BACKGROUND Mutations that occur in the ABCB4 gene,which encodes multidrug-resistant protein 3,underlie the occurrence of progressive familial intrahepatic cholestasis type 3(PFIC3).Clinical signs of intrahepatic chole...BACKGROUND Mutations that occur in the ABCB4 gene,which encodes multidrug-resistant protein 3,underlie the occurrence of progressive familial intrahepatic cholestasis type 3(PFIC3).Clinical signs of intrahepatic cholestasis due to gene mutations typically first appear during infancy or childhood.Reports of PFIC3 occurring in adults are rare.CASE SUMMARY This is a case study of a 32-year-old infertile female Chinese patient with a 15-year history of recurrent abnormal liver function.Her primary clinical signs were elevated levels of alkaline phosphatase andγ-glutamyl transpeptidase.Other possible reasons for liver dysfunction were eliminated in this patient,resulting in a diagnosis of PFIC3.The diagnosis was confirmed using gene detection and histological analyses.Assessments using genetic sequencing analysis indicated the presence of two novel heterozygous mutations in the ABCB4 gene,namely,a 2950C>T;p.A984V mutation(exon 24)and a 667A>G;p.I223V mutation(exon 7).After receiving ursodeoxycholic acid(UDCA)treatment,the patient's liver function indices improved,and she successfully became pregnant by in vitro fertilization.However,the patient developed intrahepatic cholestasis of pregnancy in the first trimester.Fortunately,treatment with UDCA was safe and effective.CONCLUSION These novel ABCB4 heterozygous mutations have a variety of clinical phenotypes.Continued follow-up is essential for a comprehensive understanding of PFIC3.展开更多
Progressive familial intrahepatic cholestasis type 3 is caused by a mutation in the ATP-binding cassette, subfamily B, member 4 (ABCB4) gene encoding multidrug resistance protein 3. A 32-year-old woman with a history ...Progressive familial intrahepatic cholestasis type 3 is caused by a mutation in the ATP-binding cassette, subfamily B, member 4 (ABCB4) gene encoding multidrug resistance protein 3. A 32-year-old woman with a history of acute hepatitis at age 9 years was found to have jaundice during pregnancy in 2008, and was diagnosed as having intrahepatic cholestasis of pregnancy. In 2009, she underwent cholecystectomy for gallstones and chronic cholecystitis. However, itching and jaundice did not resolve postoperatively. She was admitted to our hospital with fatigue, jaundice, and a recently elevated γ-glutamyl transpeptidase level. Liver biopsy led to the diagnosis of biliary cirrhosis with ductopenia. Genetic testing revealed a pathogenic heterozygous mutation, ex13 c.1531G > A (p.A511 T), in the ABCB4 gene. Her father did not carry the mutation, but her mother's brother carried the heterozygous mutation. We made a definitivediagnosis of familial intrahepatic cholestasis type 3. He symptoms and liver function improved after 3 mo o treatment with ursodeoxycholic acid.展开更多
BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have bee...BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have been linked to PFIC type 4(PFIC4),which predominantly presents in childhood.However,there are only limited data from adults with TJP2-related PFIC4.We report a family with an autosomal recessive disorder with a novel variant in the TJP2 gene in adults with very variable expression of PFIC4.CASE SUMMARY The index patient presented at 19 years old with liver cirrhosis and variceal bleeding and was treated with endoscopic banding and beta-blockers.In 2018,he developed primary liver cancer that was treated with radiofrequency ablation followed by liver transplantation in 2019.Genetic testing revealed a novel homozygous TJP2 variant causing PFIC4(TJP2([NM_004817.3]:c.[3334C>T];[3334C>T])).The consanguineous family consists of the father and mother(both heterozygous)and their 12 children,of which five carry the variant in a homozygous state;however,these five siblings have highly variable expression of PFIC4.Two homozygous brothers had cirrhosis and portal hypertension at diagnosis at the ages of 19 and 36.Two other homozygous brothers,age 23 and 19,and the homozygous sister,age 21,have elevated liver enzymes but presently no cirrhosis,which may suggest an age-dependent penetrance.In addition,five sisters had severe and mild intrahepatic cholestasis of pregnancy and carry the TJP2 variant in a homozygous and heterozygous state,respectively.CONCLUSION This novel TJP2 variant is associated with PFIC4 causing severe liver disease with cirrhosis and primary liver cancer in adolescents/adults.展开更多
BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)refers to a disparate group of autosomal recessive disorders that are linked by the inability to appropriately form and excrete bile from hepatocytes,resul...BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)refers to a disparate group of autosomal recessive disorders that are linked by the inability to appropriately form and excrete bile from hepatocytes,resulting in a hepatocellular form of cholestasis.While the diagnosis of such disorders had historically been based on pattern recognition of unremitting cholestasis without other identified molecular or anatomic cause,recent scientific advancements have uncovered multiple specific responsible proteins.The variety of identified defects has resulted in an ever-broadening phenotypic spectrum,ranging from traditional benign recurrent jaundice to progressive cholestasis and end-stage liver disease.AIM To review current data on defects in bile acid homeostasis,explore the expanding knowledge base of genetic based diseases in this field,and report disease characteristics and management.METHODS We conducted a systemic review according to PRISMA guidelines.We performed a Medline/PubMed search in February-March 2019 for relevant articles relating to the understanding,diagnosis,and management of bile acid homeostasis with a focus on the family of diseases collectively known as PFIC.English only articles were accessed in full.The manual search included references of retrieved articles.We extracted data on disease characteristics,associations with other diseases,and treatment.Data was summarized and presented in text,figure,and table format.RESULTS Genetic-based liver disease resulting in the inability to properly form and secrete bile constitute an important cause of morbidity and mortality in children and increasingly in adults.A growing number of PFIC have been described based on an expanded understanding of biliary transport mechanism defects and the development of a common phenotype.CONCLUSION We present a summary of current advances made in a number of areas relevant to both the classically described FIC1(ATP8B1),BSEP(ABCB11),and MDR3(ABCB4)transporter deficiencies,as well as more recently described gene mutations--TJP2(TJP2),FXR(NR1H4),MYO5B(MYO5B),and others which expand the etiology and understanding of PFIC-related cholestatic diseases and bile transport.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
BACKGROUND:Three types of progressive familial intrahepatic cholestasis(PFIC)have been identified,but their etiologies include unknown mechanisms. DATA SOURCES:A PubMed search on'progressive familial intrahepatic ...BACKGROUND:Three types of progressive familial intrahepatic cholestasis(PFIC)have been identified,but their etiologies include unknown mechanisms. DATA SOURCES:A PubMed search on'progressive familial intrahepatic cholestasis'and'PFIC'was performed on the topic,and the relevant articles were reviewed. RESULTS:The etiologies of the three PFIC types still include unknown mechanisms.Especially in PFIC type 1,enterohepatic circulation of bile acid should be considered.Ursodeoxycholic acid,partial external biliary diversion and liver transplantation have been used for the treatment of PFIC patients according to disease course. CONCLUSIONS:Since the etiologies and disease mechanisms of PFIC are still unclear,detailed studies are urgently required. Strategies for more advanced therapies are also needed.These developments in the future are indispensable,especially for PFIC type 1 patients.展开更多
Progressive familial intrahepatic cholestasis(PFIC) is a constellation of inherited disorders that result in the impairment of bile flow through the liver that predominantly affects children. The accumulation of bile ...Progressive familial intrahepatic cholestasis(PFIC) is a constellation of inherited disorders that result in the impairment of bile flow through the liver that predominantly affects children. The accumulation of bile results in progressive liver damage, and if left untreated leads to end stage liver disease and death. Patients often present with worsening jaundice and pruritis within the first few years of life. Many of these patients will progress to end stage liver disease and require liver transplantation. The role and timing of liver transplantation still remains debated especially in the management of PFIC1. In those patients who are appropriately selected, liver transplantation offers an excellent survival benefit. Appropriate timing and selection of patients for liver transplantation will be discussed, and the short and long term management of patients post liver transplantation will also be described.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
