Liver transplantation for progressive familial intrahepatic cholestasis: clinical and histopathological findings, outcome and impact on growth

Emerging drugs for the treatment of progressive familial intrahepatic cholestasis: a focus on phase II and III trials

INTRODUCTION

Progressive familial intrahepatic cholestasis (PFIC) is a group of disorders characterized by inappropriate bile formation, causing hepatic accumulation of bile acids and, subsequently, liver injury. Until recently, no approved treatments were available for these patients.

AREAS COVERED

Recent clinical trials for PFIC treatment have focused on intestine-restricted ileal bile acid transporter (IBAT) inhibitors. These compounds aim to reduce the pool size of bile acids by interrupting their enterohepatic circulation. Other emerging treatments in the pipeline include systemic IBAT inhibitors, synthetic bile acid derivatives, compounds targeting bile acid synthesis via the FXR/FGF axis, and chaperones/potentiators that aim to enhance the residual activity of the mutated transporters.

EXPERT OPINION

Substantial progress has been made in drug development for PFIC patients during the last couple of years. Although data concerning long-term efficacy are as yet only scarcely available, new therapies have demonstrated robust efficacy in a considerable fraction of patients at least on the shorter term. However, a substantial fraction of PFIC patients do not respond to these novel therapies and thus still requires surgical treatment, including liver transplantation before adulthood. Hence, there is still an unmet medical need for long-term effective medical, preferably non-surgical, treatment for all PFIC patients.

Novel Gene-Correction-Based Therapeutic Modalities for Monogenic Liver Disorders

The majority of monogenic liver diseases are autosomal recessive disorders, with few being sex-related or co-dominant. Although orthotopic liver transplantation (LT) is currently the sole therapeutic option for end-stage patients, such an invasive surgical approach is severely restricted by the lack of donors and post-transplant complications, mainly associated with life-long immunosuppressive regimens. Therefore, the last decade has witnessed efforts for innovative cellular or gene-based therapeutic strategies. Gene therapy is a promising approach for treatment of many hereditary disorders, such as monogenic inborn errors. The liver is an organ characterized by unique features, making it an attractive target for in vivo and ex vivo gene transfer. The current genetic approaches for hereditary liver diseases are mediated by viral or non-viral vectors, with promising results generated by gene-editing tools, such as CRISPR-Cas9 technology. Despite massive progress in experimental gene-correction technologies, limitations in validated approaches for monogenic liver disorders have encouraged researchers to refine promising gene therapy protocols. Herein, we highlighted the most common monogenetic liver disorders, followed by proposed genetic engineering approaches, offered as promising therapeutic modalities.

Long-Term Results of Pediatric Liver Transplantation for Progressive Familial Intrahepatic Cholestasis

We analyzed the long-term survival rate and development of progressive familial intrahepatic cholestasis (PFIC) patients after liver transplantation (LT). From October 2007 to May 2019, 41 patients were diagnosed as PFIC (type I-III) and received LT in Ren Ji Hospital due to end-stage liver diseases. The median age at LT was 2.93 years, with 75.6% of patients receiving living donor liver transplantation (LDLT). The 5- and 10-year patient survival rates after LT were 92.7% and 92.7%, respectively, and no difference was found among the three subtypes of PFIC. Two PFIC type II patients received re-transplantation due to vascular complications. Liver function and bile acid metabolism returned to normal levels in all living recipients. Catch-up growth was recorded as the height and weight Z scores increased from −2.53 and −1.54 to −0.55 and −0.27 with a median follow-up time of 5.55 years. Improved psychomotor ability and age-appropriate study ability was also observed. A total of 72.4% of school-aged recipients exhibited average academic performance. Diarrhea was reported in all PFIC type I recipients but resolved after resin absorptive treatment. However, allograft steatosis occurred in one PFIC type I patient and exhibited a “remission–relapse circle” under the treatment of cholestyramine. In conclusion, LT is an effective treatment for end-stage PFIC patients with encouraging long-term survival rate and development. However, allograft steatosis should be closely monitored in PFIC type I patients even if diarrhea has been well treated.

18β-Glycyrrhetinic Acid Protects against Cholestatic Liver Injury in Bile Duct-Ligated Rats

18β-Glycyrrhetinic acid is a nutraceutical agent with promising hepatoprotective effects. Its protective mechanisms against cholestatic liver injury were further investigated in a rodent model of extrahepatic cholestasis caused by Bile Duct Ligation (BDL) in rats. The daily oral administration of 18β-Glycyrrhetinic acid improved liver histology, serum biochemicals, ductular reaction, oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis. 18β-Glycyrrhetinic acid alleviated the BDL-induced hepatic and systemic retention of bile acids, matrix-producing cell activation, hepatic collagen deposition, Transforming Growth Factor beta-1/Smad activation, malondialdehyde elevation, glutathione reduction, High Mobility Group Box-1/Toll-Like Receptor-4 activation, NF-κB activation, inflammatory cell infiltration/accumulation, Interleukin-1β expression, Signal Transducer and Activator of Transcription-1 activation, Endoplasmic Reticulum stress, impairment autophagy, and caspase 3 activation. Conversely, the protein expression of Sirt1, Farnesoid X Receptor, nuclear NF-E2-Related Factor-2, Transcription Factor EB, bile acid efflux transporters, and LC3-II, as well as the protein phosphorylation of AMP-Activated Protein Kinase, was promoted in 18β-Glycyrrhetinic acid-treated BDL rats. The hepatoprotective effects of 18β-Glycyrrhetinic acid in the present investigation correlated well with co-activation and possible interactions among Sirt, FXR, and Nrf2. The concurrent or concomitant activation of Sirt1, FXR, and Nrf2 not only restored the homeostatic regulation of bile acid metabolism, but also alleviated oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis.

Living donor liver transplantation in an infant patient with progressive familial intrahepatic cholestasis along with hepatocellular carcinoma: a case report

Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease requiring liver transplantation (LT). Hepatocellular carcinoma (HCC) is very rare in infants. We present a case of living donor LT using a left lateral section graft performed in a 7-month-old female infant diagnosed with PFIC type II and HCC. No mutation on ABCB11 gene was identified. Because of progressive deterioration of liver function, living donor LT with her mother's left lateral section graft was performed. Pretransplant serum alpha-fetoprotein (AFP) level was increased to 2,740 ng/mL, but HCC was not taken into account because of its rarity. The explant liver showed micronodular liver cirrhosis, multiple infantile hemangiomas and two HCCs of 0.7 cm and 0.3 cm in size. The patient recovered uneventfully from the LT operation. This patient has been regularly followed up with abdomen ultrasonography and AFP measurement every 6 months. The patient has been continually doing well for 8 years after the LT. In conclusion, LT is currently the only effective treatment for PFIC-associated end-stage liver diseases. HCC can develop at the cirrhotic liver of any cause, thus elevation of HCC tumor markers in pediatric patients is an important clue to perform further investigation before LT.

