Carly Susan Gardner MD, Presenter: Nothing to Disclose

Rendon C. Nelson MD, Abstract Co-Author: Consultant, General Electric Company Consultant, Nemoto Kyorindo Co, Ltd Consultant, VoxelMetrix, LLC Research support, Bracco Group Research support, Becton, Dickinson and Company Speakers Bureau, Siemens AG Royalties, Wolters Kluwer nv

Mustafa Rifaat Bashir MD, Abstract Co-Author: Research support, Siemens AG Research support, Bayer AG

Daniele Marin MD, Abstract Co-Author: Nothing to Disclose

Lisa Mei-ling Ho MD, Abstract Co-Author: Nothing to Disclose

A recent study (AJR 2014 Mar;202(3):536-43) proposed specific imaging criteria for differentiating autoimmune cholangiopathy (IAC) from primary sclerosing cholangitis (PSC) or other biliary diseases. The purpose of this study was to determine the diagnostic performance of these imaging criteria for diagnosis of autoimmune cholangiopathy.

Medical records search between 10/2008-10/2013 identified 10 patients (8M, 2W, mean age 61, range 34-82) with clinically and biopsy proven IAC. Ten cases of PSC (5M, 5W, mean age 51, range 22-65) and 4 cases of primary biliary cancer (1M, 3W, mean age 63, range 56-69) were randomly selected for comparative analysis. Three blinded and fellowship-trained abdominal radiologists, (experience 7-25 years), reviewed either MRI with MRCP (n=17) or CT and ERCP (n=7) for the following imaging predictors of IAC: single wall bile duct thickness > 2.5 mm; continuous biliary involvement, gallbladder involvement, absence of liver disease, peribiliary mass, pancreatic and renal abnormalities. Each radiologist provided imaging-based diagnosis of IAC, PSC, or biliary malignancy and sensitivities and specificities were recorded. Association of each imaging predictor for IAC compared with non-IAC (PSC or primary biliary malignancy) was determined by using Fisher’s exact test, P < 0.05 to indicate a significant association.

For diagnosis of IAC, mean (range) sensitivity and specificity was 79% (70-90%) and 83% (78-86%), respectively. The strongest imaging predictors for distinguishing IAC vs. non-IAC were: pancreatic abnormalities: 73% vs. 9% (P, 0.001-0.01); continuous biliary involvement: 80% vs. 43% (P, 0.01-0.20); single wall bile duct thickness > 2.5 mm: 73% vs. 40% (P= 0.01-0.41); and absence of liver disease: 80% vs. 57% (P=0.17-1).

Imaging predictors of IAC demonstrate moderately high sensitivity and specificity for distinguishing IAC from PSC or biliary malignancy. Pancreatic abnormality demonstrated the most significant association with IAC. Single wall bile duct thickness, continuous biliary involvement, and absence of liver disease demonstrate trends towards association with IAC.

Pancreatic abnormalities, thickened bile duct wall, continuous biliary stricturing, and absence of liver disease favor a diagnosis of IAC. However, it remains difficult to distinguish IAC from PSC or biliary malignancy based on imaging features alone.

Gardner, C, Nelson, R, Bashir, M, Marin, D, Ho, L, Usefulness of Imaging Criteria for Distinguishing Autoimmune Cholangiopathy from Primary Sclerosing Cholangitis or Bile Duct Malignancy.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14005762.html