Progressive familial intrahepatic cholestasis type 1 is a rare disease that is characterized by low serum γ-glutamyltransferase levels due to mutation inATP8B1.We present a 23-year-old male who experienced persistent...Progressive familial intrahepatic cholestasis type 1 is a rare disease that is characterized by low serum γ-glutamyltransferase levels due to mutation inATP8B1.We present a 23-year-old male who experienced persistent marked pruritus for eighteen years and recurrent jaundice for thirteen years,in addition to cholestasis that eventually became fatal.Genetic sequencing studies of the entire coding(exon) sequences of ATP8B1 and ABCB11 uncovered a novel heterozygous missense 3035G>T mutation(S1012I) and a synonymous 696T>C mutation in ATP8B1.The patient's progression was associated with not only impaired familial intrahepatic cholestasis 1(FIC1) function but also impaired bile salt export pump expression due to the impaired FIC1 function.Our findings show that patients with intermittent cholestasis can develop progressive liver disease even after several decades and require regular follow up.展开更多
BACKGROUND Functioning farnesoid X receptor(FXR;encoded by NR1H4)is key to normal bile acid homeostasis.Biallelic mutations in NR1H4 are reported in a few children with intrahepatic cholestasis.We describe a boy with ...BACKGROUND Functioning farnesoid X receptor(FXR;encoded by NR1H4)is key to normal bile acid homeostasis.Biallelic mutations in NR1H4 are reported in a few children with intrahepatic cholestasis.We describe a boy with progressive familial intrahepatic cholestasis and homozygous mutation in NR1H4.CASE SUMMARY A boy had severe neonatal cholestasis with moderate hypercholanemia and persistently elevated alpha-fetoprotein.Despite medical treatment,coagulopathy was uncontrollable,prompting liver transplantation at age 8 mo with incidental splenectomy.The patient experienced catch-up growth with good liver function and did not develop allograft steatosis.However,1 year after transplant,he died from an acute infection,considered secondary to immunosuppression and asplenia.A homozygous protein-truncating mutation,c.547C>T,p.(Arg183Ter),was subsequently identified in NR1H4,and both parents were shown to be heterozygous carriers.Absence of FXR and of bile salt export pump expression was confirmed by immunostaining of explanted liver.CONCLUSION Severe cholestasis with persistently high alpha-fetoprotein and modest elevation of serum bile acid levels may suggest FXR deficiency.Some patients with FXR deficiency may not develop allograft steatosis and may respond well to liver transplantation.展开更多
Progressive familial intrahepatic cholestasis(PFIC)is a heterogeneous group of disorders characterized by defects in bile secretion and presentation with intrahepatic cholestasis in infancy or childhood.The most commo...Progressive familial intrahepatic cholestasis(PFIC)is a heterogeneous group of disorders characterized by defects in bile secretion and presentation with intrahepatic cholestasis in infancy or childhood.The most common types include PFIC 1(deficiency of FIC1 protein,ATP8B1 gene mutation),PFIC 2(bile salt export pump deficiency,ABCB11 gene mutation),and PFIC 3(multidrug resistance protein-3 deficiency,ABCB4 gene mutation).Mutational analysis of subjects with normal gamma-glutamyl transferase cholestasis of unknown etiology has led to the identification of newer variants of PFIC,known as PFIC 4,5,and MYO5B related(sometimes known as PFIC 6).PFIC 4 is caused by the loss of function of tight junction protein 2(TJP2)and PFIC 5 is due to NR1H4 mutation causing Farnesoid X receptor deficiency.MYO5B gene mutation causes microvillous inclusion disease(MVID)and is also associated with isolated cholestasis.Children with TJP2 related cholestasis(PFIC-4)have a variable spectrum of presentation.Some have a self-limiting disease,while others have progressive liver disease with an increased risk of hepatocellular carcinoma.Hence,frequent surveillance for hepatocellular carcinoma is recommended from infancy.PFIC-5 patients usually have rapidly progressive liver disease with early onset coagulopathy,high alpha-fetoprotein and ultimately require a liver transplant.Subjects with MYO5 B-related disease can present with isolated cholestasis or cholestasis with intractable diarrhea(MVID).These children are at risk of worsening cholestasis post intestinal transplant(IT)for MVID,hence combined intestinal and liver transplant or IT with biliary diversion is preferred.Immunohistochemistry can differentiate most of the variants of PFIC but confirmation requires genetic analysis.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