Recent updates on progressive familial intrahepatic cholestasis types 1, 2 and 3: Outcome and therapeutic strategies

Recent evidence points towards the role of genotype to understand the phenotype, predict the natural course and long term outcome of patients with progressive familial intrahepatic cholestasis (PFIC). Expanded role of the heterozygous transporter defects presenting late needs to be suspected and identified. Treatment of pruritus, nutritional rehabilitation, prevention of fibrosis progression and liver transplantation (LT) in those with end stage liver disease form the crux of the treatment. LT in PFIC has its own unique issues like high rates of intractable diarrhoea, growth failure; steatohepatitis and graft failure in PFIC1 and antibody-mediated bile salt export pump deficiency in PFIC2. Drugs inhibiting apical sodium-dependent bile transporter and adenovirus-associated vector mediated gene therapy hold promise for future.

Liver transplantation in pediatric patients with progressive familial intrahepatic cholestasis: Single center experience of seven cases

Backgrounds/Aims

Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease requiring liver transplantation (LT). The objective of this study was to investigate the clinicopathological features and posttransplant courses of seven LT recipients with PFIC.

Methods

This was a retrospective single-center study of patients with PFIC who underwent LT from January 2013 to June 2020.

Results

Two and five patients were diagnosed with PFIC type 1 and type 2, respectively. For all seven patients, age of PFIC onset was at birth. Jaundice was present in all cases. Mean pretransplant total and direct bilirubin levels were 16.1 ± 8.1 mg/dL and 12.4 ± 6.2 mg/dL, respectively. Median patient age and body weight at LT were 10 months and 7 kg, respectively. Types of donors were mothers of patients in four and deceased donors in three. All five patients with PFIC type 2 recovered uneventfully. One patient each with PFIC type 1 underwent retransplantation due to graft failure or died due to multi-organ failure. Overall graft and patient survival rates at five years were 66.7% and 83.3%, respectively. Bile salt export pump immunohistochemical staining showed normal canalicular expression in two patients with PFIC type 1, focal loss in two patients with PFIC type 2, and total loss in three patients with PFIC type 2.

Conclusions

LT is currently the only effective treatment for PFIC-associated end-stage liver diseases. It is mandatory to perform regular follow-up due to the risk of complications including steatohepatitis, especially for patients with PFIC type 1.

Long-term liver transplant outcomes for progressive familial intrahepatic cholestasis type 1: The Pittsburgh experience

BACKGROUND

Progressive familial intrahepatic cholestasis type 1 (PFIC1) arises from biallelic variants in the ATP8B1 gene that annul FIC1 activity, resulting in progressive liver disease. Liver transplant (LT) is indicated in refractory disease; however, post-LT complications including worsening diarrhea and steatohepatitis progressing to fibrosis with graft loss have been reported. We aim to describe long-term outcomes of PFIC1 LT recipients at our center, focusing on the histological changes of the allografts.

METHODS

We assessed 7 PFIC1 patients post-LT at the Children's Hospital of Pittsburgh (CHP). All pre-transplant, explant, and sequential post-transplant pathology samples were reviewed. Continuous data are presented as the mean ± SD. We compared the pre- and post-transplant height and weight z-scores using Wilcoxon signed-rank test.

RESULTS

Seven (29% male) patients with PFIC1 received a LT (n = 6) or had post-LT care (n = 1) at CHP. Six had confirmed or suspected identical genetic. At a mean follow-up of 10.9 years, both patient survival and graft survival were 100%. Diarrhea persisted (n = 3) or newly developed (n = 4) in all patients after LT contributing to ongoing growth failure, with mean z-scores -2.63 (weight) and -2.98 (height) at follow-up. Histologically, allograft steatosis was common but was not accompanied by significant inflammation, ballooning, or fibrosis.

CONCLUSION

We show that extrahepatic disease persists and near-universal allograft steatosis occurs. However, at a mean follow-up period of over 10 years, no patients developed steatohepatitis or significant fibrosis, and both patient survival and graft survival are excellent.

Liver Transplantation in Progressive Familial Intrahepatic Cholestasis with Normal Gamma-Glutamyl Transferase: Evaluation of Post-transplant Steatosis and Steatohepatitis

Background: Progressive familial intrahepatic cholestasis is a disease presenting with severe cholestasis and progressing to the end-stage liver disease later. Liver transplantation is a treatment modality available for progressive familial intrahepatic cholestasis, especially in patients with end-stage liver disease or those who are unsuitable for or have failed biliary diversion. Objectives: To evaluate clinical and pathological characteristics of progressive familial intrahepatic cholestasis patients who had undergone liver transplantation and to determine post-transplant steatosis and steatohepatitis. Methods: We evaluated 111 progressive familial intrahepatic cholestasis patients with normal gamma-glutamyl transferase that performed liver transplantation in Shiraz Transplant Center in Iran between March 2000 and March 2017. Results: The most common clinical manifestations were jaundice and pruritus. Growth retardation and diarrhea were detected in 76.6% and 42.5% of the patients. After transplantation, growth retardation was seen in 31.5% of the patients, and diarrhea in 36.9% of them. Besides, 29.1% of the patients died post-transplant. Post-transplant liver biopsies were taken from 50 patients, and 15 (30%) patients had steatosis or steatohepatitis, five of whom (10%) had macrovesicular steatosis alone, and 10 (20%) had steatohepatitis. Only one patient showed moderate bridging fibrosis (stage III), and none of them showed severe fibrosis. Conclusions: Liver transplantation is the final treatment option for these patients, and it can relieve most clinical manifestations. However, post-transplant mortality rate was relatively high in our center. Diarrhea, growth retardation, and steatosis are unique post-transplant complications in these patients. The rate of post-transplant steatosis and steatohepatitis in patients with liver biopsy in our study was 30%, with a significant difference from previous studies.

Long-Term Outcome after Liver Transplantation for Progressive Familial Intrahepatic Cholestasis

Background and Objectives: Progressive familial intrahepatic cholestasis (PFIC) is a rare autosomal recessive inherited disease divided into five types (PFIC 1-5). Characteristic for all types is early disease onset, which may result clinically in portal hypertension, fibrosis, cirrhosis, hepatocellular carcinoma (HCC), and extrahepatic manifestations. Liver transplantation (LT) is the only successful treatment approach. Our aim is to present the good long-term outcomes after liver transplantation for PFIC1, focusing on liver function as well as the occurrence of extrahepatic manifestation after liver transplantation. Materials and Methods: A total of seven pediatric patients with PFIC1 underwent liver transplantation between January 1999 and September 2019 at the Department of Surgery, Charité Campus Virchow Klinikum and Charité Campus Mitte of Charité-Universitätsmedizin Berlin. Long-term follow-up data were collected on all patients, specifically considering liver function and extrahepatic manifestations. Results: Seven (3.2%) recipients were found from a cohort of 219 pediatric patients. Two of the seven patients had multilocular HCC in cirrhosis. Disease recurrence or graft loss did not occur in any patient. Two patients (male, siblings) had persistently elevated liver parameters but showed excellent liver function. Patient and graft survival during long-term follow-up was 100%, and no severe extrahepatic manifestations requiring hospitalization or surgery occurred. We noted a low complication rate during long-term follow-up and excellent patient outcome. Conclusions: PFIC1 long-term follow-up after LT shows promising results for this rare disease. In particular, the clinical relevance of extrahepatic manifestations seems acceptable, and graft function seems to be barely affected. Further multicenter studies are needed to analyze the clinically inhomogeneous presentation and to better understand the courses after LT.

