BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-t...BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-threatening situations.Here,we report a patient with mutations in the uridine 5’-diphospho-glucuronosyltrans-ferase 1A1(UGT1A1)and bile salt export pump(adenosine triphosphate-binding cassette subfamily B member 11,ABCB11)genes who presented multiple intrahe-patic bile duct stones and cholestasis,and the jaundice of the patient increased after partial hepatectomy.CASE SUMMARY A 52-year-old male patient admitted to the hospital on October 23,2021,with a progressive exacerbation of jaundice,was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis.Subsequently,the patient underwent left hepatectomy with biliary exploration,stone extraction,T-tube drainage,and cholecystectomy without developing any intraoperative complications.The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments.Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason,including,if not at all,viral infection,cholangitis,autoimmune liver disease,and other causes,the patient underwent whole-exon screening for any genetic diseases,which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes,respectively.Thus,we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient,who eventually declined it and died from liver failure six months later.CONCLUSION Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations.A liver transplant may be the best option if active medical treatment fails.展开更多
Progressive familial intrahepatic cholestasis(PFIC) type 2 is caused by mutations in ABCB11,which encodes bile salt export pump(BSEP).We report a Thai female infant who presented with progressive cholestatic jaundice ...Progressive familial intrahepatic cholestasis(PFIC) type 2 is caused by mutations in ABCB11,which encodes bile salt export pump(BSEP).We report a Thai female infant who presented with progressive cholestatic jaundice since 1 mo of age,with normal serumγ-glutamyltransferase.Immunohistochemical staining of the liver did not demonstrate BSEP along the canaliculi,while multidrug resistance protein 3 was expressed adequately.Novel mutations in ABCB11,a four-nucleotide deletion in exon 3,c.90_93delGAAA,and a single-nucleotide insertion in exon 5,c.249_250insT, were identified,with confirmation in her parents. These mutations were predicted to lead to synthesis of truncated forms of BSEP.Immunostaining and mutation analysis thus established the diagnosis of PFIC type 2.展开更多
AIM: To investigate clinical profiles and mutations of ABCB11 in Koreans with progressive familial intrahepatic cholestasis 2 and review the differences between Koreans and others.METHODS: Of 47 patients with neonatal...AIM: To investigate clinical profiles and mutations of ABCB11 in Koreans with progressive familial intrahepatic cholestasis 2 and review the differences between Koreans and others.METHODS: Of 47 patients with neonatal cholestasis, five infants had chronic intrahepatic cholestasis with normal γ-glutamyl transpeptidase. Direct sequencing analyses of ABCB11, including exons and introns, were performed from peripheral blood.RESULTS: Living donor-liver transplantation was performed in four patients because of rapidly progressive hepatic failure and hepatocellular carcinoma. Three missense mutations were found in two patients: compound heterozygous 677C>T(S226L)/3007G>A(G1003R) and heterozygous 2296G>A(G766R). The mutations were located near and in the transmembranous space. CONCLUSION: Alterations in the transmembrane of the bile salt export pump in the Korean infants were different from those previously reported in Chinese, Japanease, Taiwan Residents, and European patients.展开更多
Background/Aims: Inherited dysfunction of the bile salt export pump BSEP (ABCB11) causes a progressive and a benign form of familial intrahepatic cholestasis, denominated as PFIC2 and BRIC2, respectively. We functiona...Background/Aims: Inherited dysfunction of the bile salt export pump BSEP (ABCB11) causes a progressive and a benign form of familial intrahepatic cholestasis, denominated as PFIC2 and BRIC2, respectively. We functionally characterized novel ABCB11 mutations encountered in two patients with a PFIC2 and a BRIC2 phenotype, respectively. Methods: BSEP expression was determined in liver biopsies by immunohistochemistry. ABCB11 mutations were functionally characterized by taurocholate transport in SF9 cells transfected with human ABCB11. Results: The PFIC2 patient was compound heterozygous for a splicingmutation in intron 4 ((+ 3)A >C) combined with an early stop codon at position 930 (R930X), while the BRIC2 patient was compound heterozygous for two nonsynonymous mutations in exon 9 (E297G) and exon 12 (R432T), respectively. Hepatic BSEP expression was absent in PFIC2 and preserved in BRIC2. In BRIC2, taurocholate transport was decreased to 13% and 20% of reference levels for R432T and E297G, respectively. Conclusions: The intron 4 (+ 3)A >C, R930X and R432T represent previously undescribed mutations of the ABCB11 gene that confer a PFIC2 and a BRIC2 phenotype, respectively. By combining functional in-vitro characterization with immunohistochemical detection of variant BSEP we provide direct evidence for the role of ABCB11 mutations in the pathogenesis of different forms of intrahepatic cholestasis.展开更多
Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretio...Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretion,and/or caused by defects in the secretory machinery of cholangiocytes.Several mutations and pathways that lead to cholestasis have been described.Progressive familial intrahepatic cholestasis(PFIC)is a group of rare diseases caused by autosomal recessive mutations in the genes that encode proteins expressed mainly in the apical membrane of the hepatocytes.PFIC 1,also known as Byler’s disease,is caused by mutations of the ATP8B1 gene,which encodes the familial intrahepatic cholestasis 1 protein.PFIC 2 is characterized by the downregulation or absence of functional bile salt export pump(BSEP)expression via variations in the ABCB11 gene.Mutations of the ABCB4 gene result in lower expression of the multidrug resistance class 3 glycoprotein,leading to the third type of PFIC.Newer variations of this disease have been described.Loss of function of the tight junction protein 2 protein results in PFIC 4,while mutations of the NR1H4 gene,which encodes farnesoid X receptor,an important transcription factor for bile formation,cause PFIC 5.A recently described type of PFIC is associated with a mutation in the MYO5B gene,important for the trafficking of BSEP and hepatocyte membrane polarization.In this review,we provide a brief overview of the molecular mechanisms and clinical features associated with each type of PFIC based on peer reviewed journals published between 1993 and 2020.展开更多
基金Supported by The Science and Technology Planning Projects of Guizhou Province and Zunyi City,No.QKHJCZK[2022]YB642,No.ZSKH·HZ(2022)344,No.gzwjkj2021-071,ZMC·YZ[2018]38,No.ZSKH·HZ[2021]58,and No.ZSKH·HZ[2021]60The General Project of Hubei Province and Jingmen City,No.2021YFYB074.
文摘BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-threatening situations.Here,we report a patient with mutations in the uridine 5’-diphospho-glucuronosyltrans-ferase 1A1(UGT1A1)and bile salt export pump(adenosine triphosphate-binding cassette subfamily B member 11,ABCB11)genes who presented multiple intrahe-patic bile duct stones and cholestasis,and the jaundice of the patient increased after partial hepatectomy.CASE SUMMARY A 52-year-old male patient admitted to the hospital on October 23,2021,with a progressive exacerbation of jaundice,was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis.Subsequently,the patient underwent left hepatectomy with biliary exploration,stone extraction,T-tube drainage,and cholecystectomy without developing any intraoperative complications.The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments.Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason,including,if not at all,viral infection,cholangitis,autoimmune liver disease,and other causes,the patient underwent whole-exon screening for any genetic diseases,which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes,respectively.Thus,we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient,who eventually declined it and died from liver failure six months later.CONCLUSION Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations.A liver transplant may be the best option if active medical treatment fails.
文摘Progressive familial intrahepatic cholestasis(PFIC) type 2 is caused by mutations in ABCB11,which encodes bile salt export pump(BSEP).We report a Thai female infant who presented with progressive cholestatic jaundice since 1 mo of age,with normal serumγ-glutamyltransferase.Immunohistochemical staining of the liver did not demonstrate BSEP along the canaliculi,while multidrug resistance protein 3 was expressed adequately.Novel mutations in ABCB11,a four-nucleotide deletion in exon 3,c.90_93delGAAA,and a single-nucleotide insertion in exon 5,c.249_250insT, were identified,with confirmation in her parents. These mutations were predicted to lead to synthesis of truncated forms of BSEP.Immunostaining and mutation analysis thus established the diagnosis of PFIC type 2.
