Benjamin L. Shneider

Diagnosis and management of primary sclerosing cholangitis

Preamble This guideline has been approved by the American Association for the Study of Liver Diseases and represents the position of the Association. These recommendations provide a data-supported approach. They are based on the following: (1) formal review and analysis of the recentlypublished world literature on the topic (Medline search); (2) American College of Physicians Manual for Assessing Health Practices and Designing Practice Guidelines1; (3) guideline policies, including the AASLD Policy on the Development and Use of Practice Guidelines and the American Gastroenterological Association Policy Statement on Guidelines2; and (4) the experience of the authors in the specified topic. Intended for use by physicians, these recommendations suggest preferred approaches to the diagnostic, therapeutic and preventative aspects of care. They are intended to be flexible, in contrast to standards of care, which are inflexible policies to be followed in every case. Specific recommendations are based on relevant published information. To more fully characterize the available evidence supporting the recommendations, the AASLD Practice Guidelines Committee has adopted the classification used by the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) workgroup with minor modifications (Table 1).3 The strength of recommendations in the GRADE system are classified as strong (class 1) or weak (class 2). The quality of evidence supporting strong or weak recommendations is designated by one of three levels: high (level A), moderate (level B), or low-quality (level C).

One Hundred Nine Living Donor Liver Transplants in Adults and Children: A Single-Center Experience

ObjectiveTo summarize the evolution of a living donor liver transplant program and the authors’ experience with 109 cases. Summary Background DataThe authors’ institution began to offer living donor liver transplants to children in 1993 and to adults in 1998. MethodsDonors were healthy, ages 18 to 60 years, related or unrelated, and ABO-compatible (except in one case). Donor evaluation was thorough. Liver biopsy was performed for abnormal lipid profiles or a history of significant alcohol use, a body mass index more than 28, or suspected steatosis. Imaging studies included angiography, computed tomography, endoscopic retrograde cholangiopancreatography, and magnetic resonance imaging. Recipient evaluation and management were the same as for cadaveric transplant. ResultsAfter ABO screening, 136 potential donors were evaluated for 113 recipients; 23 donors withdrew for medical or personal reasons. Four donor surgeries were aborted; 109 transplants were performed. Fifty children (18 years or younger) received 47 left lateral segments and 3 left lobes; 59 adults received 50 right lobes and 9 left lobes. The average donor hospital stay was 6 days. Two donors each required one unit of banked blood. Right lobe donors had three bile leaks from the cut surface of the liver; all resolved. Another right lobe donor had prolonged hyperbilirubinemia. Three donors had small bowel obstructions; two required operation. All donors are alive and well. The most common indications for transplant were biliary atresia in children (56%) and hepatitis C in adults (40%); 35.6% of adults had hepatocellular carcinoma. Biliary reconstructions in all children and 44 adults were with a Roux-en-Y hepaticojejunostomy; 15 adults had duct-to-duct anastomoses. The incidence of major vascular complications was 12% in children and 11.8% in adult recipients. Children had three bile leaks (6%) and six (12%) biliary strictures. Adult patients had 14 (23.7%) bile leaks and 4 (6.8%) biliary strictures. Patient and graft survival rates were 87.6% and 81%, respectively, at 1 year and 75.1% and 69.6% at 5 years. In children, patient and graft survival rates were 89.9% and 85.8%, respectively, at 1 year and 80.9% and 78% at 5 years. In adults, patient and graft survival rates were 85.6% and 77%, respectively, at 1 year. ConclusionLiving donor liver transplantation has become an important option for our patients and has dramatically changed our approach to patients with liver failure. The donor surgery is safe and can be done with minimal complications. We expect that living donor liver transplants will represent more than 50% of our transplants within 3 years.

Favorable Long-Term Outcome after Liver-Kidney Transplant for Recurrent Hemolytic Uremic Syndrome Associated with a Factor H Mutation

A male child initially presented with atypical hemolytic uremic syndrome (HUS) at the age of 4 months and progressed within weeks to end stage renal disease (ESRD). At the age of 2 years he received a live‐related kidney transplant from his mother, which, despite initial good function, was lost to recurrent disease after 2 weeks. Complement factor H analysis showed low serum levels and the presence of two mutations on different alleles (c.2918G > A, Cys973Tyr and c.3590T > C, Val1197Ala). His survival on dialysis was at risk because of access failure and recurrent bacteremic episodes. Therefore, at the age of 5 years he received a combined liver‐kidney transplant with pre‐operative plasma exchange. Initial function of both grafts was excellent and this has been maintained for over 2 years. This report suggests that despite setbacks in previous experience, combined liver‐kidney transplantation offers the prospect of a favorable long‐term outcome for patients with HUS associated with complement factor H mutations.

