investigate the most common AATD variants (Z and S SERPINA1 alleles) in a group of cholestatic pregnant women.

Results: The Z carrier frequency was calculated to be 6.8%, which is much higher compared to the general population [2.3%; the Chi-squared test with Yates correction is 6.8774 (p=0.008)].

Conclusion: Increased prevalence of SERPINA1 PI*Z variant in a group of women with intrahepatic cholestasis may suggest a possible genetic origin of a higher risk of intrahepatic cholestasis in pregnancy.

From Pruritus to Cholestasis: Building a Statistical Model and Online Application to Predict a Diagnosis Prior to Bile Acid Determination

OBJECTIVE

This study aimed to create a statistical model using clinical and laboratory parameters to predict which patients presenting with pruritus in pregnancy will have elevated total bile acids (TBA) and thus, have a high risk of intrahepatic cholestasis of pregnancy (ICP).

STUDY DESIGN

Retrospective cohort study of patients presenting with pruritus in pregnancy and had TBA sent from a single public hospital from January 1, 2017, to December 31, 2017. Primary outcome is TBA ≥ 10 µmol/L. Multivariate logistic regression with stepwise and backward variable selection were used to create predictive models. Four models were compared using Akaike information criterion (AIC), C-statistic, and the DeLong nonparametric approach to test for differences between area under the curve (AUC) of receiver operating characteristic (ROC) curves. Internal validation was performed via fivefold cross-validation technique on the best-fitting, most parsimonious model.

RESULTS

Of the 320 patients with pruritus, 153 (47.8%) had elevated bile acid levels ≥10 µmol/L. Sixty-nine variables were assessed for association with the primary outcome. Five variables were significantly associated with elevated TBA: pruritus of palms and soles (adjusted odds ratio [aOR]: 2.35 [95% confidence interval, CI: 1.22, 4.54]), gestational hypertension (aOR: 0.10 [95% CI: 0.02, 0.60]), log of total bilirubin (aOR: 4.71 [95% CI: 2.28, 9.75]), systolic blood pressure (aOR: 0.97 [95% CI: 0.94, 0.99]), and alanine aminotransferase (aOR: 1.05 [95% CI: 1.02, 1.07]). The final model was chosen for being parsimonious while having the lowest AIC with highest AUC (0.85; 95% CI: 0.81, 0.89). Internal validation using a probability threshold of 50% demonstrated a sensitivity of 65.5%, specificity of 83.5%, and accuracy of 75.1%.

CONCLUSION

We provide a predictive model using five simple variables to determine the probability that a patient presenting with pruritus in pregnancy carries the diagnosis of ICP. This tool, available via a web app, is designed to aid providers and enhance clinical judgment in difficult triage situations.

KEY POINTS

· Currently, no standard method to triage pruritus in pregnancy exists.. · We present a predictive statistical model using five readily available clinical variables.. · Final calculator yields probability of having intrahepatic cholestasis of pregnancy..

Cholestasis: A Prospective Study of Perinatal Outcomes and Time to Symptom Improvement

OBJECTIVE

Although intrahepatic cholestasis of pregnancy (ICP) remains poorly understood, there are several perinatal complications associated with this condition. This study aimed to examine perinatal outcomes of women with ICP, evaluate outcomes according to severity of disease, and monitor time to symptom improvement following diagnosis.

STUDY DESIGN

It involves a prospective, observational study of women with ICP at a single institution. Women with new-onset pruritus without rash were referred to a high-risk obstetrics clinic and evaluated with fasting total bile acids (TBA). Laboratory-confirmed ICP was defined as fasting TBA ≥10 µmol/L. Following diagnosis, a standardized protocol was utilized, including treatment with ursodeoxycholic acid (UDCA). Perinatal outcomes were compared amongst those with and without ICP, and to the general population. Women with ICP were further analyzed based on maximum TBA: 10 to 39, 40 to 99, and ≥100 µmol/L. A Kaplan-Meier survival curve was used to analyze time to symptom improvement.

RESULTS

A total of 404 patients were evaluated and 212 (52%) were diagnosed with ICP. The mean gestational age at diagnosis was 34.1 ± 3.3 weeks. When comparing those with ICP to those not confirmed, and to the general population, there were no differences in age, parity, mode of delivery, preeclampsia, or stillbirth (p > 0.05). Preterm birth was significantly associated with ICP (p < 0.01). This relationship was significant across increasing severity of TBA (p < 0.01) and persisted when examining rates of spontaneous preterm birth (p < 0.01). All women with fasting TBA ≥40 µmol/L delivered preterm due to premature rupture of membranes or spontaneous labor. Time to symptom improvement after diagnosis was over 2 weeks on average; however, this time increased with worsening severity of disease.

CONCLUSION

Despite treatment with UDCA, women with ICP are at increased risk for spontaneous preterm birth, and this risk significantly increased with severity of disease. Although not significant, a trend exists between increasing time to symptom improvement and worsening severity of disease.

