Treatment options for primary sclerosing cholangitis

Trust Your Gut: The Association of Gut Microbiota and Liver Disease

The gut microbiota composition is important for nutrient metabolism, mucosal barrier function, immunomodulation, and defense against pathogens. Alterations in the gut microbiome can disturb the gut ecosystem. These changes may lead to the loss of beneficial bacteria or an increase in potentially pathogenic bacteria. Furthermore, these have been shown to contribute to the pathophysiology of gastrointestinal and extra-intestinal diseases. Pathologies of the liver, such as non-alcoholic liver disease, alcoholic liver disease, cirrhosis, hepatocellular carcinoma, autoimmune hepatitis, viral hepatitis, and primary sclerosing cholangitis have all been linked to changes in the gut microbiome composition. There is substantial evidence that links gut dysbiosis to the progression and complications of these pathologies. This review article aimed to describe the changes seen in the gut microbiome in liver diseases and the association between gut dysbiosis and liver disease, and finally, explore treatment options that may improve gut dysbiosis in patients with liver disease.

A Review of Extraintestinal Manifestations and Complications of Inflammatory Bowel Disease

Extraintestinal manifestations (EIMs) are common in inflammatory bowel disease (IBD), in both Crohn's disease and ulcerative colitis. Almost any organ system can be affected, including the musculoskeletal, dermatologic, renal, hepatopancreatobiliary, pulmonary and ocular systems. However, the musculoskeletal and dermatologic systems are the most commonly involved sites of manifestations. While some manifestations such as peripheral arthritis and erythema nodosum have an association with IBD activity, others such as axial arthropathy, pyoderma gangrenosum and primary sclerosing cholangitis have an independent disease course. This review provides a summary of the most common EIMs in IBD and their prevalence and management.

Cholangitis: Diagnosis, Treatment and Prognosis

Cholangitis is a serious life-threatening situation affecting the hepatobiliary system. This review provides an update regarding the clinical and pathological features of various forms of cholangitis. A comprehensive search was performed in the PubMed, Scopus, and Web of Knowledge databases. It was found that the etiology and pathogenesis of cholangitis are heterogeneous. Cholangitis can be categorized as primary sclerosing (PSC), secondary (acute) cholangitis, and a recently characterized form, known as IgG4-associated cholangitis (IAC). Roles of genetic and acquired factors have been noted in development of various forms of cholangitis. PSC commonly follows a chronic and progressive course that may terminate in hepatobiliary neoplasms. In particular, PSC commonly has been associated with inflammatory bowel disease. Bacterial infections are known as the most common cause for AC. On the other hand, IAC has been commonly encountered along with pancreatitis. Imaging evaluation of the hepatobiliary system has emerged as a crucial tool in the management of cholangitis. Endoscopic retrograde cholangiography, magnetic resonance cholangiopancreatography and endoscopic ultrasonography comprise three of the modalities that are frequently exploited as both diagnostic and therapeutic tools. Biliary drainage procedures using these methods is necessary for controlling the progression of cholangitis. Promising results have been reported for the role of antibiotic treatment in management of AC and PSC; however, immunosuppressive drugs have also rendered clinical responses in IAC. With respect to the high rate of complications, surgical interventions in patients with cholangitis are generally restricted to those patients in whom other therapeutic approaches have failed.

Characterization of Intestinal Microbiota in Ulcerative Colitis Patients with and without Primary Sclerosing Cholangitis

BACKGROUND AND AIMS

There is an unexplained association between ulcerative colitis [UC] and primary sclerosing cholangitis [PSC], with the intestinal microbiota implicated as an important factor. The study aim was to compare the structure of the intestinal microbiota of patients with UC with and without PSC.

