Sclerosing cholangitis

Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare chronic cholestatic liver disease characterized by inflammatory destruction of the intrahepatic and/or extrahepatic bile ducts, leading to bile stasis, fibrosis, and ultimately to cirrhosis, and often requires liver transplantation (LT). PSC occurs more commonly in men, and is typically diagnosed between the ages of 30 and 40. Most cases occur in association with inflammatory bowel disease (IBD), which often precedes the development of PSC. PSC is usually diagnosed after detection of cholestasis during health evaluation or screening of patients with IBD. When symptomatic, the most common presenting symptoms are abdominal pain, pruritus, jaundice or fatigue. The etiology of PSC is poorly understood, but an increasing body of evidence supports the concept of cholangiocyte injury as a result of environmental exposure and an abnormal immune response in genetically susceptible individuals. PSC is a progressive disease, yet no effective medical therapy for halting disease progression has been identified. Management of PSC is mainly focused on treatment of symptoms and addressing complications. PSC can be complicated by bacterial cholangitis, dominant strictures (DSs), gallbladder polyps and adenocarcinoma, cholangiocarcinoma (CCA) and, in patients with IBD, colorectal malignancy. CCA is the most common malignancy in PSC with a cumulative lifetime risk of 10-20%, and accounts for a large proportion of mortality in PSC. LT is currently the only life-extending therapeutic approach for eligible patients with end-stage PSC, ultimately required in approximately 40% of patients. LT secondary to PSC has an excellent outcome compared to other LT indications, although the disease can recur and result in morbidity post-transplant.

Incidence and prevalence of primary sclerosing cholangitis in a defined adult population in Sweden

Population-based studies on the epidemiology of primary sclerosing cholangitis (PSC) are sparse. The aim of the present study was to investigate prevalence and temporal trends in the incidence of PSC 1992-2005 in an adult population in Västra Götaland, a region in southern Sweden with a defined population of about 1.5 million. Patients with PSC aged 18 years or above were identified through a computerized search for diagnostic codes. A total number of 199 incident cases fulfilling Mayo criteria for PSC were identified through retrospective validation of clinical records. Temporal trends in the incidence of PSC were investigated by Poisson regression and expressed as average annual percent change (AAPC) with a 95% confidence interval (CI). The point prevalence of PSC on December 31, 2005, was 16.2/100,000 in the total adult population (men, 23.7/100,000; women, 8.9/100,000). The annual incidence was 1.22/100,000 in the total adult population (men, 1.78/100,000; women, 0.69/100,000). The overall incidence rate of PSC increased significantly over the investigation period (AAPC 3.06, 95% CI 0.01-6.20). Stratified analysis revealed significantly increasing trends for inflammatory bowel disease (IBD)-associated PSC (AAPC 7.01, 95% CI 0.24-14.24) and large duct PSC (AAPC 6.32, 95% CI 0.03-13.02) in women and for PSC without IBD (AAPC 9.69, 95% CI 0.82-19.33) and small duct PSC (AAPC 17.88, 95% CI 0.95-40.25) in men.

CONCLUSION

This is the first study to report a significantly increasing trend in the incidence of PSC. The prevalence of PSC at the end of the study period is the highest reported to date. This implies that the medical burden of PSC may be higher than estimated previously.

Autoimmune pancreatitis/IgG4-associated cholangitis and primary sclerosing cholangitis--overlapping or separate diseases?

Autoimmune pancreatitis is a recently described fibroinflammatory disease which is characterised by raised serum levels of IgG4 (in >70% of cases), and an IgG4-positive lymphoplasmacytic tissue infiltrate. A favourable and rapid clinical response to oral steroid therapy is often seen. Biliary involvement is common, and the term IgG4-associated cholangitis has recently been coined. The cholangiographic appearances of IgG4-associated cholangitis and primary sclerosing cholangitis can be difficult to differentiate. Moreover, raised levels of serum IgG4 have been recently found in 9% of patients with primary sclerosing cholangitis (a much higher frequency than for other gastrointestinal diseases), and those with raised levels appear to progress more rapidly to liver failure. Here we review the similarities and differences between the biliary disease in autoimmune pancreatitis and primary sclerosing cholangitis, and address the issue of disease overlap. Improvements in understanding the relationship between these conditions might lead to an enhanced understanding of the aetiopathogenesis, and improved treatment of both conditions.