KEY POINTS

· Preterm birth is significantly increased in patients diagnosed with intrahepatic cholestasis of pregnancy.. · The risk of preterm birth in women with ICP increases across increasing strata of disease.. · Following initiation of treatment in patients with ICP, symptom improvement takes more than 2 weeks..

Intrahepatic Cholestasis of Pregnancy and Associated Adverse Maternal and Fetal Outcomes: A Retrospective Case-Control Study

Objective

Intrahepatic cholestasis of pregnancy (ICP) is a common pregnancy-related liver disease and is associated with an increased risk of adverse neonatal outcomes. Ursodeoxycholic acid (UDCA) is the most effective treatment. This study was aimed at investigating the adverse outcomes of ICP and evaluating the effects of treatment with UDCA in patients with ICP.

Methods

We included 114 women with ICP and 3725 women without ICP (no-ICP group) who delivered in our hospital between September 2017 and August 2019. The prevalence of ICP in this study was 3.15%. We matched each woman with ICP to five controls. Of all the 114 women with ICP, 73 (64.04%) received UDCA while 41 (35.96%) did not. Logistic multivariate regression analysis was used to compare the adverse outcomes between those with ICP and matched controls as well as between those who received UDCA (UDCA group) and those who did not (non-UDCA group).

Results

Compared with controls, women with ICP were more likely to have preeclampsia (adjusted odds ratio, aOR = 16.74, 95% CI 5.29-52.98), cesarean section (aOR = 1.76, 95% CI 1.10-2.81), and preterm birth (aOR = 24.35, 95% CI 2.74-216.67). Administration of UDCA reduced the rate of preterm birth (1.37% vs. 14.63%, aOR = 0.10, 95% CI 0.01-0.90).

Conclusion

ICP increased the risk of preeclampsia, cesarean section, and preterm birth. UDCA could reduce the rate of preterm birth.

Maternal and Fetal Outcome in Intrahepatic Cholestasis of Pregnancy in a Multicultural Society Conducted at a Tertiary Care Hospital in Dubai

<b><i>Introduction:</i></b> Intrahepatic cholestasis of pregnancy (ICP) has been sparsely studied especially in the Middle East. The incidence and outcome of ICP varies worldwide. Its incidence in the Middle East and primary maternal and fetal outcome must be evaluated to ascertain the burden so that appropriate preventive and intervention measures can be formulated and implemented. <b><i>Objective:</i></b> To assess the incidence, associations, and maternal-fetal outcomes in ICP. <b><i>Design:</i></b> Case-control study. Settings: tertiary care hospital settings affiliated with the academic center in the UAE. Patients and methods: a total of 150 patients were included from October 2016 to September 2018 in the study with 75 cases of ICP and 75 controls matched according to age and date of delivery. The maternal risk factors attributable to ICP were recorded. Biochemical profile of mothers was monitored. Maternal and fetal outcomes were compared in 2 groups. Main outcomes measured: incidence and associations of ICP were evaluated. Maternal and fetal outcomes were compared in cases and controls. Sample size: 150. <b><i>Result:</i></b> The incidence of ICP in our study in the UAE was 1.0%. ICP has significant association with past obstetric cholestasis history (<i>p</i> value &#x3c;0.01, odds ratio [OR] 9.3, 95% CI: 2.1–41.8), gestational diabetes (<i>p</i> value &#x3c;0.05, OR 2.0, 95% CI: 1.0–3.8), pre-eclampsia (<i>p</i> value &#x3c;0.05, OR 7.2, 95% CI: 1.6–33.1), and undergoing induction of labor (<i>p</i> value &#x3c;0.01, OR 8.1, 95% CI: 3.7–17.8). The maternal bile acid level above 40 μmol/L is ­associated with higher chances of preterm delivery (<i>p</i> value &#x3c;0.01, OR 8.2, 95% CI: 3.0–22.5), intrauterine fetal demise (<i>p</i> value &#x3c;0.01), low birth weight (<i>p</i> value &#x3c;0.01, OR 13.6, 95% CI: 4.2–43.5), respiratory distress (<i>p</i> value &#x3c;0.05, OR 15.5, 95% CI: 1.8–132.7), poor Apgar score (<i>p</i> value &#x3c;0.05, OR 12.720, 95% CI: 1.5–111.4), and NICU admissions (<i>p</i> value &#x3c;0.01, OR 9.0, 95% CI: 1.8–45.9). <b><i>Conclusion:</i></b> ICP mothers have low incidence in the UAE and significant association with gestational diabetes and pre-eclampsia. High maternal bile acids above 40 μmol/L have poor fetal outcomes.