METHODS

UC patients with PSC [PSC-UC] and without PSC [UC] were identified from biobanks at Oslo University Hospital, Foothills Hospital Calgary and Mount Sinai Hospital Toronto. Microbial DNA was extracted from colonic tissue and sequencing performed of the V4 region of the 16S rRNA gene on Illumina MiSeq. Sequences were assigned to operational taxonomic units [OTUs] using Quantitative Insights Into Microbial Ecology [QIIME]. Microbial alpha diversity, beta diversity, and relative abundance were compared between PSC-UC and UC phenotypes.

RESULTS

In all, 31 PSC-UC patients and 56 UC patients were included. Principal coordinate analysis [PCoA] demonstrated that city of sample collection was the strongest determinant of taxonomic profile. In the Oslo cohort, Chao 1 index was modestly decreased in PSC-UC compared with UC [p = 0.04] but did not differ significantly in the Calgary cohort. No clustering by PSC phenotype was observed using beta diversity measures. For multiple microbial genera there were nominally significant differences between UC and PSC-UC, but results were not robust to false-discovery rate correction.

CONCLUSIONS

No strong PSC-specific microbial associations in UC patients consistent across different cohorts were identified. Recruitment centre had a strong effect on microbial composition. Future studies should include larger cohorts to increase power and the ability to control for confounding factors.

Primary sclerosing cholangitis - the Norwegian experience

Research related to primary sclerosing cholangitis (PSC) has since 1980 been a major activity at the Oslo University Hospital Rikshospitalet. The purpose of this publication is to describe the development of this research, the impact of this research on the clinical handling of the patients, and finally to describe what we believe are the most urgent, remaining problems to be solved. During the early years, our research dealt primarily with clinical aspects of the disease. The concomitant inflammatory bowel disease (IBD) seen in most patients with PSC was a major interest and we also started looking into genetic associations of PSC. Prognosis, malignancy development and treatment with special emphasis on transplantation have later been dealt with. These activities has had impact on several aspects of PSC management; when and how to diagnose PSC and variant forms of PSC, how to handle IBD in PSC and how to deal with the increased rate of malignancy? The problems remaining to be solved are many. What is the role of the gut and the gut microbiota in the development of PSC? Do the PSC patients have an underlying disturbance in the bile homeostasis? And how does the characteristic type of fibrosis in PSC develop? The genetic studies have supported a role for the adaptive immune system in the disease development, but how should this be dealt with? Importantly, the development of malignancy in PSC is still not understood, and we lack appropriate medical treatment for our patients.

Fatigue in primary sclerosing cholangitis is associated with sympathetic over-activity and increased cardiac output

BACKGROUND & AIMS

Patients with primary sclerosing cholangitis (PSC) frequently highlight the impact of fatigue on their life quality. The study aims were to evaluate fatigue and its associations in PSC and investigate whether overt autonomic dysfunction contributes to the expression of fatigue.

METHODS

All PSC patients under active follow-up at a regional liver centre were sent disease- and symptom-assessment tools. Three control groups were utilized; unselected community controls, patients with inflammatory bowel disease (IBD) without PSC, and cholestatic controls with primary biliary cirrhosis (PBC). A representative subgroup of PSC patients and normal controls underwent formal autonomic assessment.

RESULTS

Symptom-assessment tools were returned by 40 non-transplanted patients. PSC patients had significantly worse fatigue than population controls (P = 0.005). Fatigue was significant compared to population controls whether or not patients had accompanying IBD, although was more marked in those with both PSC and IBD. In patients with PSC and IBD, fatigue severity and autonomic symptoms were significantly increased in those with prior significant surgical intervention. Clinically significant autonomic dysfunction was seen in 22.5% of PSC patients, and of those, 78% had significant fatigue. Neurally mediated hypotension was found in 60% of PSC patients compared to 8% in the control group. The PSC group had increased sympathetic activity and reduced parasympathetic activity.

CONCLUSION

Fatigue is a significant problem in a minority of PSC patients and appears to be associated with autonomic dysfunction. Fatigued PSC patients should be screened for autonomic dysfunction and targeting such dysfunction represents a potential approach to treatment which warrants further exploration.