Impact of Genotype, Serum Bile Acids, and Surgical Biliary Diversion on Native Liver Survival in FIC1 Deficiency

BACKGROUND AND AIMS

Mutations in ATPase phospholipid transporting 8B1 (ATP8B1) can lead to familial intrahepatic cholestasis type 1 (FIC1) deficiency, or progressive familial intrahepatic cholestasis type 1. The rarity of FIC1 deficiency has largely prevented a detailed analysis of its natural history, effects of predicted protein truncating mutations (PPTMs), and possible associations of serum bile acid (sBA) concentrations and surgical biliary diversion (SBD) with long-term outcome. We aimed to provide insights by using the largest genetically defined cohort of patients with FIC1 deficiency to date.

APPROACH AND RESULTS

This multicenter, combined retrospective and prospective study included 130 patients with compound heterozygous or homozygous predicted pathogenic ATP8B1 variants. Patients were categorized according to the number of PPTMs (i.e., splice site, frameshift due to deletion or insertion, nonsense, duplication), FIC1-A (n = 67; no PPTMs), FIC1-B (n = 29; one PPTM), or FIC1-C (n = 34; two PPTMs). Survival analysis showed an overall native liver survival (NLS) of 44% at age 18 years. NLS was comparable among FIC1-A, FIC1-B, and FIC1-C (% NLS at age 10 years: 67%, 41%, and 59%, respectively; P = 0.12), despite FIC1-C undergoing SBD less often (% SBD at age 10 years: 65%, 57%, and 45%, respectively; P = 0.03). sBAs at presentation were negatively associated with NLS (NLS at age 10 years, sBAs < 194 µmol/L: 49% vs. sBAs ≥ 194 µmol/L: 15%; P = 0.03). SBD decreased sBAs (230 [125-282] to 74 [11-177] μmol/L; P = 0.005). SBD (HR 0.55, 95% CI 0.28-1.03, P = 0.06) and post-SBD sBA concentrations < 65 μmol/L (P = 0.05) tended to be associated with improved NLS.

CONCLUSIONS

Less than half of patients with FIC1 deficiency reach adulthood with native liver. The number of PPTMs did not associate with the natural history or prognosis of FIC1 deficiency. sBA concentrations at initial presentation and after SBD provide limited prognostic information on long-term NLS.

Epidemiology and burden of progressive familial intrahepatic cholestasis: a systematic review

Background

Progressive familial intrahepatic cholestasis is a rare, heterogeneous group of liver disorders of autosomal recessive inheritance, characterised by an early onset of cholestasis with pruritus and malabsorption, which rapidly progresses, eventually culminating in liver failure. For children and their parents, PFIC is an extremely distressing disease. Significant pruritus can lead to severe cutaneous mutilation and may affect many activities of daily living through loss of sleep, irritability, poor attention, and impaired school performance.

Methods

Databases including MEDLINE and Embase were searched for publications on PFIC prevalence, incidence or natural history, and the economic burden or health-related quality of life of patients with PFIC. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

Results

Three systematic reviews and twenty-two studies were eligible for inclusion for the epidemiology of PFIC including a total of 2603 patients. Study periods ranged from 3 to 33 years. Local population prevalence of PFIC was reported in three studies, ranging from 9.0 to 12.0% of children admitted with cholestasis, acute liver failure, or splenomegaly. The most detailed data come from the NAPPED study where native liver survival of >15 years is predicted in PFIC2 patients with a serum bile  acid concentration below 102 µmol/L following bile diversion surgery. Burden of disease was mainly reported through health-related quality of life (HRQL), rates of surgery and survival. Rates of biliary diversion and liver transplant varied widely depending on study period, sample size and PFIC type, with many patients have multiple surgeries and progressing to liver transplant. This renders data unsuitable for comparison.

Conclusion

Using robust and transparent methods, this systematic review summarises our current knowledge of PFIC. The epidemiological overview is highly mixed and dependent on presentation and PFIC subtype. Only two studies reported HRQL and mortality results were variable across different subtypes. Lack of data and extensive heterogeneity severely limit understanding across this disease area, particularly variation around and within subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01884-4.

Structure and Function of Hepatobiliary ATP Binding Cassette Transporters

The liver is beyond any doubt the most important metabolic organ of the human body. This function requires an intensive crosstalk within liver cellular structures, but also with other organs. Membrane transport proteins are therefore of upmost importance as they represent the sensors and mediators that shuttle signals from outside to the inside of liver cells and/or vice versa. In this review, we summarize the known literature of liver transport proteins with a clear emphasis on functional and structural information on ATP binding cassette (ABC) transporters, which are expressed in the human liver. These primary active membrane transporters form one of the largest families of membrane proteins. In the liver, they play an essential role in for example bile formation or xenobiotic export. Our review provides a state of the art and comprehensive summary of the current knowledge of hepatobiliary ABC transporters. Clearly, our knowledge has improved with a breath-taking speed over the last few years and will expand further. Thus, this review will provide the status quo and will lay the foundation for new and exciting avenues in liver membrane transporter research.

Novel ATP8B1 Gene Mutations in a Child with Progressive Familial Intrahepatic Cholestasis Type 1

Progressive familial intrahepatic cholestasis (PFIC) is a group of severe genetic disorders, inherited in an autosomal recessive manner, causing cholestasis of hepatocellular origin, later progressing to biliary cirrhosis and liver failure. This is the first report of PFIC type 1 with novel compound heterozygous mutations in Korea. The patient was presented with intrahepatic cholestasis, a normal level of serum γ-glutamyl transferase, steatorrhea, and growth failure. Genetic testing of this patient revealed novel compound heterozygous mutations (p.Glu585Ter and p.Leu749Pro) in the ATP8B1 gene. After a liver transplantation at age 19 months, the patient developed severe post-transplant steatohepatitis.

Reversal of secondary protein-losing enteropathy after surgical revision of a jejunal Roux-en-Y loop in a patient after liver transplantation

Secondary protein-losing enteropathy (PLE) is a rare complication following pediatric liver transplantation (LT), mostly related to venous outflow obstruction of the liver. Here, we discuss a thus far unknown cause of secondary PLE following pediatric LT. A 7-month-old boy underwent LT with biliary anastomosis using a Roux-en-Y jejunal loop. Eleven months later he developed PLE. Routine diagnostic workup was negative. No hepatic outflow obstruction was detected during catheterization. Although the hepatic venous pressure gradient was slightly increased (10 mm Hg), there were no clinical signs of portal hypertension. Albumin scintigraphy with specific early recordings suggested focal albumin intestinal entry in the jejunal Roux-en-Y loop. Local bacterial overgrowth or local lymphangiectasia, possibly due to (venous) congestion, was considered. Treatment with metronidazole did not improve albumin loss. Next, surgical revision of the jejunal Roux-en-Y loop was performed. The explanted loop contained a small abnormal area with a thin hyperemic mucosa, near the former anastomosis. Histopathological analysis showed changes both in the blood vessels and the lymphatic vessels with focal deeper chronic active inflammation resulting in congestion of vessels, hampering lymphatic outflow leading to lymphangiectasia and patchy distortion of lymphatic vessels. Following surgical revision, secondary PLE disappeared, up to now, 1.5 year post revision.

