Autoimmune liver disease - are there spectra that we do not know?

Autoimmune liver diseases (AILDs) are common leading causes for liver cirrhosis and terminal stage of liver disease. They have variable prevalence among patients with liver disease and have two major clinical and biochemical presentations. Autoimmune hepatitis (AIH) is the typical example of hepatocellular AILD, but it can also be presented under a cholestatic pattern. AIH has a scoring diagnostic system and respond in most cases to the treatment with prednisolone and azathioprine. Primary biliary cirrhosis (PBC) is the second most common AILD, with a cholestatic presentation and characterized by positive antimitochondrial antibody (AMA). It has an excellent response and long term outcome with the administration of ursodeoxycholic acid (UDCA). Another AILD that is thought to be a variant of PBC is the autoimmune cholangitis, being a disease that has biochemical and histological features similar to PBC; but the AMA is negative. Primary sclerosing cholangitis (PSC) is a rare entity of AILD that has a cholestatic presentation and respond poorly to the treatment, with the ultimate progression to advance liver cirrhosis in most patients. Other forms of AILD include the overlap syndromes (OS), which are diseases with mixed immunological and histological patterns of two AILD; the most commonly recognized one is AIH-PBC overlap (AIH-PSC overlap is less common). The treatment of OS involves the trial of UDCA and different immunosuppressants. Here we present three case reports of unusual forms of chronic liver diseases that most likely represent AILD. The first two patients had a cholestatic picture, whereas the third one had a hepatocellular picture at presentation. We discussed their biochemical, immunological and histological features as well as their response to treatment and their outcomes. Then, we compared them with other forms of AILD.     

Leptin in the treatment of lipodystrophy-associated nonalcoholic fatty liver disease: are we there already?

Evaluation of: In general, nonalcoholic fatty liver disease (NAFLD) consists of ectopic fat accumulation in the liver, when the ability to store fat in inert reservoirs is overcome. That occurs either when we have an excess of energy/fat such as in obesity, or when adipose tissue is defective, not being able to store even regular amounts of energy, such as in lipodystrophies (LDs). LD associates with metabolic deregulation: insulin resistance/diabetes mellitus and dyslipidemia. Several small studies have shown a beneficial effect of leptin replacement, an adipocyte-derived hormone, in the metabolic profile of patients with LD. The paper under evaluation studied 50 patients with LD-associated NAFLD treated with leptin, suggesting a beneficial effect in liver histology and in decreasing not only steatosis, but also nonalcoholic steatohepatitis, although with no effect on fibrosis after 2 years of treatment.     

Are there useful biochemical markers of disease activity in lysosomal storage diseases?

The primary biochemical consequence of a defect in a gene encoding a functional component of the lysosomal system is disruption of the catabolism or processing of macromolecules in the lumen of the lysosome. Transport of the resulting digestion products through the lysosomal membrane may also be affected. This leads to the accumulation of specific metabolites within the lysosomes of affected cells. The nature of these storage products depends upon the functional protein affected and the cell type. The accumulation of storage products is progressive and leads to hypertrophy of the lysosomal system, the hallmark of lysosomal storage diseases (LSDs).Subsequent cell necrosis or, possibly, exocytosis results in the appearance in body fluids of the storage products and components of the lysosomes at much higher concentrations than seen in normal unaffected individuals. Measurement of these increased levels of metabolites and proteins provides disease-specific and generic biochemical markers for LSDs. Secondary changes in metabolism and cellular function may also produce characteristic changes in the levels of metabolites or proteins, which can also be used as markers of the disease process. Although the rate of appearance of these biochemical markers in an individual will depend upon the underlying mutation in the gene and on other genetic and environmental factors, it provides a good indicator of the progression of the disease. As the novel forms of treatment being developed may reverse the hypertrophy of the lysosomal system, biochemical markers could also be used to monitor the reversal of pathology and the efficacy of treatment.     

Noninvasive markers of fibrosis for longitudinal assessment of fibrosis in chronic liver disease: are they ready for prime time?