Clinical features and management of primary sclerosing cholangitis

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by inflammation and fibrosis of the bile ducts, resulting in cirrhosis and need for liver transplantation and reduced life expectancy. The majority of cases occur in young and middle-aged men, often in association with inflammatory bowel disease. The etiology of primary sclerosing cholangitis includes immune-mediated components and elements of undefined nature. No effective medical therapy has been identified. The multiple complications of primary sclerosing cholangitis include metabolic bone disease, dominant strictures, bacterial cholangitis, and malignancy, particularly cholangiocarcinoma, which is the most lethal complication of primary sclerosing cholangitis. Liver transplantation is currently the only life-extending therapeutic alternative for patients with end-stage disease, although recurrence in the allografted liver has been described. A PSC-like variant attracting attention is cholangitis marked by raised levels of the immunoglobulin G4 subclass, prominence of plasma cells within the lesions, and steroid responsiveness.

The burden of large and small duct primary sclerosing cholangitis in adults and children: a population-based analysis

OBJECTIVES

The epidemiology of primary sclerosing cholangitis (PSC) has been incompletely assessed by population-based studies. We therefore conducted a population-based study to determine: (a) incidence rates of large and small duct PSC in adults and children, (b) the risk of inflammatory bowel disease on developing PSC, and (c) patterns of clinical presentation with the advent of magnetic resonance cholangiopancreatography (MRCP).

METHODS

All residents of the Calgary Health Region diagnosed with PSC between 2000 and 2005 were identified by medical records, endoscopic, diagnostic imaging, and pathology databases. Demographic and clinical information were obtained. Incidence rates were determined and risks associated with PSC were reported as rate ratios (RR) with 95% confidence intervals (CI).

RESULTS

Forty-nine PSC patients were identified for an age- and gender-adjusted annual incidence rate of 0.92 cases per 100,000 person-years. The incidence of small duct PSC was 0.15/100,000. In children the incidence rate was 0.23/100,000 compared with 1.11/100,000 in adults. PSC risk was similar in Crohn's disease (CD; RR 220.0, 95% CI 132.4-343.7) and ulcerative colitis (UC; RR 212.4, 95% CI 116.1-356.5). Autoimmune hepatitis overlap was noted in 10% of cases. MRCP diagnosed large duct PSC in one-third of cases. Delay in diagnosis was common (median 8.4 months). A minority had complications at diagnosis: cholangitis (6.1%), pancreatitis (4.1%), and cirrhosis (4.1%).

CONCLUSIONS

Pediatric cases and small duct PSC are less common than adult large duct PSC. Surprisingly, the risk of developing PSC in UC and CD was similar. Autoimmune hepatitis overlap was noted in a significant minority of cases.

Chemotherapy-induced sclerosing cholangitis

AIM

To review the computed tomography (CT), magnetic resonance imaging (MRI) and cholangiographic findings of chemotherapy-induced sclerosing cholangitis (CISC).

METHODS

Between January 1995 and December 2004, 11 patients in the endoscopic retrograde cholangiography database were identified with CISC. Twelve CT, four MRI, 69 endoscopic and nine antegrade cholangiographic studies in these patients were reviewed. Serial change in appearance and response to endoscopic treatment were recorded.

RESULTS

CISC showed segmental irregular biliary dilatation with strictures of proximal extrahepatic bile ducts. The distal 5cm of common bile duct was not affected in any patient. CT and MRI findings included altered vascular perfusion of one or more liver segments, liver metastases or peritoneal carcinomatosis. Biliary strictures needed repeated stenting in 10 patients (mean: every 4.7 months). Cirrhosis (n=1) or confluent fibrosis (n=0) were uncommon findings.

CONCLUSION

CISC shares similar cholangiographic appearances to primary sclerosing cholangitis (PSC). Unlike PSC, biliary disease primarily involved ducts at the hepatic porta rather than intrahepatic ducts. Multiphasic contrast-enhanced CT or MRI may show evidence of perfusion abnormalities, cavitary liver lesions, or metastatic disease.