Progressive Familial Intrahepatic Cholestasis in Korea: A Clinicopathological Study of Five Patients

BACKGROUND

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous group of autosomal recessive liver diseases that present as neonatal cholestasis. Little is known of this disease in Korea.

METHODS

The records of five patients histologically diagnosed with PFIC, one with PFIC1 and four with PFIC2, by liver biopsy or transplant were reviewed, and ATP8B1 and ABCB11 mutation status was analyzed by direct DNA sequencing. Clinicopathological characteristics were correlated with genetic mutations.

RESULTS

The first symptom in all patients was jaundice. Histologically, lobular cholestasis with bile plugs was the main finding in all patients, whereas diffuse or periportal cholestasis was identified only in patients with PFIC2. Giant cells and ballooning of hepatocytes were observed in three and three patients with PFIC2, respectively, but not in the patient with PFIC1. Immunostaining showed total loss of bile salt export pump in two patients with PFIC2 and focal loss in two. Lobular and portal based fibrosis were more advanced in PFIC2 than in PFIC1. ATP8B1 and ABCB11 mutations were identified in one PFIC1 and two PFIC2 patients, respectively. One PFIC1 and three PFIC2 patients underwent liver transplantation (LT). At age 7 months, one PFIC2 patient was diagnosed with concurrent hepatocellular carcinoma and infantile hemangioma in an explanted liver. The patient with PFIC1 developed steatohepatitis after LT. One patient showed recurrence of PFIC2 after 10 years and underwent LT.

CONCLUSIONS

PFIC is not rare in patients with neonatal cholestasis of unknown origin. Proper clinicopathologic correlation and genetic testing can enable early detection and management.

Long-term outcomes after cholecystocolostomy for progressive familial intrahepatic cholestasis

AIM

To evaluate the long-term efficacy of cholecystocolostomy surgery for progressive familial intrahepatic cholestasis (PFIC).

METHODS

From August 2003 to November 2014, 34 clinically diagnosed children, including 11 with familial intrahepatic cholestasis-1 (FIC1), 13 with bile salt export pump (BSEP) disease, five with low γ-glutamyl transpeptidase (GGT) disease (levels <100 U/L), and five with multidrug resistance class III (MDR3) disease with high GGT (>100 U/L), were identified in our center. Data were collected retrospectively from individuals who collectively had 36 surgical operations and two orthotopic liver transplantations (OLT).

RESULTS

Serum total bilirubin (0 = 163.54 ± 106.02, 36 months = 23.38 ± 17.66 μmol/L) and bile acid (0 = 325.83 ± 153.09, 36 months = 48.36 ± 79.71 μmol/L) decreased after cholecystocolostomy in PFIC patients (P < 0.001). All patients experienced decreased severity of pruritus (88.2% vs. 16.1%, P < 0.001) and a greater freedom from growth retardation after cholecystocolostomy (-3.35 vs. -1.03, P < 0.001). Defecation frequency increased in PFIC patients after cholecystocolostomy (P = 0.002). Four patients (three with FIC1 and one with BSEP) experienced recurrence of cholestasis and two underwent reoperation. Two BSEP patients underwent OLT. One patient with BSEP and one patient with MDR3 died due to severe diarrhea and dehydration; one BSEP patient died of intractable constipation.

CONCLUSIONS

This is the first long-term, large-scale analysis of cholecystocolostomy approaches for PFIC. Approaches single and well tolerated, and generally result in improvement of pruritus and cholestasis.

Quality of Life in Patients With Progressive Familial Intrahepatic Cholestasis: No Difference Between Post-liver Transplantation and Post-partial External Biliary Diversion

OBJECTIVES

In patients with progressive familial intrahepatic cholestasis (PFIC), partial external biliary diversion (PEBD), which is associated with a permanent stoma, is recommended as first-line therapy, whereas primary liver transplantation (LTx) is restricted to those with cirrhosis. Our aim was to quantify the health-related quality of life (HRQOL) in patients with PFIC and to evaluate whether there is a difference in their HRQOL depending on the surgical approach.

METHODS

A prospective HRQOL study on a consecutive series of PFIC was conducted using Pediatric Quality of Life Inventory 4.0 child-self and parent-proxy reports. Patients with PFIC after PEBD who still lived with their native livers were compared to those after LTx. Both groups were compared to healthy children.

RESULTS

A total of 32 patients (53% girls) patients with a mean age of 17.7 ± 7.3 years were studied. Twenty-two had undergone LTx at a mean age of 7.8 ± 3.8 years and 10 had undergone PEBD at a mean age of 4.1 ± 3.9 years. At the time of HRQOL assessment, the mean age was 18.9 ± 7.5 years in the LTx group and 15.3 ± 6.5 years in the PEBD group. Child-self and parent-proxy reports showed no significant difference in HRQOL between patients with PFIC after LTx and those after PEBD except for marginal difference in physical functioning/health (P = 0.07). Except for a lower score in patient school functioning of patients after LTx (P = 0.01), HRQOL-results showed no difference from healthy children in any group.

CONCLUSIONS

The HRQOL of patients with PFIC after PEBD was similar to those after LTx. The HRQOL in both groups was also similar to that of healthy children. Thus, our data support the current policy of PEBD as primary surgical treatment for patients with PFIC without cirrhosis.

Liver Transplantation for Progressive Familial Intrahepatic Cholestasis

BACKGROUND Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease that disrupts the genes for bile formation. Liver transplantation (LT) is the only effective treatment for PFIC patients with end-stage liver disease. We describe our experience in terms of clinical characteristics, complications, and outcome of LT for PFIC. CASE REPORT The data of 5 pediatric PFIC patients recipients (3 PFIC1, 1 PFIC2, and 1 PFIC3) who received LT at our Liver Transplant Center from June 2013 to February 2017 were retrospectively analyzed. Four patients received liver transplantation from donation after cardiac death (DCD) donors. One patient received a living donor liver transplantation (LDLT). All the LT recipients received an immunosuppressive regimen of tacrolimus (FK 506) + methylprednisolone + mycophenolate mofetil (MMF). Diarrhea did not improve in 2 PFIC1 patients after LT, and they both developed steatohepatitis several months after LT. The other PFIC1 patient received ABO blood group incompatible LT and developed biliary complications and a severe Epstein-Barr virus infection; this patient underwent endoscopic retrograde cholangiopancreatography. She recovered after treatment with ganciclovir and reduction of tacrolimus dosage. The PFIC2 patient had abnormal liver function 19 months after LT, and recovered after administration of increased dosage of immunosuppressant agents. Liver function in the PFIC3 patient was normal during 2-year follow-up. CONCLUSIONS Liver transplantation is an effective treatment in PFIC patients. However, PFIC1 patients may develop aggravated diarrhea and steatohepatitis after LT. PFIC2 and PFIC3 patients have good outcomes after LT.