Over the past decade, there has been a renewed enthusiasm to develop noninvasive serum markers or tests to assess the presence and severity of fibrosis in chronic liver disease. Although a single marker or test has lacked the necessary accuracy to predict fibrosis, different combinations of these markers or tests have shown encouraging results. However, inter-laboratory variability and inconsistent results with liver diseases of varying etiologies have made it difficult to assess the reliability of these markers in clinical practice. In this issue of the journal, Poynard et al. describe the "histological" response to lamivudine in patients with chronic Hepatitis B Virus (HBV) over a 24-month period using surrogate serum biomarkers (Fibrotest-Actitest, FT-AT) without corroborating histological data. Investigators found improvement in fibrosis and inflammation in 85% and 91%, respectively, despite the emergence of YMDD mutation in 41.5% of patients. The higher improvement rates reported in this study should be interpreted with caution for a number of reasons including the absence of data on virological response rates, corroboratory histological data, and data on the validity of FT to evaluate fibrosis in a longitudinal manner. Although FT has been studied extensively by the authors of the current study, to date there are only few independent studies. In addition to significant inter-laboratory variations, these studies have shown that significant fibrosis could be missed, or conversely significant fibrosis diagnosed in the absence of minimal or no fibrosis in about 15% to 20% of patients. We may be approaching a time when serum biomarkers may become an integral part of the assessment of patients with chronic liver disease, but published evidence suggests that these markers are not yet ready for prime time.     

Noninvasive markers of fibrosis for longitudinal assessment of fibrosis in chronic liver disease: are they ready for prime time?

Over the past decade, there has been a renewed enthusiasm to develop noninvasive serum markers or tests to assess the presence and severity of fibrosis in chronic liver disease. Although a single marker or test has lacked the necessary accuracy to predict fibrosis, different combinations of these markers or tests have shown encouraging results. However, interlaboratory variability and inconsistent results with liver diseases of varying etiologies have made it difficult to assess the reliability of these markers in clinical practice. In this issue of the Journal, Poynard and colleagues describe the "histological" response to lamivudine in patients with chronic HBV over a 24-month period using surrogate serum biomarkers (FibroTest-ActiTest) without corroborating histological data. Investigators found improvement in fibrosis and inflammation in 85% and 91%, respectively, despite the emergence of YMDD mutation in 41.5% of patients. The higher improvement rates reported in this study should be interpreted with caution for a number of reasons including the absence of data on virological response rates, corroboratory histological data, and data on the validity of FibroTest to evaluate fibrosis in a longitudinal manner. Although FibroTest has been studied extensively by the authors of the current study, to date there are only few independent studies. In addition to significant interlaboratory variations, these studies have shown that significant fibrosis could be missed, or conversely significant fibrosis diagnosed in the absence of minimal or no fibrosis in about 15-20% of patients. We may be approaching a time when serum biomarkers may become an integral part of the assessment of patients with chronic liver disease, but published evidence suggests that these markers are not yet ready for prime time.     

Is there any progress in the treatment of non-alcoholic fatty liver disease?

Despite the fact that non-alcoholic fatty liver disease(NAFLD) and its severe clinical form,non-alcoholic steatohepatitis,are becoming increasingly prevalent in the industrialised countries,there are no licensed pharmacological treatments for them.Weight loss and life modifications,antioxidant therapies and insulin-sensitising agents are the current treatment strategies and have all been tested with inconclusive results.Low sample numbers,inadequate treatment duration and invalid surrogate markers for treatment response might all account for these results.As NAFLD is a systemic rather than a liver disease,future trials should address the patient as a whole and also address cardiovascular risk factors.     

Endorectal advancement flap: are there predictors of failure?

