The management of autoimmunity in patients with cholestatic liver diseases

Cholestatic liver diseases are rare diseases that often lead to cirrhosis and its consequent complications. In addition to liver-related morbidity, patients with cholestatic liver diseases often suffer from autoimmune diseases that affect several organs and tissues. The robust and efficient data collection and collaboration between hepatologists and rheumatologists have led to significant advancements in understanding the relationship between the cholestatic liver diseases and associated autoimmune diseases. In this paper, we discuss the cholestatic liver diseases (primary biliary cirrhosis, primary sclerosing cholangitis and immunoglobulin G4 associated cholangitis) and associated autoimmune diseases.     

胆汁淤积性肝病的病因

正胆汁主要由肝细胞和胆管细胞分泌产生,其形成机制十分复杂。胆汁淤积是由于肝细胞或胆管细胞水平上的胆汁生成障碍、分泌障碍和(或)流动障碍所导致的胆汁流无法正常流入十二指肠,而反流入血液循环中的一种病理状态~[1]。临床上可有黄疸、瘙痒、乏力、尿色加深等症状。患者早期通常不出现以上症状,仅表现为血清碱性磷酸酶(alkalinephos phatase,ALP)和γ-谷氨酰转肽酶(gammaglutamy     

Pharmacotherapy of cholestatic liver diseases

New insights into the molecular mechanisms of bile formation and cholestasis have provided new concepts for pharmacotherapy of cholestatic liver diseases. The major aim in all forms of cholestasis is the reduction of hepatocellular retention of bile acids and other potentially toxic constituents of bile. Reduction of hepatocellular retention may be achieved by drugs that stimulate hepatocellular secretion via the canalicular route into the bile or via the alternative route across the basolateral membrane into the blood, and by drugs that stimulate the hepatocellular metabolism of hydrophobic bile acids to hydrophilic, less toxic metabolites. In cholestatic liver diseases that start with an injury of the biliary epithelium (e.g., primary biliary cirrhosis; PBC), protection of the cholangiocytes against the toxic effects of hydrophobic bile acids is most important. When hepatocellular retention of bile acids has occurred, the inhibition of bile acid-induced apoptosis becomes another target of therapy. Ursodeoxycholic acid protects the biliary epithelium by reducing the toxicity of bile, stimulates hepatobiliary secretion by upregulating transporters and inhibits apoptosis. It is the mainstay of therapy in PBC but of benefit also in a number of other cholestatic liver diseases. New drugs such as 6-ethyl-chenodeoxycholic acid and 24-nor-ursodeoxycholic acid are being evaluated for the treatment of cholestatic liver diseases.     

胆汁淤积性肝病的规范化诊断

正胆汁淤积是指胆汁形成、分泌或排泄障碍,不能正常流入十二指肠而逆流入血的病理状态。肝内外各种原因导致的以胆汁淤积为主要表现的肝胆系统疾病统称为胆汁淤积性肝病。胆汁淤积性肝病病因复杂,诊断困难。一般来说,胆汁淤积性肝病预后较好,但当病情较重、病程较长、发生在易感人群     

The relative expression of hepatocellular and cholestatic liver enzymes in adult patients with liver disease

Introduction and objectivesHepatocellular liver injury is characterized by elevations in serum alanine (ALT) and aspartate (AST) aminotransferases while cholestasis is associated with elevated serum alkaline phosphatase (ALP) levels. When both sets of enzymes are elevated, distinguishing between the two patterns of liver disease can be difficult. The aim of this study was to document the predicted ranges of serum ALP values in patients with hepatocellular liver injury and ALT or AST values in patients with cholestasis.Materials and methodsLiver enzyme levels were documented in adult patients with various types and degrees of hepatocellular (non-alcoholic fatty liver disease, hepatitis B and C, alcohol and autoimmune hepatitis) and cholestatic (primary biliary cholangitis and primary sclerosing cholangitis) disease.ResultsIn 5167 hepatocellular disease patients with ALT (or AST) values that were normal, 1–5×, 5–10× or >10× elevated, median (95% CI) serum ALP levels were 0.64 (0.62–0.66), 0.72 (0.71–0.73), 0.80 (0.77–0.82) and 1.15 (1.0–1.22) fold elevated respectively. In 252 cholestatic patients with ALP values that were normal, 1–5× or >5× elevated, serum ALT (or AST) values were 1.13 (0.93–1.63), 2.47 (2.13–2.70) and 4.57 (3.27–5.63) fold elevated respectively. In 56 patients with concurrent diseases, ALP levels were beyond predicted values for their hepatitis in 38 (68%) and ALT (or AST) values beyond predicted values for their cholestatic disorder in 24 (43%).ConclusionsThese data provide health care providers with predicted ranges of liver enzymes in patients with hepatocellular or cholestatic liver disease and may thereby help to identify patients with concurrent forms of liver disease.     

