title: ANCA in haemodialysis patients.
abstract: The prevalence of positive ANCA as well as the prevalence of PR-3 and MPO antibodies were examined in a cross-sectional sample of 1277 haemodialysis patients from 16 German haemodialysis centres. We found 32 patients positive for c-ANCA (median titre 1:40; range 1:20-1:320) and 65 for p-ANCA (1:80; 1:20-1:1280). Twenty-two percent of the c-ANCA-positive and 31% of the p-ANCA-positive patients had PR-3 and MPO antibodies by ELISA respectively. Clinical evidence of vasculitis was found in 11 of 32 c-ANCA-positive and 19 of 65 p-ANCA-positive patients. Of the 11 c-ANCA-positive, four had a known diagnosis of Wegener's granulomatosis (WG); WG was recognized after the test in a further five patients and two had renal limited RPGN. Of the 19 p-ANCA-positive patients, three had a clinical diagnosis of microscopic polyarteritis (MP), MP was newly diagnosed in a further 12, WG in one and renal limited RPGN in three. The patients had not received cyclophosphamide (the diagnosis had been non-specified 'systemic disease'). Thus false-positive ANCA, as defined by absence of vasculitis, was found in 5% of dialysis patients versus 0% in patients with preterminal renal failure (n = 152) or blood donors (n = 150). Patients with vasculitis tended to have higher c-ANCA and p-ANCA titres respectively, but there was a considerable overlap. Titres were not higher in patients symptomatic at the time of examination (6 of 11 c-ANCA and 10 of 19 p-ANCA), but PR-3 and MPO ELISA were positive in all but two.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department Internal Medicine, Ruperto Carola University, Heidelberg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Weidemann
authors.forename: K
authors.initials: K
authors.lastname: Andrassy
authors.forename: E
authors.initials: E
authors.lastname: Ritz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies / Q000032:analysis*; D003430:Cross-Sectional Studies; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D053146:Myeloblastin; D009504:Neutrophils / Q000276:immunology; D009195:Peroxidase / Q000276:immunology; D006435:Renal Dialysis; D012697:Serine Endopeptidases / Q000032:analysis; D014657:Vasculitis / Q000276:immunology
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies; D009195:Peroxidase; D012697:Serine Endopeptidases; D053146:Myeloblastin