The Recurrent Liver Disorder of a Pregnant Mother: Intrahepatic Cholestasis of Pregnancy - A Case Report and Literature Review

Background

Intrahepatic cholestasis of pregnancy (ICP) is a form of liver disease which is unique to pregnancy with a worldwide prevalence ranging from 0.3% and 5.6% of pregnancies. It is presented with skin pruritus and elevated total serum bile salt and liver function test with unknown etiologic agent but suggested hormonal, environmental and genetic risk factors.

Case Presentation

A 31-year-old Gravida III and Para II mother came to University of Gondar specialized hospital at the outpatient clinic in January 2019 with complain of generalized pruritus along with jaundice at 24 weeks gestational age (GA). She presented with singleton and intrauterine pregnancy with a history of one neonatal loss, one living child, and elevated bilirubin, on admission blood serum test showed elevated serum transaminases, and bilirubin. At 30 weeks GA her bilirubin total and bilirubin direct tests were 4.52 mg/dl and 3.45 mg/dl respectively. At 34 weeks GA her bilirubin values became elevated. At 37 weeks GA fetal delivery was carried out via successful caesarean section with an indication of non-reassuring fetal heart rate pattern after induction with oxytocin. The outcome was stable for both mother and baby. After a two week follow up in the outpatient set up, her liver biochemistry test was normal, and free of the clinical features with normal physical growth and intact primitive reflexes of a newborn.

Conclusion

Presenting with a typical marker of increased liver function tests, bilirubin values and pruritus as a clinical feature, ICP was diagnosed. After an attempt at an oxytocin induction, an effective cesarean section was performed to deliver a live female baby, weighing 2.8 kg. The case disappeared after three weeks follow up in the puerperium.

Whole-exome sequencing identifies novel mutations in ABC transporter genes associated with intrahepatic cholestasis of pregnancy disease: a case-control study

Background

Intrahepatic cholestasis of pregnancy (ICP) can cause premature delivery and stillbirth. Previous studies have reported that mutations in ABC transporter genes strongly influence the transport of bile salts. However, to date, their effects are still largely elusive.

Methods

A whole-exome sequencing (WES) approach was used to detect novel variants. Rare novel exonic variants (minor allele frequencies: MAF < 1%) were analyzed. Three web-available tools, namely, SIFT, Mutation Taster and FATHMM, were used to predict protein damage. Protein structure modeling and comparisons between reference and modified protein structures were performed by SWISS-MODEL and Chimera 1.14rc, respectively.

Results

We detected a total of 2953 mutations in 44 ABC family transporter genes. When the MAF of loci was controlled in all databases at less than 0.01, 320 mutations were reserved for further analysis. Among these mutations, 42 were novel. We classified these loci into four groups (the damaging, probably damaging, possibly damaging, and neutral groups) according to the prediction results, of which 7 novel possible pathogenic mutations were identified that were located in known functional genes, including ABCB4 (Trp708Ter, Gly527Glu and Lys386Glu), ABCB11 (Gln1194Ter, Gln605Pro and Leu589Met) and ABCC2 (Ser1342Tyr), in the damaging group. New mutations in the first two genes were reported in our recent article. In addition, compared to the wild-type protein structure, the ABCC2 Ser1342Tyr-modified protein structure showed a slight change in the chemical bond lengths of ATP ligand-binding amino acid side chains. In placental tissue, the expression level of the ABCC2 gene in patients with ICP was significantly higher (P < 0.05) than that in healthy pregnant women. In particular, the patients with two mutations in ABC family genes had higher average values of total bile acids (TBA), aspartate transaminase (AST), direct bilirubin (DBIL), total cholesterol (CHOL), triglycerides (TG) and high-density lipoprotein (HDL) than the patients who had one mutation, no mutation in ABC genes and local controls.

Conclusions

Our present study provide new insight into the genetic architecture of ICP and will benefit the final identification of the underlying mutations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03595-x.

Use of data-independent acquisition mass spectrometry for comparative proteomics analyses of sera from pregnant women with intrahepatic cholestasis of pregnancy

We used data-independent acquisition (DIA) proteomics technology followed by ELISAs and automated biochemical analyses to identify and validate protein expression levels in Intrahepatic Cholestasis of Pregnancy (ICP) and healthy pregnant controls. We employed bioinformatics to identify metabolic processes associated with differentially expressed proteins.The expression levels of two proteins (S100-A9 and the L-lactate dehydrogenase A chain) were significantly higher in ICP patients than in controls; the areas under the receiver operating characteristic (ROC) curves (AUCs) were 0.774 and 0.828, respectively. The expression levels of two other proteins (apolipoprotein A-I and cholinesterase) were significantly lower in patients, with values of 0.900 and 0.842, respectively. Multiple logistic regression showed that a combination of the levels of the four proteins optimized the AUC (0.962), thus more reliably diagnosing ICP. The levels of all four proteins were positively associated with that of total bile acids. Bioinformatics analyses indicated that the four proteins principally affected neutrophil activation involved in the immune response, cell adhesion, lipoprotein metabolism, and the PPAR signaling pathway. SIGNIFICANCE: This preliminary work improves our understanding of changes in serum levels of protein in pregnant women with ICP. The four proteins may serve as novel noninvasive biomarkers for ICP.