Cholestatic liver disease consists of a variety of disorders.Primary sclerosing cholangitis and primary biliary cirrhosis are the most commonly recognized cholestatic liver disease in the adult population,while biliar...Cholestatic liver disease consists of a variety of disorders.Primary sclerosing cholangitis and primary biliary cirrhosis are the most commonly recognized cholestatic liver disease in the adult population,while biliary atresia and Alagille syndrome are commonly recognized in the pediatric population.In infants,the causes are usually congenital or inherited.Even though jaundice is a hallmark of cholestasis,it is not always seen in adult patients with chronic liver disease.Patients can have"silent"progressive cholestatic liver disease for years prior to development of symptoms such as jaundice and pruritus.In this review,we will discuss some of the atypical causes of cholestatic liver disease such as benign recurrent intrahepatic cholestasis,progressive familial intrahepatic cholestasis,Alagille Syndrome,biliary atresia,total parenteral nutrition induced cholestasis and cholestasis secondary to drug induced liver injury.展开更多
BACKGROUND Gene mutations in ATP-binding cassette,subfamily B(ABCB4)lead to autosomal recessive disorders.Primary light amyloidosis is a rare and incurable disease.Here,we report a rare case of liver cirrhosis caused ...BACKGROUND Gene mutations in ATP-binding cassette,subfamily B(ABCB4)lead to autosomal recessive disorders.Primary light amyloidosis is a rare and incurable disease.Here,we report a rare case of liver cirrhosis caused by ABCB4 gene mutation combined with primary light amyloidosis.CASE SUMMARY We report a case of a 25-year-old female who was hospitalized due to recurrent abdominal pain caused by calculous cholecystitis and underwent cholecystectomy.Pathological examination of the liver tissue suggested liver cirrhosis with bile duct injury.Exon analyses of the whole genome from the patient’s peripheral blood revealed the presence of a heterozygous mutation in the ABCB4 gene.Bone marrow biopsy tissues,renal puncture examination,and liver mass spectrometry confirmed the diagnosis of a rare progressive familial intrahepatic cholestasis type 3 with systemic light chain type κ amyloidosis,which resulted in cirrhosis.Ursodeoxycholic acid and the cluster of differentiation 38 monoclonal antibody daretozumab were administered for treatment.Following treatment,the patient demonstrated significant improvement.Urinary protein became negative,peripheral blood-free light chain and urine-free light chain levels returned to normal,and the electrocardiogram showed no abnormalities.Additionally,the patient’s lower limb numbness resolved,and her condition remained stable.CONCLUSION This report presents the diagnosis and treatment of liver cirrhosis,a rare disease that is easily misdiagnosed or missed.展开更多
基金Supported by Natural Science Foundation of Gansu Province,No.21JR7RA410.
文摘BACKGROUND Mutations that occur in the ABCB4 gene,which encodes multidrug-resistant protein 3,underlie the occurrence of progressive familial intrahepatic cholestasis type 3(PFIC3).Clinical signs of intrahepatic cholestasis due to gene mutations typically first appear during infancy or childhood.Reports of PFIC3 occurring in adults are rare.CASE SUMMARY This is a case study of a 32-year-old infertile female Chinese patient with a 15-year history of recurrent abnormal liver function.Her primary clinical signs were elevated levels of alkaline phosphatase andγ-glutamyl transpeptidase.Other possible reasons for liver dysfunction were eliminated in this patient,resulting in a diagnosis of PFIC3.The diagnosis was confirmed using gene detection and histological analyses.Assessments using genetic sequencing analysis indicated the presence of two novel heterozygous mutations in the ABCB4 gene,namely,a 2950C>T;p.A984V mutation(exon 24)and a 667A>G;p.I223V mutation(exon 7).After receiving ursodeoxycholic acid(UDCA)treatment,the patient's liver function indices improved,and she successfully became pregnant by in vitro fertilization.However,the patient developed intrahepatic cholestasis of pregnancy in the first trimester.Fortunately,treatment with UDCA was safe and effective.CONCLUSION These novel ABCB4 heterozygous mutations have a variety of clinical phenotypes.Continued follow-up is essential for a comprehensive understanding of PFIC3.
