Progressive familial intrahepatic cholestasis

Odevixibat and partial external biliary diversion showed equal improvement of cholestasis in a patient with progressive familial intrahepatic cholestasis

Untreated progressive familial intrahepatic cholestasis (PFIC) type 2, or bile salt exporter protein deficiency, frequently leads to severe pruritus, impaired growth and progressive liver fibrosis with risk of organ failure. We describe a 15-month-old male patient with severe pruritus diagnosed with PFIC type 2 enrolled in an open-label phase 2 study who received 4 weeks of treatment with odevixibat, an ileal bile acid transporter inhibitor under development for cholestatic liver disease treatment. The patient experienced reductions in serum bile acids and improvement in itching and sleep scores, and odevixibat was well tolerated. After the odevixibat study, symptoms returned and the patient underwent partial external biliary diversion (PEBD). Odevixibat treatment and PEBD produced similar normalisation of serum bile acid levels and improvements in pruritus and sleep disruptions. Thus, odevixibat appeared to be as effective as invasive PEBD in treating serum bile acids and cholestatic pruritus in this patient.

Phenotypic spectrum and diagnostic pitfalls of ABCB4 deficiency depending on age of onset

Genetic variants in the adenosine triphosphate-binding cassette subfamily B member 4 (ABCB4) gene, which encodes hepatocanalicular phosphatidylcholine floppase, can lead to different phenotypes, such as progressive familial intrahepatic cholestasis (PFIC) type 3, low phospholipid-associated cholelithiasis, and intrahepatic cholestasis of pregnancy. The aim of this multicenter project was to collect information on onset and progression of this entity in different age groups and to assess the relevance of this disease for the differential diagnosis of chronic liver disease. Clinical and laboratory data of 38 patients (17 males, 21 females, from 29 families) with homozygous or (compound) heterozygous ABCB4 mutations were retrospectively collected. For further analysis, patients were grouped according to the age at clinical diagnosis of ABCB4-associated liver disease into younger age (<18 years) or adult age (≥18 years). All 26 patients diagnosed in childhood presented with pruritus (median age 1 year). Hepatomegaly and splenomegaly were present in 85% and 96% of these patients, respectively, followed by jaundice (62%) and portal hypertension (69%). Initial symptoms preceded diagnosis by 1 year, and 13 patients received a liver transplant (median age 6.9 years). Of note, 9 patients were misdiagnosed as biliary atresia, Alagille syndrome, or PFIC type 1. In the 12 patients with diagnosis in adulthood, the clinical phenotype was generally less severe, including intrahepatic cholestasis of pregnancy, low phospholipid-associated cholelithiasis, or (non)cirrhotic PFIC3. Conclusion: ABCB4 deficiency with onset in younger patients caused a more severe PFIC type 3 phenotype with the need for liver transplantation in half the children. Patients with milder phenotypes are often not diagnosed before adulthood. One third of the children with PFIC type 3 were initially misdiagnosed, indicating the need for better diagnostic tools and medical education. (Hepatology Communications 2018;2:504-514).

Liver transplantation for decompensated liver cirrhosis caused by progressive familial intrahepatic cholestasis type 3: A case report

RATIONALE

Progressive familial intrahepatic cholestasis (PFIC) type 3, characterized by high gamma glutamyl transferase (GGT), is an autosomal recessive genetic disease. It often occurs in patients' first years of age. However, high GGT type PFIC is still rare.

PATIENT CONCERNS

The present study reports a case of liver transplantation for decompensated liver cirrhosis caused by PFIC type 3. An 18-year-old male presented with a history of abdominal distension and jaundice for 2 months. He had abdominal tenderness but no rebounding pain. Moreover, his dullness was felt over the liver and the spleen was palpable 8 cm below the ribs.

DIAGNOSES

Computed tomography and magnetic resonance cholangiopancreato graphy of the upper abdomen revealed cirrhosis, portal hypertension, collateral circulation formation, large spleen, and ascites. Blood biochemistry showed high alanine transaminase, aspartate transaminase, and GGT. The diagnosis of decompensated liver cirrhosis caused by PFIC-3 was finally confirmed by plasma gene detecting.