Pregnancy outcomes in women with liver disease: Is pregnancy safe? A cross-sectional study

Background

There is evidence suggesting that the pregnancy outcome may be affected by some medical conditions, such as liver diseases.

Objective

The present study aimed to investigate the prevalence of liver disease and its outcomes in pregnant women referred to antenatal clinic in the hospital.

Materials and Methods

In this cross-sectional study, all pregnant women with abnormal liver function test attending antenatal clinic affiliated to Shahid Beheshti University of Medical Sciences were recruited from August 2017 to July 2018. All participants were followed-up until delivery with respect to the maternal and neonatal outcome.

Results

Of a total of 7,121 pregnant women recruited in the study, 110 (1.58%) women were detected with a liver disease; of these, 105 women were diagnosed with pregnancy-specific liver diseases, including HELLP syndrome (10.9%), preeclampsia (50.98%), partial HELLP (0.9%), eclampsia (0.9%), acute fatty liver (9.1%), intra-hepatic cholestasis 25 (22.7%), and 5 women the non-pregnancy-specific liver disease, including Liver transplantation (2.7%), and Autoimmune hepatitis (1.8%). Prevalence of the premature birth was 64.5% in pregnancy-specific liver disease, but no premature birth was detected in cases with liver transplantation. We found that neonatal mortality was significantly associated with neonatal prematurity (p = 0.013), IUGR (p < 0.001), placental pathology (p = 0.04), we had no maternal mortality.

Conclusion

Liver disease is not uncommon in pregnancy. This study demonstrated that pregnancy is safe in women with liver disease.

Maternal hepatitis B infection status and adverse pregnancy outcomes: a retrospective cohort analysis

PURPOSE

To investigate the association between maternal HBsAg-positive status and pregnancy outcomes.

METHODS

The study enrolled women with singleton pregnancies who delivered during January-December 2018. Data of maternal demographics and main adverse pregnancy outcomes were collected from the institutional medical records and analyzed by univariate and multivariate logistic regression models to determine the association between maternal HBV markers (HBsAg/HBeAg/HBV-DNA loads status) and adverse pregnancy outcomes.

RESULTS

Total 1146 HBsAg-positive and 18,354 HBsAg-negative pregnant women were included. After adjusting for potential confounding variables, maternal HBsAg-positive status was associated with a high risk of gestational diabetes mellitus (GDM) [adjusted odds ratio (aOR) = 1.24; 95% confidence interval (CI) 1.07-1.43], intrahepatic cholestasis of pregnancy (ICP) (aOR = 3.83; 95% CI 3.14-4.68), preterm birth (aOR = 1.42; 95% CI 1.17-1.72), and neonatal asphyxia (aOR = 2.20; 95% CI 1.34-3.63). Further, higher risks of ICP and neonatal asphyxia remained with either HBeAg-positive status (aOR = 1.64; 95% CI 1.10-2.44; aOR = 3.08; 95% CI 1.17-8.00) or high HBV-DNA load during the second trimester (aOR = 1.52; 95% CI 1.06-2.35; aOR = 4.20; 95% CI 4.20-15.83) among HBsAg-positive pregnant women.

CONCLUSION

Women with maternal HBsAg-positive status may have increased risks of GDM, ICP, preterm birth, and neonatal asphyxia; furthermore, the risks of ICP and neonatal asphyxia were higher in women with HBeAg-positive status and a high HBV-DNA load during the second trimester among the HBsAg-positive pregnant women, implying that careful surveillance for chronic HBV infection during pregnancy is warranted.

Stillbirth and associated perinatal outcomes in obstetric cholestasis: a systematic review and meta-analysis of observational studies

BACKGROUND

Obstetric cholestasis is a condition occurring in pregnancy with suspected adverse perinatal outcomes. Stillbirth is a significant adverse event associated with obstetric cholestasis and considered for intervention in pregnancy.

OBJECTIVES

There are multiple studies with epidemiological data with regards to the outcomes of obstetric cholestasis. Our hypothesis is to the test the association of stillbirth and related outcomes in obstetric cholestasis.

SEARCH STRATEGY & SELECTION CRITERIA

Two independent reviewers did independent searches and selection with a standardized design as outlined in the PRISMA statement.

ANALYSIS

The retrieved relevant literature was subjected to a rigorous quality assessment and followed by standardized interpretable results.

RESULTS

The pooled estimate in this study showed that there was no significant difference in the stillbirth rates in the obstetric (OC) population when compared to the non-obstetric cholestasis (reference) population. However, there was an increased risk of preterm birth in the OC population compared to the reference population; however, the cesarean section and induction of labor results were directly related.