文摘AIM: To investigate clinical profiles and mutations of ABCB11 in Koreans with progressive familial intrahepatic cholestasis 2 and review the differences between Koreans and others.METHODS: Of 47 patients with neonatal cholestasis, five infants had chronic intrahepatic cholestasis with normal γ-glutamyl transpeptidase. Direct sequencing analyses of ABCB11, including exons and introns, were performed from peripheral blood.RESULTS: Living donor-liver transplantation was performed in four patients because of rapidly progressive hepatic failure and hepatocellular carcinoma. Three missense mutations were found in two patients: compound heterozygous 677C>T(S226L)/3007G>A(G1003R) and heterozygous 2296G>A(G766R). The mutations were located near and in the transmembranous space. CONCLUSION: Alterations in the transmembrane of the bile salt export pump in the Korean infants were different from those previously reported in Chinese, Japanease, Taiwan Residents, and European patients.
文摘Background/Aims: Inherited dysfunction of the bile salt export pump BSEP (ABCB11) causes a progressive and a benign form of familial intrahepatic cholestasis, denominated as PFIC2 and BRIC2, respectively. We functionally characterized novel ABCB11 mutations encountered in two patients with a PFIC2 and a BRIC2 phenotype, respectively. Methods: BSEP expression was determined in liver biopsies by immunohistochemistry. ABCB11 mutations were functionally characterized by taurocholate transport in SF9 cells transfected with human ABCB11. Results: The PFIC2 patient was compound heterozygous for a splicingmutation in intron 4 ((+ 3)A >C) combined with an early stop codon at position 930 (R930X), while the BRIC2 patient was compound heterozygous for two nonsynonymous mutations in exon 9 (E297G) and exon 12 (R432T), respectively. Hepatic BSEP expression was absent in PFIC2 and preserved in BRIC2. In BRIC2, taurocholate transport was decreased to 13% and 20% of reference levels for R432T and E297G, respectively. Conclusions: The intron 4 (+ 3)A >C, R930X and R432T represent previously undescribed mutations of the ABCB11 gene that confer a PFIC2 and a BRIC2 phenotype, respectively. By combining functional in-vitro characterization with immunohistochemical detection of variant BSEP we provide direct evidence for the role of ABCB11 mutations in the pathogenesis of different forms of intrahepatic cholestasis.
基金Supported by NIH,No.UG3TR003289 to Soto-Gutierrez A.
文摘Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretion,and/or caused by defects in the secretory machinery of cholangiocytes.Several mutations and pathways that lead to cholestasis have been described.Progressive familial intrahepatic cholestasis(PFIC)is a group of rare diseases caused by autosomal recessive mutations in the genes that encode proteins expressed mainly in the apical membrane of the hepatocytes.PFIC 1,also known as Byler’s disease,is caused by mutations of the ATP8B1 gene,which encodes the familial intrahepatic cholestasis 1 protein.PFIC 2 is characterized by the downregulation or absence of functional bile salt export pump(BSEP)expression via variations in the ABCB11 gene.Mutations of the ABCB4 gene result in lower expression of the multidrug resistance class 3 glycoprotein,leading to the third type of PFIC.Newer variations of this disease have been described.Loss of function of the tight junction protein 2 protein results in PFIC 4,while mutations of the NR1H4 gene,which encodes farnesoid X receptor,an important transcription factor for bile formation,cause PFIC 5.A recently described type of PFIC is associated with a mutation in the MYO5B gene,important for the trafficking of BSEP and hepatocyte membrane polarization.In this review,we provide a brief overview of the molecular mechanisms and clinical features associated with each type of PFIC based on peer reviewed journals published between 1993 and 2020.
