Antibody to carbonic anhydrase II is present in primary biliary cirrhosis (PBC) irrespective of antimitochondrial antibody status. Clin Exp Immunol

Division of Internal Medicine, Ospedale San Paolo School of Medicine, Milan, Italy.
Clinical & Experimental Immunology (Impact Factor: 3.04). 01/1999; 114(3):448-54. DOI: 10.1046/j.1365-2249.1998.00735.x
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Antibody to carbonic anhydrase II, an enzyme abundantly present in biliary epithelium, has been proposed as a diagnostic marker for antimitochondrial antibody-negative PBC. In this study we determine its prevalence and clinical significance in a large series of patients with antimitochondrial antibody-positive and -negative PBC. Reactivity to carbonic anhydrase II was sought by Western immunoblotting in sera from 215 consecutive patients with PBC (26 antimitochondrial antibody-negative), 13 with autoimmune hepatitis, 25 with primary Sjögren's syndrome (pSS), 12 with systemic sclerosis, 19 with systemic lupus erythematosus and 73 healthy subjects. The prevalence of antibody to carbonic anhydrase II (titre 1:100) in PBC was 8%. No specific reactivity to carbonic anhydrase II was found in antimitochondrial antibody-negative PBC (7% versus 8% in antimitochondrial antibody-positive PBC). Ascites (P = 0.006) and Sjögren's syndrome (SS) (P = 0.022) in PBC were significantly associated with presence of the antibody. In patients with SS associated with PBC, the prevalence (19%) was similar to that observed in pSS (16%). At a serum dilution of 1:40, the prevalence of positive sera in PBC rose to 27% but disease specificity was reduced. Our findings in a large population of PBC patients rule out a relation between presence of antibody to carbonic anhydrase II and lack of antimitochondrial antibody. The higher prevalence of ascites found in positive patients warrants further evaluation.

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Available from: Pier Maria Battezzati, Oct 02, 2015
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    • "Anti-CAII autoantibodies are also found in autoimmune diseases such as systemic lupus erythematosus, Sjögren's syndrome, autoimmune cholangitis, chronic pancreatitis, primary biliary cirrhosis, endometriosis, systemic sclerosis, and type I diabetes {Taniguchi, 2003 #1371;Bataller, 2004#1348;Frulloni, 2000#1359;Itoh, 1992#1360;Alessandri, 2003#1372;D'Cruz, 1996 #1374;Invernizzi, 1998#380}. In all of these conditions, antibody levels of anti-CA II were higher in patients with disease than in the control group as reported from 3.8 – 10% in normal subjects. "
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