DISCUSSION

This study provides an epidemiological data related to the perinatal outcomes associated with obstetric cholestasis, specifically stillbirth. This result is likely to produce a benchmark for current evidence-based practice and to assist future research in understanding the implication of associated stillbirth risk and related outcomes with OC.

Association of adverse perinatal outcomes of intrahepatic cholestasis of pregnancy with biochemical markers: results of aggregate and individual patient data meta-analyses

BACKGROUND

Intrahepatic cholestasis of pregnancy is associated with adverse perinatal outcomes, but the association with the concentration of specific biochemical markers is unclear. We aimed to quantify the adverse perinatal effects of intrahepatic cholestasis of pregnancy in women with increased serum bile acid concentrations and determine whether elevated bile acid concentrations were associated with the risk of stillbirth and preterm birth.

METHODS

We did a systematic review by searching PubMed, Web of Science, and Embase databases for studies published from database inception to June 1, 2018, reporting perinatal outcomes for women with intrahepatic cholestasis of pregnancy when serum bile acid concentrations were available. Inclusion criteria were studies defining intrahepatic cholestasis of pregnancy based upon pruritus and elevated serum bile acid concentrations, with or without raised liver aminotransferase concentrations. Eligible studies were case-control, cohort, and population-based studies, and randomised controlled trials, with at least 30 participants, and that reported bile acid concentrations and perinatal outcomes. Studies at potential higher risk of reporter bias were excluded, including case reports, studies not comprising cohorts, or successive cases seen in a unit; we also excluded studies with high risk of bias from groups selected (eg, a subgroup of babies with poor outcomes were explicitly excluded), conference abstracts, and Letters to the Editor without clear peer review. We also included unpublished data from two UK hospitals. We did a random effects meta-analysis to determine risk of adverse perinatal outcomes. Aggregate data for maternal and perinatal outcomes were extracted from case-control studies, and individual patient data (IPD) were requested from study authors for all types of study (as no control group was required for the IPD analysis) to assess associations between biochemical markers and adverse outcomes using logistic and stepwise logistic regression. This study is registered with PROSPERO, number CRD42017069134.

FINDINGS

We assessed 109 full-text articles, of which 23 studies were eligible for the aggregate data meta-analysis (5557 intrahepatic cholestasis of pregnancy cases and 165 136 controls), and 27 provided IPD (5269 intrahepatic cholestasis of pregnancy cases). Stillbirth occurred in 45 (0·83%) of 4936 intrahepatic cholestasis of pregnancy cases and 519 (0·32%) of 163 947 control pregnancies (odds ratio [OR] 1·46 [95% CI 0·73-2·89]; I2=59·8%). In singleton pregnancies, stillbirth was associated with maximum total bile acid concentration (area under the receiver operating characteristic curve [ROC AUC]) 0·83 [95% CI 0·74-0·92]), but not alanine aminotransferase (ROC AUC 0·46 [0·35-0·57]). For singleton pregnancies, the prevalence of stillbirth was three (0·13%; 95% CI 0·02-0·38) of 2310 intrahepatic cholestasis of pregnancy cases in women with serum total bile acids of less than 40 μmol/L versus four (0·28%; 0·08-0·72) of 1412 cases with total bile acids of 40-99 μmol/L (hazard ratio [HR] 2·35 [95% CI 0·52-10·50]; p=0·26), and versus 18 (3·44%; 2·05-5·37) of 524 cases for bile acids of 100 μmol/L or more (HR 30·50 [8·83-105·30]; p<0·0001).

INTERPRETATION

The risk of stillbirth is increased in women with intrahepatic cholestasis of pregnancy and singleton pregnancies when serum bile acids concentrations are of 100 μmol/L or more. Because most women with intrahepatic cholestasis of pregnancy have bile acids below this concentration, they can probably be reassured that the risk of stillbirth is similar to that of pregnant women in the general population, provided repeat bile acid testing is done until delivery.

FUNDING

Tommy's, ICP Support, UK National Institute of Health Research, Wellcome Trust, and Genesis Research Trust.

Perinatal outcomes in intrahepatic cholestasis of pregnancy with monochorionic diamniotic twin pregnancy

BACKGROUND

The primary aim of the study is to investigate the perinatal outcomes in intrahepatic cholestasis of pregnancy (ICP) with monochorionic diamniotic (MCDA) twin pregnancy.

METHODS

This study is a retrospective observational study for women with ICP and MCDA twin pregnancy. Included cases were divided into mild ICP group (10-39 mmol/L) and severe ICP group (> = 40 mmol/L), whose perinatal outcomes were compared between this two groups and whose predictors of adverse perinatal outcomes were evaluated.

RESULTS

37 cases and 21 cases are in mild and severe ICP group respectively, of which, the incidence of gestational diabetes mellitus (GDM) and iatrogenic preterm delivery in severe ICP group are higher than those in mild ICP group. Gestational age (GA) at diagnosis of ICP < 32 weeks is an independent risk factor for GA at delivery < 35 weeks and for composite adverse neonatal outcome. Total bile acids (TBA) > 40 mmol/l is an independent risk factor for meconium-stained amniotic fluid.