文摘Progressive familial intrahepatic cholestasis type 3 is caused by a mutation in the ATP-binding cassette, subfamily B, member 4 (ABCB4) gene encoding multidrug resistance protein 3. A 32-year-old woman with a history of acute hepatitis at age 9 years was found to have jaundice during pregnancy in 2008, and was diagnosed as having intrahepatic cholestasis of pregnancy. In 2009, she underwent cholecystectomy for gallstones and chronic cholecystitis. However, itching and jaundice did not resolve postoperatively. She was admitted to our hospital with fatigue, jaundice, and a recently elevated γ-glutamyl transpeptidase level. Liver biopsy led to the diagnosis of biliary cirrhosis with ductopenia. Genetic testing revealed a pathogenic heterozygous mutation, ex13 c.1531G > A (p.A511 T), in the ABCB4 gene. Her father did not carry the mutation, but her mother's brother carried the heterozygous mutation. We made a definitivediagnosis of familial intrahepatic cholestasis type 3. He symptoms and liver function improved after 3 mo o treatment with ursodeoxycholic acid.
基金Supported by Sanming Project of Medicine in Shenzhen of China,No.SZSM201612074
文摘BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have been linked to PFIC type 4(PFIC4),which predominantly presents in childhood.However,there are only limited data from adults with TJP2-related PFIC4.We report a family with an autosomal recessive disorder with a novel variant in the TJP2 gene in adults with very variable expression of PFIC4.CASE SUMMARY The index patient presented at 19 years old with liver cirrhosis and variceal bleeding and was treated with endoscopic banding and beta-blockers.In 2018,he developed primary liver cancer that was treated with radiofrequency ablation followed by liver transplantation in 2019.Genetic testing revealed a novel homozygous TJP2 variant causing PFIC4(TJP2([NM_004817.3]:c.[3334C>T];[3334C>T])).The consanguineous family consists of the father and mother(both heterozygous)and their 12 children,of which five carry the variant in a homozygous state;however,these five siblings have highly variable expression of PFIC4.Two homozygous brothers had cirrhosis and portal hypertension at diagnosis at the ages of 19 and 36.Two other homozygous brothers,age 23 and 19,and the homozygous sister,age 21,have elevated liver enzymes but presently no cirrhosis,which may suggest an age-dependent penetrance.In addition,five sisters had severe and mild intrahepatic cholestasis of pregnancy and carry the TJP2 variant in a homozygous and heterozygous state,respectively.CONCLUSION This novel TJP2 variant is associated with PFIC4 causing severe liver disease with cirrhosis and primary liver cancer in adolescents/adults.
文摘BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)refers to a disparate group of autosomal recessive disorders that are linked by the inability to appropriately form and excrete bile from hepatocytes,resulting in a hepatocellular form of cholestasis.While the diagnosis of such disorders had historically been based on pattern recognition of unremitting cholestasis without other identified molecular or anatomic cause,recent scientific advancements have uncovered multiple specific responsible proteins.The variety of identified defects has resulted in an ever-broadening phenotypic spectrum,ranging from traditional benign recurrent jaundice to progressive cholestasis and end-stage liver disease.AIM To review current data on defects in bile acid homeostasis,explore the expanding knowledge base of genetic based diseases in this field,and report disease characteristics and management.METHODS We conducted a systemic review according to PRISMA guidelines.We performed a Medline/PubMed search in February-March 2019 for relevant articles relating to the understanding,diagnosis,and management of bile acid homeostasis with a focus on the family of diseases collectively known as PFIC.English only articles were accessed in full.The manual search included references of retrieved articles.We extracted data on disease characteristics,associations with other diseases,and treatment.Data was summarized and presented in text,figure,and table format.RESULTS Genetic-based liver disease resulting in the inability to properly form and secrete bile constitute an important cause of morbidity and mortality in children and increasingly in adults.A growing number of PFIC have been described based on an expanded understanding of biliary transport mechanism defects and the development of a common phenotype.CONCLUSION We present a summary of current advances made in a number of areas relevant to both the classically described FIC1(ATP8B1),BSEP(ABCB11),and MDR3(ABCB4)transporter deficiencies,as well as more recently described gene mutations--TJP2(TJP2),FXR(NR1H4),MYO5B(MYO5B),and others which expand the etiology and understanding of PFIC-related cholestatic diseases and bile transport.