PURPOSE: The management of complex perianal fistulas with endorectal advancement flap is aimed at avoiding the risk of sphincter injury associated with traditional surgical methods. Long-term follow-up is required to assess the recurrence and continence outcomes of this procedure. The aim of this study was to review our experience with endorectal advancement flap in the treatment of complex perianal fistulas and to define the predictors of successful healing. METHODS: A retrospective chart review of all patients who underwent endorectal advancement flap for complex perianal fistulas between 1988 and 2000 was performed. Follow-up was established by telephone interview. RESULTS: One hundred six consecutive endorectal advancement flap procedures were performed on 94 patients (94.4 percent). There were 56 females (59.6 percent). Mean age was 41.6 (range, 18–76) years. Cryptoglandular disease was the most common cause of fistula (n = 41, 43.6 percent), followed by Crohns disease (n = 28, 29.8 percent). At a mean follow-up of 40.3 (range, 1–149) months, the procedure was successful in 56 (59.6 percent) of 94 patients. Twelve patients underwent repeat surgery with the same technique because of initial failure, 8 of whom eventually healed. Crohns disease was associated with a significantly higher recurrence rate (57.1 percent) when compared with fistulas in patients without Crohns disease (33.3 percent, P < 0.04). Prior attempts at repair of the fistula were not associated with less favorable outcome of the procedure (P = 0.5). Recurrence was not associated with the type of fistula, origin, preoperative steroid use, postoperative bowel confinement, use of postoperative antibiotics, or creation of a diverting stoma. The median time to recurrence was 8 (range, 1–156) weeks; there was no postoperative mortality. Two patients had postoperative bleeding, one requiring resuture of the flap on the first postoperative day. Recurrences were observed in 15.7 percent of the patients 3 or more years after the repair. In 8 patients (9 percent), continence deteriorated after the endorectal advancement flap, a more common finding in patients who had undergone previous surgical repairs (P < 0.02). CONCLUSION: The success rate of endorectal advancement flap for complex perianal fistulas is modest. Failure is mainly correlated with the presence of Crohns disease.     

Is coeliac disease a potentially treatable cause of liver failure?

Hypertransaminasaemia is a common abnormality found in up to 40% of untreated coeliac patients, which resolves with the institution of a gluten-free diet. A much rarer occurrence is the association of chronic liver disease with coeliac disease. Primary biliary cirrhosis, primary sclerosing cholangitis, and chronic autoimmune hepatitis have all been recognized in coeliac patients. More recently, the occurrence of coeliac disease in patients with chronic liver disease is found to be 10 times greater than that in the general population. Of particular note are the 13 patients reported to date with liver failure and coeliac disease. Among those patients commenced on a gluten-free diet an improvement in liver function was observed. The relationship between coeliac disease, a gluten-free diet, and the course of chronic liver disease needs to be clarified.     

Is there a role of lipid-lowering therapies in the management of fatty liver disease?

Atherogenic dyslipidemia is characterized by increased triglyceride-rich lipoproteins and low high-density lipoprotein cholesterol concentrations. It is highly prevalent in non-alcoholic fatty liver disease (NAFLD) and contributes to the increased cardiovascular risk associated with this condition. Alongside insulin resistance it plays an important pathogenetic role in NAFLD/non-alcoholic steatohepatitis (NASH) development and progression. It has been shown that cholesterol-lowering reduces cardiovascular risk more in NAFLD vs non-NAFLD high-risk individuals. This evidence highlights the importance of effective lipid modulation in NAFLD. In this narrative review the effects of the most commonly used lipid-lowering therapies on liver outcomes alongside their therapeutic implications in NAFLD/NASH are critically discussed. Preclinical and clinical evidence suggests that statins reduce hepatic steatosis, inflammation and fibrosis in patients with NAFLD/NASH. Most data are derived from observational and small prospective clinical studies using changes in liver enzyme activities, steatosis/fibrosis scores, and imaging evidence of steatosis as surrogates. Also, relevant histologic benefits were noted in small biopsy studies. Atorvastatin and rosuvastatin showed greater benefits, whereas data for other statins are scarce and sometimes conflicting. Similar studies to those of statins showed efficacy of ezetimibe against hepatic steatosis. However, no significant anti-inflammatory and anti-fibrotic actions of ezetimibe have been shown. Preclinical studies showed that fibrates through peroxisome proliferator-activated receptor (PPAR)α activation may have a role in NAFLD prevention and management. Nevertheless, no relevant benefits have been noted in human studies. Species-related differences in PPARα expression and its activation responsiveness may help explain this discrepancy. Omega-3 fatty acids reduced hepatic steatosis in numerous heterogeneous studies, but their benefits on hepatic inflammation and fibrosis have not been established. Promising preliminary data for the highly purified eicosapentaenoic acid require further confirmation. Observational studies suggest that proprotein convertase subtilisin/kexin9 inhibitors may also have a role in the management of NAFLD, though this needs to be established by future prospective studies.