CONCLUSION

For women with ICP and MCDA twin pregnancy, GA at diagnosis of ICP < 32 weeks and TBA > 40umol/L are associated with adverse perinatal outcomes.

Sensitivity and Specificity of Biochemical Tests for Diagnosis of Intrahepatic Cholestasis of Pregnancy

BACKGROUND AND AIM

Intrahepatic cholestasis of pregnancy (ICP) is linked with increased risk of fetal complications. An accurate diagnostic test is needed to diagnose this disorder on time. We aimed to assess sensitivity and specificity of laboratory tests used for diagnosis of intrahepatic cholestasis of pregnancy and determine more reliable cut-off values of transaminases.

MATERIAL AND METHODS

Sixty one symptomatic patients with ICP and 29 healthy pregnant women were included in the retrospective analysis.

RESULTS

ICP patients had higher total bile acids (TBA) levels than healthy women (32 vs. 6; P < 0.0001) due to increase in cholic acid (CA) and chenodeoxycholic acid (CDCA). CA/CDCA ratio was significantly higher in ICP patients compared to healthy pregnant women (1.13 vs. 0.68; P < 0.00002). TBA, CA, CDCA and CA/CDCA ratio demonstrate the following sensitivity (94%, 96%, 89%, 71.9%) and specificity (63%, 63%, 59%, 79.3%, respectively) for ICP diagnosis. Lowering cut-off values for ALT (31 U/L) and AST (30 U/L) resulted only in minimal increase of sensitivity to 92.2% vs. 90.1% for ALT and to 92.2%, vs. 90.6% for AST.

CONCLUSION

The present study did not reveal any single specific and sensitive marker for reliable diagnosis of ICP. Establishment of lower cut-off values for transaminases activity might only minimally increase the accuracy of diagnosing ICP.

Effect of Intrahepatic Cholestasis of Pregnancy on Neonatal Birth Weight: A Meta-Analysis

OBJECTIVE

To evaluate the effect of intrahepatic cholestasis of pregnancy (ICP) on neonatal birth weight.

METHODS

Potential articles were identified by searching PubMed and Web of Science databases on April 30th, 2017. Using the Mantel-Haenszel random-effects or fixed-effects model, outcomes were summarized through weighted mean difference (WMD) and 95% confidence intervals (CI). Potential publication bias was tested using a funnel plot and the methods of Egger's regression and Begg's test.

RESULTS

A total of eight studies were included in our meta-analysis. Six studies reported data on neonatal birth weight in ICP and control pregnancies. Pooled data from the six studies showed that the birth weight in the ICP group was significantly lighter than in the control group. The overall pooled WMD was -175 g (95% CI: -301, -48). Meanwhile, pooled data from the other two studies indicated that the birth weight in the late-onset ICP group was heavier than in the early-onset ICP group (WMD: 267 g, 95% CI: 168, 366).

CONCLUSION

Neonatal birth weights in ICP pregnancies were lower than in normal pregnancies. Furthermore, early-onset ICP is associated with a lower birth weight than late-onset ICP.

Targeted metabolomics of sulfated bile acids in urine for the diagnosis and grading of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is related to cholestatic disorder in pregnancy. Total urinary sulfated bile acids (SBAs) were found increased in ICP. We distinguished the metabolic profiling of urinary SBAs in ICP to find potential biomarkers for the diagnosis and grading of ICP. The targeted metabolomics based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to analyze urinary SBAs profiling in mild and severe ICP cases, as well as healthy controls. 16 kinds of urinary SBAs were determined by HPLC-MS/MS. Sulfated dihydroxy glycine bile acid (di-GBA-S), glycine cholic acid 3-sulfate (GCA-3S), sulfated dihydroxy taurine bile acid (di-TBA-S) and taurine cholic acid 3-sulfate (TCA-3S) increased significantly in ICP group compared with the control group. Seven kinds of SBAs were significantly different (p < 0.05) between the ICP group and the control group, with the variable importance in the projection (VIP) value more than one by the orthogonal partial least squares discriminant analysis (OPLS-DA). GCA-3S was well-suited to be used as the biomarker for the diagnosis of ICP with the sensitivity of 100% and specificity of 95.5%. A multi-variable logistic regression containing GCA-3S and di-GBA-S-1 was constructed to distinguish severe ICP from mild ICP, with the sensitivity of 94.4% and specificity of 100%. The developed HPLC-MS/MS method is suitable for the measurement of urinary SBAs profiling. Moreover, the urinary SBAs in the metabolomic profiling have the potential to be used as non-intrusive biomarkers for the diagnosis and grading of ICP.

