Hyperlipidemia in Chronic Cholestatic Liver Disease

Opinion statement Hyperlipidemia with a marked increase of low-density lipoprotein (LDL) and highdensity lipoprotein (HDL) cholesterol levels is a common feature in patients with chronic cholestatic liver disease. Excess morbidity and mortality from cardiovascular disease has not been reported in these patients. This may be due to the particular lipoprotein pattern observed during chronic cholestasis, characterized by elevated serum HDL cholesterol, which may have a cardioprotective effect. However, in a subgroup of patients with chronic cholestasis, hyperlipidemia is characterized by markedly elevated LDL levels with normal or low HDL levels, probably reflecting hypercholesterolemia with coexisting familial and nutritional origins. Ursodeoxycholic acid, the only drug approved for the treatment of chronic cholestatic liver diseases, has been shown to slightly decrease serum cholesterol concentrations. However, the extent of LDL reduction by ursodeoxycholic acid may be insufficient to protect this subgroup of patients from increased cardiovascular risk. Patients in this subgroup probably would benefit from dietary modification, weight loss, and the administration of specific lipid-lowering drugs. Cholestyramine, which is the first-line treatment for pruritus in chronic cholestasis, may be also indicated for its cholesterol-lowering capacity in patients with hypercholesterolemia who complain of pruritus. Administration of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors (simvastatin or pravastatin, 20 mg/d) should be limited to hypercholesterolemic patients with mild chronic cholestatic liver diseases in whom HDL serum levels are below the protective range or if additional risk factors for cardiovascular diseases are present.     

Antioxidant Enzyme Activities in Hepatic Tissue from Children with Chronic Cholestatic Liver Disease

Background/Aim:

To study the oxidative stress status in children with cholestatic chronic liver disease by determining activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) in liver tissue.

Materials and Methods:

A total of 34 children suffering from cholestatic chronic liver disease were studied. They were selected from the Hepatology Clinic, Cairo University, and compared with seven children who happened to have incidental normal liver biopsy. The patients were divided into three groups: extrahepatic biliary atresia (n=13), neonatal hepatitis (n=15) and paucity of intrahepatic bile ducts (n=6); GPx, SOD and CAT levels were measured in fresh liver tissue using ELISA.

Results:

In the cholestatic patients, a significant increase was found in mean levels of SOD, GPx and CAT in hepatic tissue compared to control children. The three enzymes significantly increased in the extrahepatic biliary atresia group, whereas in the groups of neonatal hepatitis and paucity of intrahepatic bile ducts, only GPx and CAT enzymes were significantly increased.

Conclusion:

Oxidative stress could play a role in the pathogenesis of cholestatic chronic liver diseases. These preliminary results are encouraging to conduct more extensive clinical studies using adjuvant antioxidant therapy.     

End-stage Liver Disease in Children

Opinion statement The treatment of children with end-stage liver disease involves the coordinated management of nutritional deficiencies, ascites, pruritus, encephalopathy, and portal hypertension. The implementation of management strategies depends upon a parent or guardian to administer the plan in the context of a child at different stages of developmental, physiologic, emotional, and physical maturity. Fat-soluble vitamins (A, D, E, and K) and micronutrient levels should be monitored routinely and supplemented if deficient. In some patients, supplemental nutrition to provide additional energy and protein is needed to ensure optimal growth and development. Ascites often respond to spironolactone and sodium restriction, but may require the addition of a loop diuretic or even abdominal paracentesis. Pruritus significantly impairs the quality of life of patients and is typically treated with ursodeoxycholic acid, rifampin, or an antihistamine. Partial biliary diversion, or liver transplant in some instances, is necessary for patients with self-mutilating pruritus that results from intrahepatic cholestasis. Hepatic encephalopathy is poorly defined in infants and small children. Elevated serum ammonia serves as a surrogate marker for encephalopathy, which is treated with dietary protein restriction and lactulose. The usefulness of medical prophylaxis for esophageal varices has been noted in adults, though such studies have not been performed in children. If variceal bleeding becomes problematic, treatment with endoscopic variceal banding or sclerotherapy is indicated. A surgical shunt to reduce portal pressure is needed in some cases. Orthotopic liver transplant ultimately may be necessary to overcome the unrelenting consequences of end-stage liver disease.     

Cholestatic Liver Disease in a 20-Yr-Old Woman with Histiocytosis X

A 20-yr-old woman with known diabetes insipidus complained of high fever and jaundice. Liver specimens biopsied under peritoneoscopy showed proliferating histiocytic or foamy cells in periportal areas. Immunocytochemical investigation demonstrated the presence of S-100 protein, but the absence of lysozyme in their histiocytic cells, and ultrastructural study revealed Birbeck granules in them. Vinblastine therapy reduced jaundice and high fever, and diabetes insipidus was controlled. Clinical, immunohistological, and cytological features suggested Letter-Siwe disease with jaundice, which responded well to treatment.     