INTERVENTIONS

The patient received an open surgery named allogeneic liver transplantation after successful matching of immune types between the recipient and donor. Peritoneal puncture and catheter drainage under B-ultrasound was performed when an encapsulated effusion between the liver and stomach arose.

OUTCOMES

The patient was discharged without specific discomfort and was almost free of fluid accumulation 51 days after the surgery. At the 6-month follow-up, he had no discomfort and the blood routine, liver functions showed no abnormalities.

LESSONS

We found a new mutant fragment of ABCB4 gene in the process of diagnosis. Liver transplantation remains the most definitive treatment for PFIC. Current medical therapies and surgical interventions such as biliary diversion have potentially created a synergistic outcome.

Partial internal biliary diversion for patients with progressive familial intrahepatic cholestasis type 1

We herein report a case of progressive familial intrahepatic cholestasis with partial internal biliary diversion (PIBD). Although by using PIBD an external stoma can be avoided, exposure of the ileocecal junction to bile reflux as well as the effects of the direct bile flow on the colonic mucosa require further investigation.

Cholecystoappendicostomy for progressive familial intrahepatic cholestasis

We report a rare case of progressive familial intrahepatic cholestasis type 2 from India. The diagnosis was confirmed on the basis of gene mutation analysis. The child had intense pruritus refractory to conventional medical management. As liver biopsy did not reveal any cirrhosis, partial external biliary diversion was considered as an alternative to liver transplant. We performed cholecystoappendicostomy rather than the conventional method of using an ileal loop as a conduit between the gall bladder and abdominal wall. Child recovered completely.

DHPLC screening for mutations in progressive familial intrahepatic cholestasis patients

Progressive familial intrahepatic cholestasis (PFIC) is a group of rare heterogeneous autosomal recessive disorders characterized by metabolic defects in biliary proteins involved in the formation and transfer of bile acids in the liver. The genotype-phenotype correlation is not always clear. Mutations in the ATP8B1, BSEP and MDR3 genes have been associated with PFIC1, PFIC2 and PFIC3, respectively. This study sought to characterize the molecular genetic basis for PFIC subtypes in Israel. It was conducted on 14 children with PFIC and their families; 10 with a PFIC1 or PFIC2 phenotype and 4 with a PFIC3 phenotype. Using denaturing high-performance liquid chromatography (DHPLC), five different mutations were identified in four affected families: three novel mutations in BSEP (G19R-g181c, S226L-c803t and G877R-g2755a), one novel mutation in MDR3 (IVS14+6 t/c) and one heterozygous mutation in ATP8B1 (R600W, in a family with the PFIC1/PFIC2 phenotype). The cause of PFIC was identified in 20% of the families tested. These findings indicate the probable involvement of additional genes in PFIC and the need for further studies to determine whether the abnormality lies on the RNA or protein level. A better understanding of the phenotype-genotype correlation in PFIC will lead to improved diagnoses and treatments.

Gradual improvement of liver function after administration of ursodeoxycholic acid in an infant with a novel ABCB11 gene mutation with phenotypic continuum between BRIC2 and PFIC2

OBJECT

The authors report the case of a boy with PFIC type 2 or BRIC type 2 who suffered from liver dysfunction at 2 months after birth.

METHODS AND RESULTS

A liver biopsy specimen revealed mild liver cirrhosis, and the findings resembled those observed in Byler disease. Genetic examination revealed a normal familial intrahepatic cholestasis-1 gene, but a heterozygous mutation for the ABCB11, C1620A (F540L), was observed. Therefore, the patient was initially diagnosed with PFIC type 2. For 3 years after the diagnosis, he had severe pruritus, an increased serum bile acid, and normal serum values of gamma-glutamyl transaminase. At the age of 2, treatment with administration of ursodeoxycholic acid was started; subsequently, a gradual improvement in his liver function was observed. At the age of 3, he suffered from massive intestinal and pulmonary hemorrhage, which improved immediately after the administration of vitamin K. He was then admitted to our hospital for liver transplantation. At 1 month after the admission, his liver dysfunction showed further improvement, except for a mild increase in the serum bile acid level. This condition did not show any change during the 5-year follow-up period. In addition, the patient showed severe growth failure and was diagnosed with growth hormone deficiency. Hence, he receives growth hormone administration.

