OBJECTIVES:
To determine the frequency of the antineutrophil cytoplasmic antibodies (ANCA), antiproteinase-3 and antimyeloperoxidase, in primary sclerosing cholangitis (PSC) with or without inflammatory bowel disease (IBD+ or IBD-) and in different types of autoimmune hepatitis (AIH). Additionally, to verify the agreement between ANCA patterns by indirect immunofluorescence and their antigenic specificities by ELISA.
METHODS:
For this study, 249 patients were enrolled (42 PSC/IBD+; 33 PSC/IBD-; 31 AIH type-1; 30 AIH type-2; 31 AIH type-3; 52 primary biliary cirrhosis; 30 healthy controls) whose serum samples were tested for ANCA autoantibodies.
RESULTS:
There were fewer female subjects in the PSC/IBD- group (p=0.034). Atypical perinuclear-ANCA was detected more frequently in PSC/IBD+ patients than in PSC/IBD- patients (p=0.005), and was significantly more frequent in type-1 (p<0.001) and type-3 AIH (p=0.012) than in type-2 AIH. Proteinase-3-ANCA was detected in 25 samples (only one with cytoplasmic-ANCA pattern), and more frequently in PSC/IBD+ than in PSC/IBD- patients (p=0.025). Myeloperoxidase-ANCA was identified in eight samples (none with the perinuclear-ANCA pattern). Among the 62 reactive samples for atypical perinuclear-ANCA, 13 had antigenic specific reactions for proteinase-3 and myeloperoxidase.
CONCLUSIONS:
PSC/IBD+ differed from PSC/IBD- in terms of sex and proteinase 3-ANCA and atypical perinuclear-ANCA reactivity, the latter of which was more frequently detected in type-1 and type-3 AIH than in type-2 AIH. There was no agreement between ANCA patterns and antigenic specificities in IBD and autoimmune liver diseases, which reinforces the need for proteinase-3 and myeloperoxidase antibody testing.
Antibodies; Antineutrophil Cytoplasmic; Autoimmune Hepatitis; Cholangitis Sclerosis; Inflammatory Bowel Diseases