Ursodeoxycholic Acid Suppresses Extent of Lipid Peroxidation in Diseased Liver in Experimental Cholestatic Liver Disease

The therapeutic benefit of ursodeoxycholic acid (UDCA) in treating cholestatic liver disease is globally recognized. It is generally accepted that the mechanism of action of UDCA can be attributed to several diverse processes that appear to be uniformly targeted towards minimizing the deleterious actions of accumulated hydrophobic bile acids in the cholestatic liver. Since hydrophobic bile acids are prooxidants, emerging in vitro evidence suggests that UDCA may have an antioxidant mechanism of action. We hypothesize that UDCA suppresses the extent of lipid peroxidation in the cholestatic liver. This hypothesis was tested by assessing the extent of lipid peroxidation in livers harvested from chronic bile duct ligated (CBDL) rats dosed daily for 24 days with 5, 10, or 15 mg/kg UDCA. The extent of lipid peroxidation was evaluated by determining the hepatic content of conjugated dienes, lipid peroxides, and malondialdehyde. The data were compared with identical data collected from unoperated control and 24-day bile duct manipulated (SO) rats. In the two groups of control rats, UDCA has no effect on the serum indices of liver function. In CBDL rats, UDCA suppressed the increased extent of lipid peroxidation in the liver in a dose-dependent manner in the absence of improvement of laboratory parameters of liver function and hepatic architecture. In conclusion, UDCA suppresses the augmented extent of lipid peroxidation in the diseased liver of CBDL rats.     

Therapeutics for Pruritus in Cholestatic Liver Disease: Many Treatments but Few Cures

Purpose of Review

Pruritus in cholestatic liver disease is commonly encountered and difficult to eradicate. It has a major impact on quality of life and thus is important to address. This article reviews current and future treatment options for cholestatic pruritus.

Recent Findings

In the last 5 years, the pathogenesis of cholestatic itch has been further clarified via studies of serum autotaxin, which correlates with severity of symptoms and decrease in patients on therapy. New medications under development include apical sodium-dependent bile acid transporters (maralixibat, GSK2330672), fibrates (bezafibrate), and κ-opioid receptor agonists (nalfurafine hydrochloride).

Summary

While many treatments are available to treat this vexing condition, data to support consistent and dramatic improvement with any one medication is lacking. However, with so many options and several new medications under investigation in clinical trials, symptom relief is an achievable goal for many patients.

     

Secondary Osteoporosis in Liver Transplant Recipients: a Longitudinal Study in Patients With and Without Cholestatic Liver Disease

Background: Metabolic bone disease is one of the major long-term complications in liver transplant recipients, but it remains unclear which patients are at highest risk for developing severe bone disease following transplantation. Methods: A total of 46 consecutive, adult patients with chronic liver disease accepted for a liver transplantation waiting list were prospectively included in the study. The patients were classified into two groups: group A—chronic cholestatic liver disease (n = 28), and group B—chronic non-cholestatic liver disease (n = 18). Bone mineral density (BMD) was measured at acceptance for the waiting list and at 3, 12 and 36 months following transplantation. Markers of bone turnover (serum-bone specific alkaline phosphatases (bALP), s-osteocalcin, s-l-collagen-C-terminal telopeptide (1-CTP) and urine N-terminal telopeptides u-Ntx) were measured at acceptance and at 3, 6, 12, 24 and 36 months following transplantation. BMD and markers of bone turnover were compared with similar values in a matched control group of 42 healthy individuals. Results: BMD decreased significantly during the early post-transplantation period (median bone loss femoral neck (FN) 3 months post-transplant 8.5%). BMD levels declined slightly from 3 to 12 months following transplantation and increased thereafter. The relative bone loss was greatest among group B patients (relative bone loss FN 3 months post-transplant: group A, 8% versus group B, 13%; P = 0.04). At 36 months, 8/17 group A and 2/9 group B patients had BMD levels that exceeded the pretransplant levels (P = 0.12). The early bone loss was positively correlated with an increase in resorption markers (s-1-CTP and u-Ntx). Group B had higher levels of both s-1-CTP and u-Ntx at 3 and 6 months post-transplant than group A patients (P = 0.03). Bone formation markers increased slowly from 6 months post-transplant and onwards. Relative bone loss was positively correlated to total glucocorticoid dose during the first 3 months post-transplant. There were no differences in BMD between patients receiving tacrolimus versus those receiving'cyclosporin A. Conclusion: Bone loss following liver transplantation is considerable in patients with both cholestatic and non-cholestatic liver disease, the first group has the poorest starting-point while the latter group has the greatest bone loss following transplantation. Bone loss is closely correlated with biochemical markers of bone resorption and total dose of glucocorticoids given post-transplant.