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.
文摘BACKGROUND:Three types of progressive familial intrahepatic cholestasis(PFIC)have been identified,but their etiologies include unknown mechanisms. DATA SOURCES:A PubMed search on'progressive familial intrahepatic cholestasis'and'PFIC'was performed on the topic,and the relevant articles were reviewed. RESULTS:The etiologies of the three PFIC types still include unknown mechanisms.Especially in PFIC type 1,enterohepatic circulation of bile acid should be considered.Ursodeoxycholic acid,partial external biliary diversion and liver transplantation have been used for the treatment of PFIC patients according to disease course. CONCLUSIONS:Since the etiologies and disease mechanisms of PFIC are still unclear,detailed studies are urgently required. Strategies for more advanced therapies are also needed.These developments in the future are indispensable,especially for PFIC type 1 patients.
文摘Progressive familial intrahepatic cholestasis(PFIC) is a constellation of inherited disorders that result in the impairment of bile flow through the liver that predominantly affects children. The accumulation of bile results in progressive liver damage, and if left untreated leads to end stage liver disease and death. Patients often present with worsening jaundice and pruritis within the first few years of life. Many of these patients will progress to end stage liver disease and require liver transplantation. The role and timing of liver transplantation still remains debated especially in the management of PFIC1. In those patients who are appropriately selected, liver transplantation offers an excellent survival benefit. Appropriate timing and selection of patients for liver transplantation will be discussed, and the short and long term management of patients post liver transplantation will also be described.
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Progressive familial intrahepatic cholestasis type 1 is a rare disease that is characterized by low serum γ-glutamyltransferase levels due to mutation inATP8B1.We present a 23-year-old male who experienced persistent marked pruritus for eighteen years and recurrent jaundice for thirteen years,in addition to cholestasis that eventually became fatal.Genetic sequencing studies of the entire coding(exon) sequences of ATP8B1 and ABCB11 uncovered a novel heterozygous missense 3035G>T mutation(S1012I) and a synonymous 696T>C mutation in ATP8B1.The patient's progression was associated with not only impaired familial intrahepatic cholestasis 1(FIC1) function but also impaired bile salt export pump expression due to the impaired FIC1 function.Our findings show that patients with intermittent cholestasis can develop progressive liver disease even after several decades and require regular follow up.
基金National Institutes of Health,No.R01DK094828and National Human Genome Research Institute,No.UM1 HG006493 and No.U24 HG008956.
文摘BACKGROUND Functioning farnesoid X receptor(FXR;encoded by NR1H4)is key to normal bile acid homeostasis.Biallelic mutations in NR1H4 are reported in a few children with intrahepatic cholestasis.We describe a boy with progressive familial intrahepatic cholestasis and homozygous mutation in NR1H4.CASE SUMMARY A boy had severe neonatal cholestasis with moderate hypercholanemia and persistently elevated alpha-fetoprotein.Despite medical treatment,coagulopathy was uncontrollable,prompting liver transplantation at age 8 mo with incidental splenectomy.The patient experienced catch-up growth with good liver function and did not develop allograft steatosis.However,1 year after transplant,he died from an acute infection,considered secondary to immunosuppression and asplenia.A homozygous protein-truncating mutation,c.547C>T,p.(Arg183Ter),was subsequently identified in NR1H4,and both parents were shown to be heterozygous carriers.Absence of FXR and of bile salt export pump expression was confirmed by immunostaining of explanted liver.CONCLUSION Severe cholestasis with persistently high alpha-fetoprotein and modest elevation of serum bile acid levels may suggest FXR deficiency.Some patients with FXR deficiency may not develop allograft steatosis and may respond well to liver transplantation.