CONCLUSION

The patient could be genetically diagnosed with bile salt export pump disease of PFIC type 2 or BRIC type 2. Various clinical features are observed in PFIC or BRIC patients with ABCB11 mutation.

Partial internal biliary diversion through a cholecystojejunocolonic anastomosis--a novel surgical approach for patients with progressive familial intrahepatic cholestasis: a preliminary report

BACKGROUND/PURPOSE

The purpose of the study was to describe the initial experience with a novel approach to the surgical treatment of progressive familial intrahepatic cholestasis (PFIC), avoiding the creation of a permanent stoma.

METHODS

Two teenaged patients, aged 15 and 17 years, underwent partial internal biliary diversion to treat uncontrollable pruritus associated with PFIC. The surgical technique involved the creation of an isolated jejunal conduit, anastomosed proximally in a terminolateral fashion to the gallbladder and distally to the ascending colon. This operation combines the advantages of partially diverting the biliary flow from the enterohepatic cycle, avoiding an external biliary fistula. In one of the patients, this technique was used as a primary procedure, whereas in the other, a previous partial external diversion was converted to an internal diversion.

RESULTS

Both patients had complete resolution of their pruritus and normalization of hepatic laboratory tests. One of the patients developed a mild choleretic diarrhea that can be controlled with eventual use of cholestyramine. No complications were observed related to this operation.

CONCLUSIONS

Biliary diversion appears to be a very attractive surgical option for the treatment of PFIC in children with a normal gallbladder. Long-term follow-up is necessary to evaluate late results and eventual complications of this approach.

Exocrine pancreatic function in children with progressive familial intrahepatic cholestasis type 2

In progressive familial intrahepatic cholestasis type 2 (PFIC-2), severe steatorrhea is often documented. However, pancreatic exocrine secretion has not yet been studied. In 14 children with PFIC-2, pancreatic function was assessed using standard fecal tests. Normal fecal lipase concentrations excluded isolated lipase deficiency. No differences in fecal elastase-1 concentrations and chymotrypsin activities were detected between PFIC-2 patients with or without steatorrhea, nor between these patients and healthy subjects. In conclusion, pancreatic exocrine function in patients with PFIC-2 is normal. Steatorrhea observed in those patients is not related to pancreatic insufficiency.

Bile acids induce adhesion molecule expression in endothelial cells through activation of reactive oxygen species, NF-kappaB, and p38

Bile acids are synthesized in the liver, stored in gallbladder, and secreted into the intestine to aid in the absorption of lipid-soluble nutrients. In addition, bile acids also actively participate in regulation of gene expression through their ability to act as ligands for the nuclear receptor farnesoid X receptor or by activating kinase signaling pathways. Under cholestatic conditions, elevated levels of bile acids in the liver induce hepatic inflammation, and because bile acid levels are also elevated in the circulation, they might also induce vascular inflammation. To test this hypothesis, primary human umbilical vein endothelial cells (HUVEC) and human aortic endothelial cells were treated with bile acids, and the expression of ICAM-1, VCAM-1, and E-selectin were monitored. The three major bile acids found in the circulation, chenodeoxycholic acid, deoxycholic acid, and lithocholic acid, all strongly induced both the mRNA and protein expression of ICAM-1 and VCAM-1. To delineate the mechanism, the experiments were conducted in the presence of various kinase inhibitors. The results demonstrate that the bile acid-mediated induction of adhesion molecule expression occurs by stimulation of NF-kappaB and p38 MAPK signaling pathways through the elevation in reactive oxygen species. The bile acid-induced cell surface expression of ICAM-1 and VCAM-1 was sufficient to result in the increased adhesion of THP-1 monocytes to the HUVEC, suggesting that elevated levels of bile acids in the circulation may cause endothelium dysfunction and contribute to the initiation of early events associated with vascular lesion formation.

Clinical Characteristics and Prognosis of Pediatric Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is a rare pediatric malignancy that is usually advanced at diagnosis, with a relatively poor prognosis. Extensive treatment, including complete tumor resection, is believed to be necessary for cure. This study was performed to analyze treatment results and to search for prognostic factors of pediatric HCC.

METHODS

Between March 1982 and February 2004 a total of 16 children had been diagnosed as having HCC in our institution, and a retrospective analysis was performed.