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).

Cholestasis After Pediatric Liver Transplantation-Recurrence of a Progressive Familial Intrahepatic Cholestasis Phenotype as a Rare Differential Diagnosis: A Case Report

INTRODUCTION

Nonobstructive cholestasis after pediatric liver transplantation is a common diagnostic and therapeutic dilemma. We describe a girl with neonatal cholestasis because of progressive familial intrahepatic cholestasis 2 (PFIC-2) and presence of a homozygous splice site mutation in the ABCB11 gene. Liver transplantation was performed because of end-stage liver disease at the age of 6. Cholestasis with normal gamma-glutamyl transferase (GGT) developed 8 years after liver transplantation. A liver biopsy showed canalicular cholestasis and giant cell hepatitis without evidence of rejection, mimicking PFIC-2. Immunofluorescence staining of normal human liver sections with patient's serum revealed reactivity toward a canalicular epitope, which could be identified as bile salt export pump (BSEP) using BSEP-yellow fluorescent protein (YFP) transfected cells. Our patient developed a recurrence of a PFIC-2 phenotype due to production of antibodies against BSEP (alloimmune BSEP disease [AIBD]). Intensification of immunosuppressive therapy as well as antibody treatment with plasmapheresis and Rituximab were initiated, leading to stabilization of the clinical condition and depletion of anti-BSEP antibodies in serum. However, after 1 year liver transplantation was necessary again because of end-stage liver insufficiency. Afterward, immunomodulatory treatment consisted of tacrolimus, mycophenolate mofetil, prednisone, immunoadsorption, and high-dose immunoglobulin therapy (1 g/kg/d).

CONCLUSION

Cholestasis after liver transplantation may indicate an AIBD with a PFIC-2 phenotype. Besides enhancement of immunosuppressive therapy, an antibody depletion with plasmapheresis, immunoadsorption, immunoglobulins, and B-cell depletion represents a therapeutic option.

Long-term Follow-up After Pediatric Liver Transplantation: Predictors of Growth

OBJECTIVES

The aim of the study was to describe long-term growth postpediatric liver transplantation and to conduct bivariate and multivariate analysis of factors that may predict post-transplantation growth in children who received a liver transplant from January 1999 to December 2008 at the Hospital for Sick Children.

METHODS

A retrospective cohort study was conducted with follow-up of up-to 10 years post-transplantation. Mean height and weight z scores and annual differences in mean z scores were plotted against time after transplantation. A 1-way analysis of variance was conducted. Multivariate and univariate Cox proportional hazards analyses were conducted to determine factors associated with reaching the 50th and 25th percentiles for height.

RESULTS

A total of 127 children met eligibility criteria. The mean height z score at time of transplantation was -2.21 which by the second year post-transplantation increased significantly to -0.66 (mean increase of 1.55 standard deviation units). There were no further significant increases in mean height z score from 2 years post-transplantation until the end of follow-up at year 10. In multivariate analysis, height at transplant was the most important predictor of linear growth post-transplantation.

CONCLUSIONS

Children who underwent liver transplantation had significant catch-up growth in the first 2 years post-transplantation followed by a plateau phase. Increased height z-score at transplantation is the most important predictor of long-term growth.

Living Donor Liver Transplantation for Progressive Familial Intrahepatic Cholestasis Type 1: Two Reported Cases

BACKGROUND

Progressive familial intrahepatic cholestasis type 1 (PFIC1) is an inherited disease characterized by cholestatic features. We report two patients with PFIC1 who underwent liver retransplantation.

CASE REPORT

One patient was a 3-year-old female who underwent liver transplantation for PFIC1. She presented with severe diarrhea and fatty liver, and went into liver failure. She therefore underwent liver retransplantation and external biliary diversion 8 years after the initial liver transplantation. The explanted liver was histologically diagnosed with chronic rejection. Her intractable diarrhea stopped after the retransplantation. She was diagnosed with a fatty liver 8 months after the retransplantation and died 4 years after retransplantation due to bleeding from an ileostomy. The other patient was a 3-year-old male. This patient underwent liver retransplantation due to liver cirrhosis caused by steatohepatitis 9 years after the initial liver transplantation. The biliary tract was not diverted. He also experienced severe diarrhea after the retransplantation and requires home parenteral nutrition due to an eating disorder.

CONCLUSIONS

Liver transplantation is the only treatment to resolve life-threatening issues due to PFIC1, but requires further improvement as a therapeutic modality.

Outcomes following partial external biliary diversion in patients with progressive familial intrahepatic cholestasis

BACKGROUND/PURPOSE

PFIC is a family of bile acid (BA) transport disorders that may result in serious liver disease requiring transplantation. We reviewed our experience with PEBD as a method to improve liver function and avoid transplantation.

METHODS

All patients with PFIC were reviewed. Outcomes included changes in serum BA, conversion to ileal bypass (IB), and survival without transplantation. Statistics were obtained using paired t-test and Wilcoxon test.

RESULTS

Thirty-five patients with PFIC were identified. Data were available in 24. Twenty-four children (12 males) underwent PEBD: 10 PFIC-1, 13 PFIC-2, and one PFIC-3. BA levels decreased in PFIC-1 patients (1724±3215 to 11±6μmol/L, P=0.03) and in the single PFIC-3 patient (821 to 11.2μmol/L), but not significantly in PFIC-2 patients (193±99 to 141±118μmol/L, P=0.15). Seven patients were converted to IB. There were no significant changes in BA levels following conversion. Five-year transplant-free survival was 100% in PFIC-1 and PFIC-3, but only 38% (5/13) in PFIC-2 (P=0.004).

CONCLUSION

PEBD is an effective procedure to reduce total BA levels and improve symptoms in PFIC patients. However, it appears to be less efficacious in the PFIC-2 group. The higher BA levels could contribute to ongoing liver damage, and thus a higher transplant rate in PFIC-2 patients.

LEVEL OF EVIDENCE

Level IV.

Progressive Familial Intrahepatic Cholestasis (PFIC) in Indian Children: Clinical Spectrum and Outcome

OBJECTIVE

To study the clinical and laboratory profile of children with progressive familial intrahepatic cholestasis (PFIC) and evaluate their outcome.

METHODS

The study is a retrospective review of all cases diagnosed with PFIC between January 2011 and July 2015. All children underwent histopathological examination and immunostaining. Management was done as per institute's protocol.