Serum dolichols in chronic cholestatic liver diseases

BACKGROUND/AIMS: Dolichols are long-chain polyisoprenoid alcohols. It has been suggested that they modify membrane fluidity, stability and permeability. Some lysosomal diseases are associated with elevated serum dolichol levels. Liver has been suggested to play an important role in the regulation of serum dolichol levels and biliary excretion of dolichols has been proposed to be the main elimination route for dolichols from the body. The possible effect of liver diseases on serum dolichol, however, is not known. METHODS: We therefore studied the effect of early or intermediate primary biliary cirrhosis, primary sclerosing cholangitis and alcoholic liver cirrhosis on serum dolichol concentration. Furthermore, serum dolichol content was measured in patients with end-stage primary biliary cirrhosis, primary sclerosing cholangitis and chronic active hepatitis, waiting to be transplanted. RESULTS: As compared to age-adjusted controls, serum dolichol was significantly increased in early and intermediate primary biliary cirrhosis (451+/-56 ng/ml vs. 225+/-13 ng/ml, p<0.0001) and primary sclerosing cholangitis (315+/-16 ng/ml vs. 224+/-7 ng/ml, p<0.0001). However, in alcoholic liver cirrhosis serum dolichol was unaffected. Serum dolichol content was also significantly elevated in patients with end-stage primary biliary cirrhosis (844+/-210 ng/ml vs. 225+/-13, p<0.001) and chronic active hepatitis (594+/-198 vs. 224+/-7 ng/ml, p<0.02). Furthermore, in patients with liver diseases serum dolichol concentration correlated positively with serum high density lipoprotein (HDL)-cholesterol (r = +0.50, p<0.0001). CONCLUSIONS: Serum dolichol levels are elevated in all stages of chronic cholestatic liver diseases but not in alcoholic liver cirrhosis. Impaired biliary excretion of dolichols appears to be the primary explanation for this finding.     

Bile acid abnormalities in cholestatic liver diseases

There is ample reason to believe that UDCA is the drug of choice in cholestatic liver diseases. It is possible that UDCA has to be administered for prolonged periods to see appreciable reversal in liver damage. Nevertheless, the amelioration of symptoms and improvement in nutrition of patients are equally important. Disabling symptoms such as pruritus are often brought under control, and quality of life improves. Clearly the goal for UDCA therapy is to slow the rate of disease progression, lessen the mortality risk, and improve the quality of life in patients. It is possible that a combination therapy would be more beneficial than UDCA alone. Initial results of administering UDCA with colchicine have shown no improvement in liver histology; however, administration of UDCA together with a strong anti-inflammatory drugs may be helpful to halt immune destruction of liver cells.     

Overlap syndromes with autoimmune hepatitis in chronic cholestatic liver diseases

Conditions exhibiting features of two different autoimmune liver diseases are commonly designated overlap syndromes, although there is no current agreement on what constitutes an overlap syndrome or specific diagnostic criteria. As in the classic autoimmune liver diseases, such as autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), the etiology is unknown but presumed to be related to alterations of immune regulation. Distinction of these clinical entities is important for management as outcomes may differ from outcomes of patients with diagnosis of classic autoimmune liver diseases. Due to their presumed rarity, no large therapeutic trials are available and treatment of overlap conditions is empirical and based upon extrapolation of data from the primary autoimmune liver diseases. PBC–AIH overlap is the most frequently described overlap syndrome and may be associated with a poor prognosis. This may represent an important and unrecognized cause of resistance to ursodeoxycholic acid in patients with PBC. PSC–AIH overlap is less commonly reported. Prognosis may be better than in patients with PSC alone; however, worse than in patients with AIH alone. Further studies are needed for determining diagnosis, natural history and optimal therapeutic strategies of overlap syndromes of autoimmune liver disease.     