Can we predict severity of intrahepatic cholestasis of pregnancy using inflammatory markers?

Objective:

To investigate the association of inflammatory markers with severity of intrahepatic cholestasis of pregnancy (ICP).

Materials and Methods:

This retrospective case-control study was conducted with 229 pregnant women, 84 with ICP, and 145 age-matched healthy pregnant women. Patients were categorized as mild ICP (<40 µmol/L) and severe ICP (≥40 µmol/L) with regard to serum bile acids. Inflammatory markers (neutrophil-to-lymphocyte ratio (NLR), platelet-to- lymphocyte ratio (PLR) and mean platelet volume (MPV), and red blood cell distribution width (RDW) were compared between the groups.

Results:

Patients with ICP had significantly decreased RDW and increased white blood cell counts (WBC), MPV and PLR, but no significant changes in NLR. The comparison of mild and severe cases with regard to NLR, PLR, WBC, and RDW was similar (p>0.05). MPV levels were significantly increased in severe group (p<0.05).

Conclusion:

WBC, MPV, and PLR were the inflammatory markers significantly increased, and RDW was signifantly reduced in ICP. MPV was the marker that significantly increased with the severity of disease. The use of inflammatory markers in the assessment of perinatal outcomes needs further studies.

Bile acid levels and risk of adverse perinatal outcomes in intrahepatic cholestasis of pregnancy: A meta-analysis

AIM

We aimed to determine the association between maternal total bile acid (TBA) levels and the risks of adverse perinatal outcomes in pregnant women with intrahepatic cholestasis of pregnancy (ICP) based on a meta-analysis study.

METHODS

We searched PubMed for articles published from 2000 to 2015 with a focus on ICP and restriction to the English language. The main perinatal outcomes were preterm birth (PTB), meconium-stained amniotic fluid (MSAF), asphyxia, or respiratory distress syndrome (RDS). Relative risk (RR) with 95% confidence intervals (CI) was the summary statistic. We used a random- or fixed-effects model to calculate the pooled RR according to the heterogeneity test. Subgroup analyses were performed by region and study design.

RESULTS

Nine eligible related citations fulfilled the inclusion criteria and were included in this study. Compared with pregnant women with a serum TBA < 40 μmol/L, severe ICP (TBA ≥ 40 μmol/L) was associated with a significantly increased risk of adverse fetal outcomes (pooled RR, 1.96; 95%CI, 1.63-2.35), PTB (pooled RR, 2.23; 95%CI, 1.51-3.29), MSAF (pooled RR, 2.27; 95%CI, 1.81-2.85), and asphyxia or RDS (pooled RR, 1.67; 95%CI, 1.18-2.36). Sensitivity analysis suggested that the study design difference may be a major source of heterogeneity. No publication bias was demonstrated by Begg's test (P > 0.05).

CONCLUSION

This meta-analysis indicates that maternal elevated bile acid levels are significantly associated with increased risks of overall adverse perinatal outcomes, PTB, MSAF, and asphyxia or RDS. Serum TBA levels seem to be a useful predictor for the risk of adverse perinatal outcomes.

miR-148a-mediated estrogen-induced cholestasis in intrahepatic cholestasis of pregnancy: Role of PXR/MRP3

Intrahepatic cholestasis of pregnancy (ICP) is an idiopathic liver disease while the biochemical characteristic is the elevated level of total bile acid (TBA). The present study investigated whether miR-148a mediates the induced effect of estrogen on the development of ICP and the proper mechanism: PXR/MRP3 signal pathway. mRNA expression was detected by qPCR, protein expression was detected by western blotting, the concentration of estrogen and TBA were detected by reagent kit respectively. In the cinical research, it was found that miR-148a expression was positive related with the concentration of TBA in the serum of ICP patients. In in vitro research, estradiol (500 nmol/L, 12 h) significantly upregulated miR-148a expression and LV-148a-siRNA inhibited the function of estradiol (500 nmol/L, 48 h) on TBA secretion. In addition, gene silence of miR-148a upregulated PXR expression which was inhibited by estradiol in LO2 cells. Pretreatment of rifampin (10 μmol/L), the agonist of PXR alleviated the TBA secretion induced by estradiol (500 nmol/L, 48 h). miR-148a-siRNA and PXR had a synergistic action on TBA secretion of LO2. Both of miR-148a-siRNA and rifampin (10 μmol/L) inhibited the upregulated effect of estradiol on MRP3 expression. This research has demonstrated that miR-148a may be involved in the induction of estrogen on ICP via PXR signal pathway, and MRP3 may be involved.