RESULTS

There were a total of 24 PFIC cases (PFIC 1-2, PFIC 2-19, PFIC 3-3). Eleven presented as neonatal cholestasis, whereas 13 others presented after 6 months of life. Median age of presentation in PFIC 2 was 5.5 months with a time lag of 13 months in diagnosis. PFIC 1 and 2 presented in infancy, whereas PFIC 3 presented late. Familial clustering was seen in 12 of 24 cases. Pruritus resolved with medical management in two-thirds of cases, 3 cases required biliary diversion (BD) with dramatic improvement. One child improved after liver transplantation.

CONCLUSIONS

PFIC accounts for 8% of neonatal cholestasis and 34% of cholestasis in older children with PFIC 2 being the commonest subtype. Medical therapy is successful in majority. Partial internal BD should be offered to non-cirrhotic low gamma glutamyl transferase PFIC with intractable pruritus. Progression to cirrhosis may be prevented or delayed by early diagnosis and timely intervention.

Liver transplantation for pediatric inherited metabolic disorders: Considerations for indications, complications, and perioperative management

LT is an effective therapeutic option for a variety of IEM. This approach can significantly improve the quality of life of patients who suffer from severe disease manifestations and/or life-threatening metabolic decompensations despite medical/dietary management. Due to the significant risks for systemic complications from surgical stressors, careful perioperative management is vital. Even after LT, some disorders require long-term dietary restriction, medical management, and monitoring of metabolites. Successful liver transplant for these complex disorders can be achieved with disease- and patient-specific strategies using a multidisciplinary approach. In this article, we review indications, complications, perioperative management, and long-term follow-up recommendations for IEM that are treatable with LT.

Liver transplantation and the management of progressive familial intrahepatic cholestasis in children

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.

Bile salt export pump-reactive antibodies form a polyclonal, multi-inhibitory response in antibody-induced bile salt export pump deficiency

Progressive familial intrahepatic cholestasis type 2 (PFIC-2) is caused by mutations in ABCB11, encoding the bile salt export pump (BSEP). In 2009, we described a child with PFIC-2 who developed PFIC-like symptoms after orthotopic liver transplantation (OLT). BSEP-reactive antibodies were demonstrated to account for disease recurrence. Here, we characterize the nature of this antibody response in 7 more patients with antibody-induced BSEP deficiency (AIBD). Gene sequencing and immunostaining of native liver biopsies indicated absent or strongly reduced BSEP expression in all 7 PFIC-2 patients who suffered from phenotypic disease recurrence post-OLT. Immunofluorescence, western blotting analysis, and transepithelial transport assays demonstrated immunoglobulin (Ig) G-class BSEP-reactive antibodies in these patients. In all cases, the N-terminal half of BSEP was recognized, with reaction against its first extracellular loop (ECL1) in six sera. In five, antibodies reactive against the C-terminal half also were found. Only the sera recognizing ECL1 showed inhibition of transepithelial taurocholate transport. In a vesicle-based functional assay, transport inhibition by anti-BSEP antibodies binding from the cytosolic side was functionally proven as well. Within 2 hours of perfusion with antibodies purified from 1 patient, rat liver showed canalicular IgG staining that was absent after perfusion with control IgG.

CONCLUSIONS

PFIC-2 patients carrying severe BSEP mutations are at risk of developing BSEP antibodies post-OLT. The antibody response is polyclonal, targeting both extra- and intracellular BSEP domains. ECL1, a unique domain of BSEP, likely is a critical target involved in transport inhibition as demonstrated in several patients with AIBD manifest as cholestasis.

Autoimmune BSEP disease: disease recurrence after liver transplantation for progressive familial intrahepatic cholestasis

Severe cholestasis may result in end-stage liver disease with the need of liver transplantation (LTX). In children, about 10 % of LTX are necessary because of cholestatic liver diseases. Apart from bile duct atresia, three types of progressive familial intrahepatic cholestasis (PFIC) are common causes of severe cholestasis in children. The three subtypes of PFIC are defined by the involved genes: PFIC-1, PFIC-2, and PFIC-3 are due to mutations of P-type ATPase ATP8B1 (familial intrahepatic cholestasis 1, FIC1), the ATP binding cassette transporter ABCB11 (bile salt export pump, BSEP), or ABCB4 (multidrug resistance protein 3, MDR3), respectively. All transporters are localized in the canalicular membrane of hepatocytes and together mediate bile salt and phospholipid transport. In some patients with PFIC-2 disease, recurrence has been observed after LTX, which mimics a PFIC phenotype. It could be shown by several groups that inhibitory anti-BSEP antibodies emerge, which most likely cause disease recurrence. The prevalence of severe BSEP mutations (e.g., splice site and premature stop codon mutations) is very high in this group of patients. These mutations often result in the complete absence of BSEP, which likely accounts for an insufficient auto-tolerance against BSEP. Although many aspects of this "new" disease are not fully elucidated, the possibility of anti-BSEP antibody formation has implications for the pre- and posttransplant management of PFIC-2 patients. This review will summarize the current knowledge including diagnosis, pathomechanisms, and management of "autoimmune BSEP disease."

Progressive familial intrahepatic cholestasis

Progressive familial intrahepatic cholestasis (PFIC) is a group of rare disorders which are caused by defect in bile secretion and present with intrahepatic cholestasis, usually in infancy and childhood. These are autosomal recessive in inheritance. The estimated incidence is about 1 per 50,000 to 1 per 100,000 births, although exact prevalence is not known. These diseases affect both the genders equally and have been reported from all geographical areas. Based on clinical presentation, laboratory findings, liver histology and genetic defect, these are broadly divided into three types-PFIC type 1, PFIC type 2 and PFIC type 3. The defect is in ATP8B1 gene encoding the FIC1 protein, ABCB 11 gene encoding BSEP protein and ABCB4 gene encoding MDR3 protein in PFIC1, 2 and 3 respectively. The basic defect is impaired bile salt secretion in PFIC1/2 whereas in PFIC3, it is reduced biliary phospholipid secretion. The main clinical presentation is in the form of cholestatic jaundice and pruritus. Serum gamma glutamyl transpeptidase (GGT) is normal in patients with PFIC1/2 while it is raised in patients with PFIC3. Treatment includes nutritional support (adequate calories, supplementation of fat soluble vitamins and medium chain triglycerides) and use of medications to relieve pruritus as initial therapy followed by biliary diversion procedures in selected patients. Ultimately liver transplantation is needed in most patients as they develop progressive liver fibrosis, cirrhosis and end stage liver disease. Due to the high risk of developing liver tumors in PFIC2 patients, monitoring is recommended from infancy. Mutation targeted pharmacotherapy, gene therapy and hepatocyte transplantation are being explored as future therapeutic options.