Intestinal Bile Acid Transport: Biology, Physiology, and Pathophysiology

Intestinal reabsorption of bile salts plays a crucial role in human health and disease. This process is primarily localized to the terminal ileum and is mediated by a 48-kd sodium-dependent bile acid cotransporter (SLC10A2 = ASBT). ASBT is also expressed in renal tubule cells, cholangiocytes, and the gallbladder. Exon skipping leads to a truncated version of ASBT, which sorts to the basolateral surface and mediates efflux of bile salts. Inherited mutation of ASBT leads to congenital diarrhea secondary to bile acid malabsorption. Partial inhibition of ASBT may be useful in the treatment of hypercholesterolemia and intrahepatic cholestasis. During normal development in the rat ileum, ASBT undergoes a biphasic pattern of expression with a prenatal onset, postnatal repression, and reinduction at the time of weaning. The bile acid responsiveness of the ASBT gene is not clear and may be dependent on both the experimental model used and the species being investigated. Future studies of the transcriptional and posttranscriptional regulation of the ASBT gene and analysis of ASBT knockout mice will provide further insight into the biology, physiology, and pathophysiology of intestinal bile acid transport.

Barriers to the successful treatment of liver disease by hepatocyte transplantation

Management of patients with hepatic failure and liver-based metabolic disorders is complex and expensive. Hepatic failure results in impaired coagulation, altered consciousness and cerebral function, a heightened risk of multiple organ system failure, and sepsis [1]. Such manifold problems are only treatable today and for the foreseeable future by transplantation. In fact, whole or auxiliary partial liver transplantation is often the only available treatment option for severe, even if transient, hepatic failure. Patients with life-threatening liver-based metabolic disorders similarly require organ transplantation even though their metabolic diseases are typically the result of a single enzyme deficiency, and the liver otherwise functions normally. For all of the benefits it may confer, liver transplantation is not an ideal therapy, even for severe hepatic failure. More than 17,000 patients currently await liver transplantation in the United States, a number that seriously underestimates the number of patients that need treatment [2], as it has been estimated that more than a million patients could benefit from transplantation [3]. Unfortunately, use of whole liver transplantation to treat these disorders is limited by a severe shortage of donors and by the risks to the recipient associated with major surgery [4].

Rapamycin Successfully Treats Post-Transplant Autoimmune Hepatitis

Rapamycin (Rapa), one of the newer immunosuppressants has been found to control and prevent autoimmune features in animal models. This is the first report describing the successful control of post‐transplant autoimmune hepatitis (AIH) with Rapa. Post‐transplant AIH is diagnosed in the presence of raised transaminases, elevated immunoglobulin G, presence of autoantibodies and histologic changes consistent with AIH on liver biopsy. It may represent a recurrence of the original AIH that led to transplantation or present as a de novo AIH after liver transplant. Post‐transplant AIH has conventionally been treated with Prednisolone (Pred) and Azathioprine (AZA). In this report, tailoring of immunosuppression after diagnosis of post‐transplant AIH is described with special emphasis on those treated successfully with Rapa. Fifteen of 21 patients responded to treatment with an increase in dose of Pred and addition of AZA or Mycophenolate Mofetil (MMF) to calcineurin inhibitor. Five non‐responders and one other patient with post‐transplant AIH were treated with addition of Rapa. All six responded to treatment but drug was withdrawn in one patient. Adverse events were minimal. Rapa may prove to be an important addition in the control of autoimmune liver disease.

Portal Hypertension in Children: Expert Pediatric Opinion on the Report of the Baveno V Consensus Workshop on Methodology of Diagnosis and Therapy in Portal Hypertension

Shneider BL, Bosch J, de Franchis R, Emre SH, Groszmann RJ, Ling SC, Lorenz JM, Squires RH, Superina RA, Thompson AE, Mazariegos GV. Portal Hypertension in Children: Expert Pediatric Opinion on the Report of the Baveno V Consensus Workshop on Methodology of Diagnosis and Therapy in Portal Hypertension.