文摘Progressive familial intrahepatic cholestasis(PFIC)is a heterogeneous group of disorders characterized by defects in bile secretion and presentation with intrahepatic cholestasis in infancy or childhood.The most common types include PFIC 1(deficiency of FIC1 protein,ATP8B1 gene mutation),PFIC 2(bile salt export pump deficiency,ABCB11 gene mutation),and PFIC 3(multidrug resistance protein-3 deficiency,ABCB4 gene mutation).Mutational analysis of subjects with normal gamma-glutamyl transferase cholestasis of unknown etiology has led to the identification of newer variants of PFIC,known as PFIC 4,5,and MYO5B related(sometimes known as PFIC 6).PFIC 4 is caused by the loss of function of tight junction protein 2(TJP2)and PFIC 5 is due to NR1H4 mutation causing Farnesoid X receptor deficiency.MYO5B gene mutation causes microvillous inclusion disease(MVID)and is also associated with isolated cholestasis.Children with TJP2 related cholestasis(PFIC-4)have a variable spectrum of presentation.Some have a self-limiting disease,while others have progressive liver disease with an increased risk of hepatocellular carcinoma.Hence,frequent surveillance for hepatocellular carcinoma is recommended from infancy.PFIC-5 patients usually have rapidly progressive liver disease with early onset coagulopathy,high alpha-fetoprotein and ultimately require a liver transplant.Subjects with MYO5 B-related disease can present with isolated cholestasis or cholestasis with intractable diarrhea(MVID).These children are at risk of worsening cholestasis post intestinal transplant(IT)for MVID,hence combined intestinal and liver transplant or IT with biliary diversion is preferred.Immunohistochemistry can differentiate most of the variants of PFIC but confirmation requires genetic analysis.
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Cholestatic liver disease consists of a variety of disorders.Primary sclerosing cholangitis and primary biliary cirrhosis are the most commonly recognized cholestatic liver disease in the adult population,while biliary atresia and Alagille syndrome are commonly recognized in the pediatric population.In infants,the causes are usually congenital or inherited.Even though jaundice is a hallmark of cholestasis,it is not always seen in adult patients with chronic liver disease.Patients can have"silent"progressive cholestatic liver disease for years prior to development of symptoms such as jaundice and pruritus.In this review,we will discuss some of the atypical causes of cholestatic liver disease such as benign recurrent intrahepatic cholestasis,progressive familial intrahepatic cholestasis,Alagille Syndrome,biliary atresia,total parenteral nutrition induced cholestasis and cholestasis secondary to drug induced liver injury.
基金Supported by The Department of Science and Technology of Guizhou Province,No.[2020]1Y299National Natural Science Foundation of China,No.82060123+2 种基金National Health Commission of Guizhou Province,No.gzwjk2019-1-082Doctor Start Fund of Affiliated Hospital of Guizhou Medical University,No.gyfybsky-2021-28National Natural Cultivation Fund of Affiliated Hospital of Guizhou Medical University,No.Ⅰ-2020-12.
文摘BACKGROUND Gene mutations in ATP-binding cassette,subfamily B(ABCB4)lead to autosomal recessive disorders.Primary light amyloidosis is a rare and incurable disease.Here,we report a rare case of liver cirrhosis caused by ABCB4 gene mutation combined with primary light amyloidosis.CASE SUMMARY We report a case of a 25-year-old female who was hospitalized due to recurrent abdominal pain caused by calculous cholecystitis and underwent cholecystectomy.Pathological examination of the liver tissue suggested liver cirrhosis with bile duct injury.Exon analyses of the whole genome from the patient’s peripheral blood revealed the presence of a heterozygous mutation in the ABCB4 gene.Bone marrow biopsy tissues,renal puncture examination,and liver mass spectrometry confirmed the diagnosis of a rare progressive familial intrahepatic cholestasis type 3 with systemic light chain type κ amyloidosis,which resulted in cirrhosis.Ursodeoxycholic acid and the cluster of differentiation 38 monoclonal antibody daretozumab were administered for treatment.Following treatment,the patient demonstrated significant improvement.Urinary protein became negative,peripheral blood-free light chain and urine-free light chain levels returned to normal,and the electrocardiogram showed no abnormalities.Additionally,the patient’s lower limb numbness resolved,and her condition remained stable.CONCLUSION This report presents the diagnosis and treatment of liver cirrhosis,a rare disease that is easily misdiagnosed or missed.