Recovery of graft steatosis and protein-losing enteropathy after biliary diversion in a PFIC 1 liver transplanted child

PFIC 1 is a genetic disorder characterized by hepatic and gastrointestinal disease, often requiring LT during childhood. Extrahepatic symptoms, such as diarrhea and malabsorption, do not improve or may be aggravated after LT, as graft steatosis or steatohepatitis as consequences of the interaction between transplanted liver and native bowel. We describe a patient with PFIC 1 who presented with cholestasis in infancy, who developed intractable pruritus and liver fibrosis. The child underwent living donor LT at 3.6 yr of age, and he early developed severe refractory diarrhea, secondary malabsorption with protein-losing enteropathy, and an early fatty liver disease trough graft steatohepatitis. As the response to cholestyramine was unsatisfactory, we decided to perform an EBD by using the jejunal loop used for the cholangiojejunostomy. Diarrhea resolved rapidly after surgery. He remained well after six months following biliary diversion, with normal stool output and no protein loss. We documented a dramatic improvement of graft steatosis at histology as well as normalization of liver function test. EBD can be considered a valuable treatment option to avoid organ disfunction and loss in PFIC 1 transplanted patients who develop graft steatohepatitis.

Normalization of serum bile acids after partial external biliary diversion indicates an excellent long-term outcome in children with progressive familial intrahepatic cholestasis

BACKGROUND/PURPOSE

The surgical treatment for patients with progressive familial intrahepatic cholestasis (PFIC) is either liver transplantation (LTX) or partial external biliary diversion (PEBD). Both procedures achieve a good short-term outcome. However, the treatment strategy for these children remains controversial because the long-term outcome after PEBD is unknown. The aim of our study was to assess the long-term outcome and complications after PEBD in our institution.

METHODS

We retrospectively analyzed the characteristics of all patients with PFIC undergoing PEBD in our department from 1994 to 2008. The course of serum bile acids, pruritus, and liver enzymes was assessed in a regular follow-up.

RESULTS

Twenty-four patients underwent PEBD. Thirteen patients (54%) improved significantly, with a normalization of serum bile acids (P < .001 vs postoperatively) and lessened pruritus (P < .05 vs preoperatively) at 12 months after PEBD. None of these patients showed progression of cholestasis during a median follow-up of 9.8 years (range, 1.6-14.3 years). Partial external biliary diversion failed to normalize bile acids in 11 patients, of whom 9 required secondary LTX at a 1-year follow-up, with a median interval of 1.9 years (range, 0.5-3.8 years). All 7 patients (100%) with liver cirrhosis at the time of PEBD and 2 of 17 patients without cirrhosis (12%) required secondary LTX (P < .001).

CONCLUSIONS

Clinical improvement with normalization of serum bile acids within 1 year was associated with an excellent long-term outcome in patients with PEBD. The presence of liver cirrhosis at the time of PEBD indicated an unfavorable outcome. Thus, we recommend primary LTX only in PFIC patients with liver cirrhosis.

Therapeutic interventions in progressive familial intrahepatic cholestasis: experience from a tertiary care centre in north India

Medical therapy has limited value in managing symptoms of progressive familial intrahepatic cholestasis (PFIC). Liver transplantation (LT) is the only definite therapy for progressive liver failure and intractable pruritis. In recent years, biliary diversion (BD) has also shown therapeutic promise. This study was designed to review the experience of management and outcome of seven PFIC patients. Two children each had type II and III and three had type I/II PFIC, respectively. Medical treatment was successful in only one. Decompensated cirrhosis had already set in four children. They underwent a living related LT. There was one post transplant mortality. Remaining all children had a normal graft function at a mean follow-up of 50 months. One patient of PFIC type I/II received internal and another of PFIC type II received external BD. Both patients were asymptomatic at follow-up of 19 and 23 months respectively. Nontransplant surgical options should be offered to noncirrhotic children with PFIC.

Living-donor liver transplantation for progressive familial intrahepatic cholestasis

BACKGROUND

Progressive familial intrahepatic cholestasis (PFIC) results in liver cirrhosis during the disease course, although the etiology includes unknown mechanisms. Some PFIC patients require liver transplantation (LT).

METHODS

In this study, 11 patients with PFIC type 1 (PFIC1) and 3 patients with PFIC type 2 (PFIC2) who underwent living-donor LT (LDLT) were evaluated.

RESULTS

Digestive symptoms after LDLT were confirmed in 10 PFIC1 recipients (90.9%); 8 PFIC1 recipients showed steatosis after LDLT (72.7%), which began during the early postoperative period (71.5±55.1 days). Seven of the eight steatosis-positive PFIC1 recipients (87.5%) showed a steatosis degree of ≥80%, which was complicated with steatohepatitis and resulted in fibrosis. Cirrhotic findings persisted in six PFIC1 recipients even after LDLT (54.5%), and three PFIC1 recipients finally died. The survival rates of the PFIC1 recipients at 5, 10, and 15 years were 90.9%, 72.7%, and 54.5%, respectively. In contrast, the PFIC2 recipients showed good courses and outcomes without any steatosis after LDLT.

CONCLUSIONS

The clinical courses and outcomes after LDLT are still not sufficient in PFIC1 recipients owing to steatosis/steatohepatitis and subsequent fibrosis, in contrast to PFIC2 recipients. PFIC2 is good indication for LDLT. PFIC1 patients require LT during the disease course; therefore, we suggest that the therapeutic strategies for PFIC1 patients, including the timing of LDLT, under the donor limitation should be reconsidered. The establishment of more advanced treatments for PFIC1 patients is required to improve the long-term prognosis of these patients.

Living-related liver transplantation for siblings with progressive familial intrahepatic cholestasis 2, with novel genetic findings

Progressive familial intrahepatic cholestasis is a syndrome of severe cholestasis progressing to biliary cirrhosis and liver failure that develops in childhood. This report describes two siblings with PFIC-2 who underwent living-related liver transplantation from their genetically proven heterozygous parents. Both patients had normal gamma-glutamyl transpeptidase levels, but showed severe pruritus with sleep disturbance, cholestasis, jaundice and growth failure. Genetic testing of each patient revealed two missense mutations of the bile salt export pump, S901R and C1083Y, which have not previously been associated with PFIC-2. Usual medical treatment failed to improve their clinical symptoms, and the two siblings underwent living-related liver transplantation from their heterozygous parents. The transplants improved their clinical symptoms significantly, and the patients have since shown age-appropriate growth. Electron microscopic findings of the explanted liver of the younger sister revealed dense and amorphous bile, which is characteristic of PFIC-2. In the cases presented here, living-related liver transplantation from a heterozygous donor was associated with better quality of life and improvement of growth, and thus appears to be a feasible option for PFIC-2 patients. Mutation analysis is a useful tool to help decide the course of treatment of PFIC.

Recurrent low gamma-glutamyl transpeptidase cholestasis following liver transplantation for bile salt export pump (BSEP) disease (posttransplant recurrent BSEP disease)

Bile salt export pump (BSEP) deficiency is a hereditary cholestatic syndrome that results from mutations in the ABCB11 (ATP-binding cassette B11) gene. Severely affected patients develop end-stage liver disease in the first decade of life. Liver transplantation has traditionally been thought of as curative for BSEP disease. We describe the clinical course of 6 patients who developed recurrent low gamma-glutamyl transpeptidase cholestasis, that mimicks BSEP disease, following transplantation. All had documented genetic defects in ABCB11 that were predicted to lead to a congenital absence of BSEP protein. The time to development of recurrence was variable; 4 underwent repeat liver transplantation for complications of recurrent disease and all 4 again developed recurrent disease after retransplantation. Siblings of these patients who also underwent liver transplantation for BSEP disease have not developed "recurrent" disease. Three of the patients with "recurrent" disease ultimately died, 2 as a direct result of complications of their liver disease.