A Retrospective Single-Center Review of Primary Sclerosing Cholangitis in Children

BACKGROUND & AIMS Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by inflammation and progressive bile duct fibrosis. There are limited data on pediatric PSC. METHODS We performed a retrospective chart review of 47 pediatric patients with PSC. RESULTS The mean age at diagnosis was 11 +/- 4.9 years. Symptoms occurred before presentation in 81% of patients; inflammatory bowel disease was found in 59% and autoimmune hepatitis (overlap syndrome) in 25% of patients. Magnetic resonance cholangiography revealed both extrahepatic and intrahepatic, isolated intrahepatic, isolated extrahepatic, and no biliary involvement (small-duct PSC) in 40%, 14%, 10%, and 36%, respectively. Advanced fibrosis (stage >II) was present in 65%. Colonoscopy revealed pancolitis, rectal sparing, and normal findings in 24%, 24%, and 18%, respectively. All patients were treated with ursodeoxycholic acid (UDCA); 9 with overlap syndrome also received immunosuppressants. Fifteen patients without overlap syndrome had positive autoimmune markers and responded to UDCA monotherapy. Liver transplantation was performed in 9 patients (3 with overlap syndrome and 2 with small-duct PSC) at a median time of 7 years after diagnosis. The 10-year posttransplant survival rate was 89%. CONCLUSIONS In one of the largest single-center studies of children with PSC, we found that most children with PSC had inflammatory bowel disease or autoimmune overlap and advanced fibrosis at diagnosis. Levels of alanine aminotransferase and gamma-glutamyl transferase were highest in patients with overlap syndrome and lowest in those with small-duct PSC. Levels of serum liver enzymes normalized after therapy with UDCA, including patients with positive autoimmune markers without histologic features of autoimmune hepatitis.

Δ4-3-Oxosteroid 5β-reductase deficiency causing neonatal liver failure and hemochromatosis☆☆☆★★★

Neonatal liver failure was evaluated in two infants. Neither infant had evidence of congenital infection, galactosemia, α1-antitrypsin deficiency, tyrosinemia, Zellweger syndrome, or hemophagocytic lymphohistiocytosis. Abnormal levels of iron were detected in the minor salivary glands of the first infant and in the explanted liver of the second. Analyses of urinary bile salts by fast-atom bombardment ionization mass spectrometry and gas chromatography-mass spectrometry revealed a paucity of primary bile acids and a predominance of 7α- hydroxy-3-oxo-4-cholenoic and 7α, 12α-dihydroxy-3-oxo-4-cholenoic acids. These findings are consistent with Δ 4-3-oxosteroid 5β-reductase deficiency, a primary genetic defect in bile acid synthesis. Postmortem evaluation of the first infant revealed significant iron deposition in the liver, pancreas, thyroid, adrenal glands, myocardium, stomach, and submucosal glands of the respiratory tract. In both infants examination of the liver revealed extensive loss of hepatic parenchyma. These cases expand the clinical spectrum of bile acid metabolism defects to include neonatal liver failure with associated hemochromatosis. (J PEDIATR 1994;124:234-8)

The membrane protein ATPase class I type 8B member 1 signals through protein kinase C zeta to activate the farnesoid X receptor

Prior loss‐of‐function analyses revealed that ATPase class I type 8B member 1 [familial intrahepatic cholestasis 1 (FIC1)] posttranslationally activated the farnesoid X receptor (FXR). Mechanisms underlying this regulation were examined by gain‐of‐function studies in UPS cells, which lack endogenous FIC1 expression. FXR function was assayed in response to wild‐type and mutated FIC1 expression constructs with a human bile salt export pump (BSEP) promoter and a variety of cellular localization techniques. FIC1 overexpression led to enhanced phosphorylation and nuclear localization of FXR that was associated with FXR‐dependent activation of the BSEP promoter. The FIC1 effect was lost after mutation of the FXR response element in the BSEP promoter. Despite similar levels of FIC1 protein expression, Byler disease FIC1 mutants did not activate BSEP, whereas benign recurrent intrahepatic cholestasis mutants partially activated BSEP. The FIC1 effect was dependent on the presence of the FXR ligand, chenodeoxycholic acid. The effect of FIC1 on FXR phosphorylation and nuclear localization and its effects on BSEP promoter activity could be blocked with protein kinase C zeta (PKC ζ) inhibitors (pseudosubstrate or small interfering RNA silencing). Recombinant PKC ζ directly phosphorylated immunoprecipitated FXR. The mutation of threonine 442 of FXR to alanine yielded a dominant negative protein, whereas the phosphomimetic conversion to glutamate resulted in FXR with enhanced activity and nuclear localization. Inhibition of PKC ζ in Caco‐2 cells resulted in activation of the human apical sodium‐dependent bile acid transporter promoter. Conclusion: These results demonstrate that FIC1 signals to FXR via PKC ζ. FIC1‐related liver disease is likely related to downstream effects of FXR on bile acid homeostasis. Benign recurrent intrahepatic cholestasis emanates from a partially functional FIC1 protein. Phosphorylation of FXR is an important mechanism for regulating its activity. (HEPATOLOGY 2008;48:1896‐1905.)