title: Clinical utility of the anti-CCP assay: experiences with 700 patients.
abstract: Our objective was to determine the frequency of antibodies to cyclic citrullinated peptides (CCPs) in a series of patients with a variety of rheumatic diseases. Seven hundred consecutive serum samples from patients at an outpatient clinic were tested for the presence of rheumatoid factor (RF) and anti-CCP. Clinical diagnosis, radiographic information, and other laboratory data were taken from patients' charts. The sensitivity and specificity of anti-CCP reactivity for the diagnosis of rheumatoid arthritis (RA) were 74.0% and 94.5%, respectively; the corresponding results for RF were 69.7% sensitivity and 81.0% specificity. Highest rates of false-positive RF tests were found in patients with SLE (18.3% vs. 12.7% CCP), Sjögren's syndrome (73.3% vs. 3.3% CCP), and a control group with chronic hepatitis (24.7% vs. 1.3% CCP). The detection of anti-CCP is useful for the diagnosis of RA because of its similar sensitivity but higher specificity compared with RF. Anti-CCP also helps to diagnose other inflammatory and noninflammatory diseases (especially connective tissue diseases) by reducing the rate of false-positive results in comparison with RF.
authors: Department of Medicine B, Münster University Hospital, Albert-Schweitzer-Strasse 33, D-48129 Münster, Germany.
authors: Ulrich
authors: U
authors: Sauerland
authors: Heidemarie
authors: H
authors: Becker
authors: Matthias
authors: M
authors: Seidel
authors: Heiko
authors: H
authors: Schotte
authors: Peter
authors: P
authors: Willeke
authors: Annette
authors: A
authors: Schorat
authors: Bernhard
authors: B
authors: Schlüter
authors: Wolfram
authors: W
authors: Domschke
authors: Markus
authors: M
authors: Gaubitz
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000276:immunology; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002956:Citrulline / Q000276:immunology*; D015331:Cohort Studies; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D006801:Humans; D009391:Nephelometry and Turbidimetry; D010044:Outpatient Clinics, Hospital; D010045:Outpatients; D010456:Peptides, Cyclic / Q000276:immunology*; D011859:Radiography; D012216:Rheumatic Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000276:immunology; D012217:Rheumatoid Factor / Q000097:blood; D012680:Sensitivity and Specificity
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D010456:Peptides, Cyclic; D002956:Citrulline; D012217:Rheumatoid Factor