Favorable effect of 4-phenylacetate on liver functions attributable to enhanced bile salt export pump expression in ornithine transcarbamylase-deficient children

4-Phenylbutyrate (4-PB) acting against hyperammonemia has been administered to patients with urea cycle defects. Results of our recent experiments using animals and cultured cells strongly suggest that this agent enhances the function of bile salt export pump/ATP binding cassette B11 (BSEP/ABCB11) promoting bile acid excretion from hepatocytes to bile canaliculi, although it has not been confirmed in humans. Considering that 4-PB is converted easily into 4-phenylacetate (4-PA) in the liver, such an effect of 4-PB might occur through 4-PA. We performed retrospective analyzes of the effects of 4-PA on the liver functions of three ornithine transcarbamylase (OTC)-deficient female children receiving 4-PA. Two of the three received intravenous administration of 4-PA only at episodic periods of hyperammonemia; the remaining one received it orally at intercurrent periods. Soon after 4-PA administration, the serum total bile acid level was decreased to one-half or one-third of pre-treatment levels, but it returned to the basal levels within one month after 4-PA discontinuation. Other serum parameters for cholestasis such as gamma-glutamyl transferase also decreased markedly. Concomitantly, alanine aminotransferase and aspartate amino transferase levels decreased significantly. Western blot analyzes of the liver samples revealed that the 4-PA administration enhanced BSEP/ABCB11 protein expressions in the membranous fraction of liver cells, although the liver BSEP/ABCB11 messenger RNA level remained unchanged. These results suggest that 4-PA enhanced liver BSEP/ABCB11 function and thereby improved liver functions in OTC-deficient children. For treatment of liver disorders requiring enhancement of BSEP function, 4-PA might be a candidate.

Liver disease associated with canalicular transport defects: current and future therapies

Bile formation at the canalicular membrane is a delicate process. This is illustrated by inherited liver diseases due to mutations in ATP8B1, ABCB11, ABCB4, ABCC2 and ABCG5/8, all encoding hepatocanalicular transporters. Effective treatment of these canalicular transport defects is a clinical and scientific challenge that is still ongoing. Current evidence indicates that ursodeoxycholic acid (UDCA) can be effective in selected patients with PFIC3 (ABCB4 deficiency), while rifampicin reduces pruritus in patients with PFIC1 (ATP8B1 deficiency) and PFIC2 (ABCB11 deficiency), and might abort cholestatic episodes in BRIC (mild ATP8B1 or ABCB11 deficiency). Cholestyramine is essential in the treatment of sitosterolemia (ABCG5/8 deficiency). Most patients with PFIC1 and PFIC2 will benefit from partial biliary drainage. Nevertheless liver transplantation is needed in a substantial proportion of these patients, as it is in PFIC3 patients. New developments in the treatment of canalicular transport defects by using nuclear receptors as a target, enhancing the expression of the mutated transporter protein by employing chaperones, or by mutation specific therapy show substantial promise. This review will focus on the therapy that is currently available as well as on those developments that are likely to influence clinical practice in the near future.

[Progressive familial intrahepatic cholestasis presenting as liver failure]

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous group of autosomic-recessive inherited cholestatic disorders that begin in the neonatal period or in the first years of life. There are three types of PFIC defined by different mutations located in the gene responsible for the bile flow through the intrahepatic canalicular transporter system. These disorders usually present in children or young adults and the main clinical manifestations are cholestasis, jaundice and pruritus, and they progress slowly towards liver fibrosis in adult life. PFIC diagnosis is based on clinical suspicion, biochemical findings (that include normal gamma-glutamyl transpeptidase in type 1 and 2, but increased levels in type 3), image techniques that rule-out other disorders, and histological confirmation. Initial treatment consists of symptomatic relief of cholestatic symptoms with choleretic agents (urso-deoxycholic acid). Partial biliary derivation and ileal bypass are intermediate therapeutic options. In case of no response to these treatments, liver transplantation is indicated. We report the case of a neonate with PFIC type 2 presenting as a liver failure.

Allograft steatohepatitis in progressive familial intrahepatic cholestasis type 1 after living donor liver transplantation

We studied histological features and long-term outcomes in patients with progressive familial intrahepatic cholestasis type 1 (PFIC1) after liver transplantation (LT). Histological findings were correlated with the post-LT course and treatment in 11 recipients with PFIC1. Ages at LT varied from 1 to 18 years (median, 4 years). Macrovesicular steatosis was observed in 8 patients at a median of 60 days post-LT (range, 21-191 days). Severe steatosis progressed to steatohepatitis in 7 patients at a median of 161 days (range, 116-932 days). The patients were followed up for a median of 7.3 years (range, 2.3-16.1 years). Six showed bridging fibrosis, with 2 progressing to cirrhosis. One patient with cirrhosis died because of the rupture of a splenic artery aneurysm 13.6 years post-LT. Post-LT refractory diarrhea was present in all 8 having steatosis. Three without post-LT diarrhea showed no allograft steatosis. Bile adsorptive resin therapy reduced the diarrhea and steatosis. Patients with posttransplant steatosis typically had more severe mutations of the ATPase class I type 8B member 1 (ATP8B1) gene and were more likely to have systemic complications such as pancreatitis. In conclusion, allograft steatosis was present in patients with PFIC1, progressing to steatohepatitis and cirrhosis. Because expression of the familial intrahepatic cholestasis 1 gene occurs in several organs, including the small intestine, pancreas, and liver, and it is involved in enterohepatic bile acid circulation, post-LT steatosis may be due to a malfunction of the ATP8B1 product.

Caring for adults with pediatric liver disease

The etiology of liver disease in childhood varies significantly from its etiology in the adult population. More children with complex diseases are surviving into adulthood, providing challenges to the primary care provider. Adults with pediatric liver disease differ in management, treatment, complications, and extrahepatic considerations. To provide these patients with an optimal transition into the adult health care system, the provider needs a comprehensive knowledge of the common causes of childhood liver disease and their implications and must understand the differences in caring for these patients. This review addresses some of the most common childhood liver diseases, their causes, presentation, evaluation, management, complications, and additional concerns.

Metabolic liver disease in children

The aim of this article is to provide essential information for hepatologists, who primarily care for adults, regarding liver-based inborn errors of metabolism with particular reference to those that may be treatable with liver transplantation and to provide adequate references for more in-depth study should one of these disease states be encountered.

Metabolic liver disease in children

The aim of this article is to provide essential information for hepatologists, who primarily care for adults, regarding liver-based inborn errors of metabolism with particular reference to those that may be treatable with liver transplantation and to provide adequate references for more in-depth study should one of these disease states be encountered.