Review: Pathogenesis of cholestatic liver diseases

Cholestatic liver diseases (CLD) begin to develop after an impairment of bile flow start to affect the biliary tree. Cholangiocytes actively participate in the liver response to injury and repair and the intensity of this reaction is a determinant factor for the development of CLD. Progressive cholangiopathies may ultimately lead to end-stage liver disease requiring at the end orthotopic liver transplantation. This narrative review will discuss cholangiocyte biology and pathogenesis mechanisms involved in four intrahepatic CLD: Primary biliary cholangitis, primary sclerosing cholangitis, cystic fibrosis involving the liver, and polycystic liver disease.     

重视胆汁淤积性肝病的诊断和药物治疗

正胆汁淤积(cholestasis)的定义为由于遗传缺陷、机械性障碍、免疫系统调节异常、毒素作用等因素损伤胆管,导致胆汁形成和分布障碍,造成肠道胆汁缺乏,而过多潜在毒性的胆汁成分在肝细胞、胆管和体循环中的蓄积。临床可表现为黄疸、高胆固醇血症、皮肤瘙痒,同时伴有血清酶学的异常,最终可发展为肝纤维化、肝硬化甚至肝衰竭。2015年中华医学会肝病学分会、中华医学会消化病学分会、中华医学会感染病学分会联合发布了《胆汁淤积性     

Bone density and metabolism in patients with viral hepatitis and cholestatic liver diseases before and after liver transplantation

OBJECTIVE: Osteoporosis is frequently found in patients with cholestatic liver disease (primary biliary cirrhosis/primary sclerosing cholangitis) and chronic viral hepatitis. There is limited information about the long-term effect of liver transplantation (OLT) on bone metabolism. The aim of this study was to investigate the effect of liver transplantation on bone metabolism in patients with cholestatic and viral liver diseases. METHODS: We randomly recruited 193 patients with chronic viral hepatitis or cholestatic liver diseases. Bone density (Z-score) and markers of bone metabolism (intact parathyroid hormone [iPTH], PTH 70-84, osteocalcin, procollagen, telopeptide, and vitamin D) were determined before and at time points (< and > 24 months) post-OLT. RESULTS: Before OLT, bone density (Z-score) was decreased in patients with cholestatic (-1) and viral (-0.4) liver diseases. In both groups bone density continued to decrease in the periods up to and more than 24 months after OLT. In the cholestatic group, bone density decreased significantly compared to pre-OLT (p < 0.05) and to the viral hepatitis group (p < 0,001). Markers of bone metabolism showed that after OLT, bone metabolism was enhanced and shifted versus bone resorption. Immunosuppressive drug therapy (glucocorticoids, cyclosporin, FK 506) directly correlated with increased bone metabolism post-OLT. CONCLUSIONS: Bone loss is a long-term problem after OLT, particularly in patients with cholestatic liver diseases. Drug therapy is a main factor of bone loss. Pre- and post-OLT therapy to reduce bone loss is recommended.     

Hepatic clearance of unconjugated bilirubin in cholestatic liver diseases

The hepatic clearance of unconjugated bilirubin-¹⁴C from the plasma of 5 patients with cholestatic liver disease was normal when compared with values obtained in healthy young adults. In 1 patient with benign recurrent cholestasis, clearance was the same during an attack of cholestasis (serum bilirubin concentration 25.7 mg/100 ml) as when the patient was in remission (serum bilirubin concentration 0.65 mg/100 ml). We conclude that the hepatic clearance of unconjugated bilirubin may not be altered in hepatic disorders where cholestasis is the predominant feature and that other explanations should be considered when patients with these disorders manifest an increased plasma concentration of unconjugated bilirubin.the Metabolism Branch, National Cancer Institute, National Institutes of Health.