Metal Zn(II), Cu(II), Ni (II) complexes of ursodeoxycholic acid as putative anticancer agents

The aim of the study was to evaluate the influence of metal [Zn(II), Cu(II), Ni(II)] complexes with ursodeoxycholic acid (UDCA) on the viability and proliferation of tumour and non-tumour cells. Cell lines established from retrovirus-transformed chicken hepatoma (LSCC-SF-Mc29) and rat sarcoma (LSR-SF-SR) as well as from human cancers of the breast (MCF-7), uterine cervix (HeLa), lung (A549) and liver (HepG2) were used as model systems. Non-tumour human embryo (Lep-3) cells were also included in some of the experiments. The investigations were carried out by the thiazolyl blue tetrazolium bromide (MTT) test, neutral red uptake cytotoxicity assay, crystal violet staining, double staining with acridine orange and propidium iodide and the colony-forming method. The results obtained revealed that: (1) UDCA and its metal complexes in the tested concentrations decreased (to a varying degree) the viability and proliferation of the treated cells in a time- and concentration-dependent manner; (2) chicken hepatoma (LSCC-SF-Mc29) cells were most sensitive to the cytotoxic and antiproliferative action of the compounds tested, followed by rat sarcoma (LSR-SF-SR) cells; (3) Cu‒UDCA and Ni‒UDCA were more effective against animal LSCC-SF-Mc29 and LSR-SF-SR cells, while Zn‒UDCA significantly decreased the viability and proliferation of human tumour cell lines; (4) applied independently, UDCA expressed lower cytotoxic/cytostatic activity as compared to metal complexes; and (5) the sensitivity of the non-tumour embryonic Lep-3 cells to the effects of UDCA and its metal complexes was comparable or even higher than those of the human tumour cells.

Deleterious effect of oltipraz on extrahepatic cholestasis in bile duct-ligated mice

BACKGROUND & AIMS

Oltipraz (4-methyl-5(pyrazinyl-2)-1-2-dithiole-3-thione), a promising cancer preventive agent, has an antioxidative activity and ability to enhance glutathione biosynthesis, phase II detoxification enzymes and multidrug resistance-associated protein-mediated efflux transporters. Oltipraz can protect against hepatotoxicity caused by carbon tetrachloride, acetaminophen and alpha-naphthylisothiocyanate. Whether oltipraz has hepato-protective effects on obstructive cholestasis is unknown.

METHODS

We administered oltipraz to mice for 5 days prior to bile duct ligation (BDL) for 3 days. Liver histology, liver function markers, bile flow rates and hepatic expression of profibrogenic genes were evaluated.

RESULTS

Mice pretreated with oltipraz prior to BDL demonstrated higher levels of serum aminotransferases and more severe liver damage than in control mice. Higher bile flow and glutathione secretion rates were observed in unoperated mice treated with oltipraz than in control mice, suggesting that liver necrosis in oltipraz-treated BDL mice may be related partially to increased bile-acid independent flow and biliary pressure. Oltipraz treatment in BDL mice enhanced α-smooth muscle actin expression, consistent with activation of hepatic stellate cells and portal fibroblasts. Matrix metalloproteinases (Mmp) 9 and 13 and tissue inhibitors of metalloproteinases (Timp) 1 and 2 levels were increased in the oltipraz-treated BDL group, suggesting that the secondary phase of liver injury induced by oltipraz might be due to excessive Mmp and Timp secretions, which induce remodeling of the extracellular matrix.

CONCLUSIONS

Oltipraz treatment exacerbates the severity of liver injury following BDL and should be avoided as therapy for extrahepatic cholestatic disorders due to bile duct obstruction.

Specific bile acids inhibit hepatic fatty acid uptake in mice

Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. We tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end, stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%.

CONCLUSION

The data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease.