RESULTS

The median age at diagnosis was 10.5 years, and the male/female ratio was 11:5. As a predisposing condition, hepatitis B virus (HBV) infections were present in 11 (68.8%) and liver cirrhosis in 8 (50.0%). Including 1 patient with a liver transplant, 4 patients (25.0%) underwent a primary operation with complete tumor resection, and 11 (68.8%) received neoadjuvant chemotherapy because of their inoperable state at diagnosis. After neoadjuvant chemotherapy, complete tumor resection was performed in four (36.4%). Thus complete resection was undertaken in a total of eight patients (50.0%). The estimated 5-year survival rate of all patients was 27.3%. The 5-year survival rate for patients who underwent complete tumor resection was 62.5%, and for those who underwent palliative resection or no operation it was 0%. The statistically significant prognostic factors were tumor stage, presence of metastasis, and complete tumor resection.

CONCLUSIONS

This study confirmed that complete tumor resection is essential for cure in pediatric patients with HCC, and neoadjuvant chemotherapy improves the tumors' resectability.

Evaluation of risk for atherosclerosis in Alagille syndrome and progressive familial intrahepatic cholestasis: two congenital cholestatic diseases with different lipoprotein metabolisms

OBJECTIVES

To evaluate the risk for atherosclerosis in Alagille syndrome (AGS) and progressive familial intrahepatic cholestasis (PFIC) on the basis of lipoprotein metabolism and by ultrasonography.

STUDY DESIGN

Five patients with AGS and 5 with PFIC, ages 3 to 4 years, were enrolled. Intimal-medial thickness and wall stiffness of the common carotid artery were examined by ultrasonography. Serum levels of lipids and lipoproteins were determined. Further, the chemical composition of LDL and its ability to transform macrophages into foam cells were determined.

RESULTS

Intimal-medial thickness and wall stiffness were increased in patients with PFIC but not in patients with AGS. Total cholesterol, LDL cholesterol, HDL cholesterol, and lipoprotein X were remarkably increased in patients with AGS, whereas in patients with PFIC, an increase in triglyceride and a decrease in HDL cholesterol were the prominent findings. However, despite the normal LDL cholesterol level, oxidized LDL level was strikingly high in patients with PFIC. LDLs from patients with PFIC had high TG contents and exhibited high abilities to transform macrophages into foam cells.

CONCLUSIONS

These findings suggest that patients with PFIC are at high risk for cardiovascular disorders involving atherosclerosis.

Living related liver transplantation in 13 cases of progressive familial intrahepatic cholestasis

Progressive familial intrahepatic cholestasis (PFIC) is a heterogenous group of disorders with various etiologies. Recent molecular and genetic studies have categorized the spectrum of types. Liver transplantation is a curative modality of treatment in this disease. We report our experience with 13 patients with PFIC who underwent living related liver transplantation. The follow-up periods ranged from 12 to 50 months. Two children died at 1 and 2 years posttransplantation, leading to a decrease in survival rate from 100% in the first year to 84.6%.

Molecular basis of neonatal cholestasis

At present, specific evidence regarding the molecular mechanisms of neonatal cholestasis is limited. The recent explosion in the understanding of the molecular physiology of bile formation has been fueled by the discovery of several genes that are involved in familial cholestasis. The ever-growing understanding of the functional immaturity of the neonatal liver is sure to be enhanced by the study of the ontogeny of important hepatobiliary transporters as they are discovered. The understanding of the functional differences between the immature and mature liver is key to the understanding of neonatal cholestasis.

