{"id":2185,"date":"2024-12-06T05:10:44","date_gmt":"2024-12-06T05:10:44","guid":{"rendered":"https:\/\/suburban-blog.abymtech.com\/?p=2185"},"modified":"2025-03-05T10:18:34","modified_gmt":"2025-03-05T10:18:34","slug":"diagnosing-rheumatoid-arthritis-rheumatoid-factor-and-anti-ccp","status":"publish","type":"post","link":"https:\/\/www.suburbandiagnostics.com\/blog\/diagnosing-rheumatoid-arthritis-rheumatoid-factor-and-anti-ccp\/","title":{"rendered":"Diagnosing Rheumatoid Arthritis: Rheumatoid Factor & Anti-CCP"},"content":{"rendered":"

\"\"<\/p>\n

Rheumatoid factor (RF) is a reactive IgM autoantibody which is positive in approximately 80% of patients within one year of presentation of rheumatoid arthritis (RA), but in only 30% at the onset of arthritis.<\/p>\n

Anti-CCP (cyclic citrullinated peptide) is an autoantibody which appears early in the course of RA. When it is detected in a patient\u2019s blood, there is a high likelihood that the patient has RA.<\/p>\n

Anti-CCP has higher sensitivity and specificity than RF for diagnosis of RA.<\/b><\/p>\n\n\n\n\n\n\n\n\n
RF<\/b><\/td>\nAnti-CCP<\/b><\/td>\n<\/tr>\n
May be negative in early RA<\/td>\nOccurs years before clinical onset of arthritis<\/td>\n<\/tr>\n
Lower specificity (18.0%)*<\/td>\nHigher specificity (94.5%)*<\/td>\n<\/tr>\n
Lower sensitivity (69.7%)*<\/td>\nHigher sensitivity (74.0%)*<\/td>\n<\/tr>\n
Not a marker for disease progression<\/td>\nIndicates more aggressive and destructive form of disease and marker for disease progression<\/td>\n<\/tr>\n
Present in 5% normal individuals<\/td>\nElevated levels not seen in normal individuals<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

*Saureland U, Becker H, Seidel M, Schotte H, Willeke P, Schorat A et al. Clinical utility of the anti-CCP assay: experience with 700 patients. Ann N Y Acad Sci. 2005 Jun; 1050:314-8.<\/p>\n

Suburban Diagnostics performed a study using data from patients tested for RF and Anti-CCP together (for the diagnosis of RA) over the past 3 years.<\/p>\n