Effect of Liver Disease on Hepatic Transporter Expression and Function

Liver disease can alter the disposition of xenobiotics and endogenous substances. Regulatory agencies such as the Food and Drug Administration and the European Medicines Evaluation Agency recommend, if possible, studying the effect of liver disease on drugs under development to guide specific dose recommendations in these patients. Although extensive research has been conducted to characterize the effect of liver disease on drug-metabolizing enzymes, emerging data have implicated that the expression and function of hepatobiliary transport proteins also are altered in liver disease. This review summarizes recent developments in the field, which may have implications for understanding altered disposition, safety, and efficacy of new and existing drugs. A brief review of liver physiology and hepatic transporter localization/function is provided. Then, the expression and function of hepatic transporters in cholestasis, hepatitis C infection, hepatocellular carcinoma, human immunodeficiency virus infection, nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, and primary biliary cirrhosis are reviewed. In the absence of clinical data, nonclinical information in animal models is presented. This review aims to advance the understanding of altered expression and function of hepatic transporters in liver disease and the implications of such changes on drug disposition.

HBsAg positivity during pregnancy and adverse maternal outcomes: a retrospective cohort analysis

Hepatitis B virus infection characterized by HBsAg positivity during pregnancy is a well-recognized issue in developing countries, but the association between HBsAg positivity and adverse maternal outcomes remains uncertain. To examine the association between HBsAg positivity during pregnancy and adverse maternal outcomes, a retrospective cohort study was conducted in Sichuan province, China. Deliveries were recorded from six hospitals between 1 January 2009 and 31 December 2010. Pre-eclampsia, gestational diabetes mellitus (GDM), postpartum haemorrhage (PPH), intrahepatic cholestasis, Caesarean section and placenta previa were prespecified adverse maternal outcomes. We used two multivariate logistic regression models to assess the association between HBsAg positivity and adverse maternal outcomes. In total, 948 (4.2%) pregnant women were HBsAg positive from 22 374 deliveries. Pregnant women with positive HBsAg had higher risk of GDM (aOR1.41, 95%CI 1.15-1.74), PPH (1.44, 1.13-1.83), intrahepatic cholestasis (1.74, 1.40-2.16) and Caesarean section (1.24, 1.06-1.45). No statistical associations were found between HBsAg positivity and pre-eclampsia (1.36, 0.94-1.97), and placenta previa (1.21, 0.87-1.67). HBsAg positivity during pregnancy was associated with higher risk of multiple adverse maternal outcomes. Although the causality has yet to be established, efforts may be warranted in routine care, particularly in those with high risk for adverse maternal outcomes, given the volume population infected with HBsAg. Future studies are needed to establish causality and examine the impact of HBeAg on the adverse outcomes.

[Clinical features of respiratory distress syndrome in neonates of different gestational ages]

OBJECTIVE

To study clinical features of respiratory distress syndrome (RDS) in neonates of different gestational ages (GA).

METHODS

According to GA, 133 neonates with RDS were classified into GA <34 weeks group (n=66), GA 34-36 weeks group (late preterm neonates; n=31), and GA ≥37 weeks group (full-term neonates; n=36). The mothers' medical history during pregnancy and the condition of the neonates at birth were retrospectively analyzed, and the clinical data were compared between groups.

RESULTS

Prenatal corticosteroids supplementation in the GA <34 weeks group was more common than that in the GA 34-36 weeks group (P<0.05). Compared with the GA ≥37 weeks group and the GA 34-36 weeks group, the GA <34 weeks group showed a significantly lower rate of primary diseases, a significantly later time of the development of dyspnea (P<0.05), and a higher rate of intraventricular hemorrhage (P<0.05). Serum albumin levels in the GA <34 weeks group were significantly lower than in the GA ≥37 weeks group (P<0.05). The GA ≥37 weeks group and the GA 34-36 weeks group showed a significantly higher reuse rate of pulmonary surfactant (P<0.05). Use of high-frequency oscillatory ventilation was more common in the GA ≥37 weeks group compared with the GA <34 weeks group (P<0.05).

CONCLUSIONS

The clinical features of RDS are different across neonates of different GA, suggesting that the pathogenesis of RDS may be different in neonates of different GA.

The Interaction of PPARα and CYP7B1 with ERα, β Impacted the Occurrence and Development of Intrahepatic Cholestasis in Pregnant Rats

Intrahepatic cholestasis of pregnancy (ICP) is a disorder of bile acid (BA) synthesis, excretion, and metabolism, with systemic accumulation of BAs, which can lead to prematurity, fetal distress, and intrauterine death. Here, we investigate the expression of peroxisome proliferator-activated receptor alpha and cytochrome P450 oxysterol 7alpha-hydroxylase by exposing to 17α-ethynylestradiol with or without the estrogen receptor signaling pathway in pregnant rats with intrahepatic cholestasis. In vivo and in vitro evidences showed that estrogen receptor alpha (ERα) may be the key point of occurrence and development of intrahepatic cholestasis in pregnant rats. Besides, the abnormalities in genes could be reversed by ERα small interfering RNA. Our findings provide the ERα-centered hypothesis on the mechanisms of ICP. New perspectives are emerging for the treatment of estrogen-induced hepatic complication.