Transport of bile acids in hepatic and non-hepatic tissues

Bile acids are steroidal amphipathic molecules derived from the catabolism of cholesterol. They modulate bile flow and lipid secretion, are essential for the absorption of dietary fats and vitamins, and have been implicated in the regulation of all the key enzymes involved in cholesterol homeostasis. Bile acids recirculate through the liver, bile ducts, small intestine and portal vein to form an enterohepatic circuit. They exist as anions at physiological pH and, consequently, require a carrier for transport across the membranes of the enterohepatic tissues. Individual bile acid carriers have now been cloned from several species. Na(+)-dependent transporters that mediate uptake into hepatocytes and reabsorption from the intestine and biliary epithelium and an ATP-dependent transporter that pumps bile acids into bile comprise the classes of transporter that are specific for bile acids. In addition, at least four human and five rat genes that code for Na(+)-independent organic anion carriers with broad multi-substrate specificities that include bile acids have been discovered. Studies concerning the regulation of these carriers have permitted identification of molecular signals that dictate eventual changes in the uptake or excretion of bile acids, which in turn have profound physiological implications. This overview summarizes and compares all known bile acid transporters and highlights findings that have identified diseases linked to molecular defects in these carriers. Recent advances that have fostered a more complete appreciation for the elaborate disposition of bile acids in humans are emphasized.

Progressive familial intrahepatic cholestasis: partial biliary diversion normalizes serum lipids and improves growth in noncirrhotic patients

OBJECTIVES

Progressive familial intrahepatic cholestasis (PFIC) usually presents with pruritus, jaundice, hepatomegaly, and growth failure. A group of PFIC is recognized by marked elevation of total serum bile acids, decreased serum apolipoprotein A-1, and high-density lipoprotein, but normal gamma-glutamyltranspeptidase and cholesterol. Although medical therapy generally fails, partial external biliary diversion (DIV) has been used with promising results for cholestasis. However, little has been reported of its effect on linear growth, synthetic liver function, and lipid metabolism.

METHODS

DIV was performed on six noncirrhotic children with PFIC, all suffering from severe pruritus and cholestasis, refractory to medical treatment. Stature was below -1 (median, -2.3) standard deviation score (SDS) for height in all cases. All patients had markedly enhanced bile acids (307 +/- 72 microl/L), markedly decreased high-density lipoprotein (20 +/- 7 mg/dl), and apolipoprotein A-1 (58 +/- 37 mg/dl), but normal gamma-glutamyltranspeptidase and cholesterol. In addition, cholinesterase activity, monoethylglycinexylidide test, and Fischer's ratio indicated a significantly reduced synthetic liver function in all children but the youngest.

RESULTS

After DIV, all patients were consistently relieved of pruritus, and experienced normalization of all liver function tests, including cholinesterase activity, monoethylglycinexylidide test, and Fischer's ratio, as well as the serum lipid profile within 1 yr. In addition, a marked catch-up growth (median, +/- 1.3 SDS) was evident after 1 yr in all cases.

CONCLUSIONS

This report shows an excellent result of DIV in noncirrhotic PFIC patients and compares favorably with other reports. All patients experienced complete remission, including normalization of synthetic liver function and lipid metabolism. For the first time we have shown that DIV can also be associated with an accelerated growth in these patients.

Progressive familial intrahepatic cholestasis. Genetic basis and treatment

Major advances in the understanding of the molecular mechanisms of bile formation and genetic studies of children with chronic cholestasis uncovered the molecular basis of PFIC. Specific defects in the FIC1, BSEP, and MDR3 genes are responsible for distinct PFIC phenotypes. These findings have confirmed the autosomal recessive inheritance of the disease and now provide specific diagnostic tools for the investigation of children with PFIC. This understanding should also allow prenatal diagnosis in the future. Identification of mutations in these genes will allow genotype-phenotype correlations to be defined within the spectrum of PFIC. These correlations performed in patients previously treated by UDCA or biliary diversion should identify those PFIC patients who could benefit from these therapies. In the future, other therapies, such as cell and gene therapies, might represent an alternative to liver transplantation. It remains to be determined if defects in the FIC1, BSEP, and MDR3 genes are responsible for all types of PFIC, or if other yet undiscovered genes, possibly involved in bile formation or its regulation, may be involved in the pathogenesis of PFIC.

Current status of pediatric liver transplantation

Increased survival for young liver transplant recipients has greatly improved. Increasing success has led to broader indications, thereby increasing the number of potential recipients. Pediatric liver centers are developing new strategies to cope with the ever-increasing demands for suitable size appropriate grafts. UNOS is in the process of updating guidelines to regulate the sharing of organs which become available from new surgical techniques. In the future, alternative therapies, such as artificial liver assist devices and techniques of cellular transplantation and genetic modification of hepatocytes, may decrease the number of children who die while waiting for a suitable organ or even obviate the need for the liver transplantation.