Current consensus on the management of primary sclerosing cholangitis

Guidelines for the management of primary sclerosing cholangitis (PSC) have recently been published by both the European Association for the Study of the Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD). The current review focuses on the management of PSC, based on these guidelines. There is no established medical therapy for PSC. The role for UDCA in slowing the disease progression and improving survival is as yet unclear, and there are no specific recommendations for the general use of UDCA in this condition. Guidelines recommend that dominant bile duct strictures with significant cholestasis should be treated with biliary dilatation, with or without stenting. Prospective studies to define type, duration, optimal frequency and long-term effects of endoscopic therapy are needed. Liver transplantation is recommended for end stage disease and has excellent results. PSC patients with dysplasia in biliary brush cytology specimens should also be considered for transplantation. There is no evidence-based algorithm for the follow-up of PSC patients, but some regular investigations are recommended (surveillance colonoscopies in patients with IBD and ultrasound to detect gallbladder mass lesions).

Duct-to-duct biliary reconstruction in patients with primary sclerosing cholangitis undergoing liver transplantation

BACKGROUND

Reconstruction of biliary drainage after liver transplantation (LTx) in patients with primary sclerosing cholangitis (PSC) has been a matter of controversy. Over recent years, the traditional method of Roux-en-Y hepaticojejunostomy (RY) has been challenged by duct-to-duct (DD) biliary reconstruction.

METHODS

This study represents a retrospective review of biliary complications, patient and graft survival after LTx in PSC patients based on type of biliary reconstruction. Outcomes of DD reconstruction in this group of patients and non-PSC patients are compared.

RESULTS

A total of 53 primary LTx procedures were performed for PSC between August 2005 and July 2010. Seven patients were excluded because unexpected cholangiocarcinoma was found in the explants (n=3) or because they received partial livers (n=4). Biliary reconstruction was performed as DD in 18 patients and RY in 28 patients. There were no bile leaks. Anastomotic stricture occurred in two (11%) patients in the DD group and one (4%) in the RY group. Two (7%) patients in the RY group developed non-PSC intrahepatic strictures and one had recurrence of PSC. Rates of 1- and 3-year patient and graft survival in the RY and DD groups were 96.7% and 96.7%, and 100% and 94.5%, respectively. In a group of 34 randomly selected patients transplanted for a non-PSC diagnosis with DD reconstruction during the same period, the anastomotic stricture rate was 9% and 1- and 3-year patient and graft survival rates were 97.0% and 88.5%; differences were not significant.

CONCLUSIONS

Duct-to-duct biliary reconstruction at the time of LTx in selected PSC patients is both effective and safe, and shows outcomes comparable with those of RY reconstruction in these patients and those of DD reconstruction in non-PSC patients.

Langerhans' cell histiocytosis of the liver in adults

Among adults, liver involvement is relatively frequent in Langerhans' cell histiocytosis (LCH), even though it is often overlooked. In fact, the liver involvement may be missed in apparently localized LCH or when it is the sole site of involvement. We present 23 cases of liver involvement in LCH out of a cohort study of 85 adult patients included in the French Histiocytosis Study Group Registry. The most frequent clinical setting was multiorgan involvement (87% of our cases). The main histological pattern in liver LCH was sclerosing cholangitis (56% of the cases). The symptoms included hepatomegaly (48%) and/or liver biochemistry abnormalities (61%, including cholestasis associated with increased transaminases levels in 35% of cases, cholestasis only in 22% and increased transaminases levels only in 4% of the cases). Particularly suggestive of the diagnosis was the observation of biliary tree abnormalities through magnetic resonance imaging (MRI). The natural history of liver LCH fits into two stages: early infiltration by histiocytes and late sclerosis of the biliary tree. We found that liver involvement had a significant impact on survival. Thus we suggest that clinical and biological liver evaluation must be performed regularly onwards to screen every LCH adult patient from the time of the initial diagnosis. MRI and liver biopsy should be considered as soon as the data point to a possible liver localization. If this diagnosis is confirmed, we suggest a treatment with ursodesoxycholic acid, as in other cholestatic diseases, together with treatments specifically directed towards LCH. However, the ideal treatment of liver LCH remains to be found, and in advanced cases transplantation is the sole option.