Imaging and estimation of the prognostic features of primary sclerosing cholangitis by ultrasonography and MR cholangiography

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.

High prevalence of small duct primary sclerosing cholangitis among patients with overlapping autoimmune hepatitis and primary sclerosing cholangitis

BACKGROUND

Overlap syndrome is a term used for overlapping features of autoimmune hepatitis and primary sclerosing cholangitis or primary biliary cirrhosis and for autoimmune cholangitis. We describe a high prevalence of small duct primary sclerosing cholangitis among patients with overlapping autoimmune hepatitis and primary sclerosing cholangitis.

METHODS

We sought to retrieve all patients with overlap syndrome between primary sclerosing cholangitis and autoimmune hepatitis in six university hospitals in Sweden. The revised autoimmune hepatitis scoring system proposed by the International Autoimmune Hepatitis Group was used to establish the diagnosis autoimmune hepatitis. Endoscopic retrograde cholangiography and/or magnetic resonance cholangiography were used to separate the primary sclerosing cholangitis cases diagnosed through liver biopsy into small and large primary sclerosing cholangitis. A histological diagnosis compatible with both autoimmune hepatitis and primary sclerosing cholangitis was required for inclusion.

RESULTS

26 patients fulfilled our criteria for histological overlap of autoimmune hepatitis and primary sclerosing cholangitis, 7 (27%) of which had small duct primary sclerosing cholangitis. The reliability of the diagnosis small duct primary sclerosing cholangitis was supported by a very close similarity between small and large duct primary sclerosing cholangitis patients in clinical and laboratory data, and by a poor response to immunosuppressive therapy in the small duct primary sclerosing cholangitis patients. Patients with large duct overlap syndrome had a good response to immunosuppressive therapy. In both groups, our limited experience from ursodeoxycholic acid was largely poor.

CONCLUSIONS

Small duct primary sclerosing cholangitis is prevalent in the overlap syndrome between autoimmune hepatitis and primary sclerosing cholangitis.

Sonographic detection of perihepatic lymphadenopathy is an indicator for primary sclerosing cholangitis in patients with inflammatory bowel disease

AIM

Primary sclerosing cholangitis (PSC) is a frequent complication in patients with inflammatory bowel disease (IBD). While hyperplasia of the perihepatic lymph nodes has been described in patients with PSC, its prevalence and cause in IBD patients remains obscure. In the present study we address the question of whether ultrasound (US) examination is useful to detect perihepatic lymphadenopathy and improve the diagnostic accuracy for PSC in patients with underlying IBD.

METHODS

A total of 310 consecutive IBD patients were prospectively evaluated by US for enlarged perihepatic lymph nodes, as well as serologic testing for cholestasis-indicating enzymes. In patients with positive test results, viral or autoimmune liver disorders were excluded by serum testing. Next, the presence of PSC was confirmed/excluded by endoscopic retrograde cholangiography (ERC).

RESULTS

Perihepatic lymphadenopathy was detected by US in 27 of 310 (9%) patients. In 9 (33%) of those, serologic testing identified an underlying autoimmune or viral hepatitis. In the remaining 18 patients, ERC confirmed PSC in 17 (94%) and excluded it in 1. Elevated cholestasis parameters were found in 43 of 310 (14%) patients and 5 (12%) of those were diagnosed with autoimmune or viral hepatitis. In the remaining 38 patients, ERC confirmed PSC in 15 (39%) and excluded it in 23 (61%). Therefore, when autoimmune or viral hepatitis was excluded, enlarged lymph nodes in US predicted PSC more accurately than conventional serum parameters alone (PPV 94 and 39%, respectively [ P<0.001]), and the sensitivity ratio increased by a factor of 1.13 in favor of the US examination.

CONCLUSION

In patients with IBD, detection of enlarged perihepatic lymph nodes is a highly predictive indicator for the presence of PSC. Alternative causes of perihepatic lymphadenopathy have to be excluded.

Pancreatic and biliary tract disorders in inflammatory bowel disease

Hepatobiliary disorders occur frequently in patients with IBD, with PSC and cholangiocarcinoma being the most clinically significant for endoscopists. Endoscopic therapy for PSC is effective in improving symptoms, biochemical parameters, and radiographic abnormalities. Endoscopic therapy may also confer survival benefit, but this has yet to be confirmed in randomized, controlled trials. Treatment should be restricted to those individuals with a rapid decline in liver function testing or those with recurrent cholangitis. Cholangiocarcinoma is a serious complication of PSC and carries an extremely poor prognosis. ERCP with brush cytology has a relatively low sensitivity and the diagnosis is usually made after the disease has become metastatic. Malignant biliary obstruction can be palliated by endoscopic stenting. Photodynamic therapy is a promising experimental technique that may confer symptomatic and survival benefit in patients with nonresectable, advanced cholangiocarcinoma. IBD patients also have an elevated risk for developing acute and chronic pancreatitis as well as pancreatic insufficiency. The majority of cases of acute pancreatitis are likely due to medication side effects and local structural complications of IBD. The remainder may possibly represent true extraintestinal manifestations of IBD. Chronic pancreatitis is frequently subclinical, but may be accompanied by clinically relevant exocrine insufficiency. ERCP is the test of choice for the diagnosis of chronic pancreatitis, but the role of endoscopy in the therapeutic management of IBD-associated chronic pancreatitis remains to be defined.

Sclerosing cholangitis

Primary sclerosing cholangitis in children can mimic autoimmune hepatitis in the absence of inflammatory bowel disease. Most adult patients have been identified with human leukocyte antigens that either predispose or protect against disease. Novel class I alleles and cytokine polymorphisms may also contribute to disease susceptibility. Primary alpha-hemolytic streptococci infection does not appear to directly cause primary sclerosing cholangitis. Promising diagnostic modalities such as single photon emission tomography require further study in comparison with cholangiographic techniques. Positron-emission tomography and DNA cytometry appear promising for confirming occult cholangiocarcinoma when present. The chemoprevention effects of ursodeoxycholic acid on colorectal dysplasia await further investigation. Initial results from high-dose ursodeoxycholic acid in halting disease progression, however, suggest a beneficial effect. In contrast, the impact of endoscopic therapy on natural history remains unresolved. Although liver transplantation continues to be effective for end-stage liver disease, disease recurrence in the allograft is a controversial topic.

The role of magnetic resonance cholangiopancreatography in patients with suspected biliary obstruction

Endoscopic retrograde cholangiopancreatography (ERCP) is an accepted and accurate procedure that combines the advantage of diagnosis of biliary obstruction with possible therapeutic endobiliary intervention. However, it is an operator-dependent and invasive procedure that is associated with complications and limitations. Magnetic resonance cholangiopancreatography (MRCP) is a unique noninvasive technique for the diagnosis of biliary obstruction. It is well suited to provide the information required to plan the optimal therapeutic approach for these patients. MRCP has the potential to replace or at least precede ERCP as the first-line imaging effort in the evaluation of suspected biliary obstruction. Significant advantages and some notable limitations inherent to the modality dictate its judicious use in appropriate circumstances. The present article reviews the utility of MRCP in evaluation of biliary obstruction, with brief reference to its principles and techniques.