Seronegative rheumatoid arthritis is a diagnosis of rheumatoid arthritis (RA) in the absence of certain antibodies typically present in the patient’s blood. This form of RA, one of the two main types, is characterized by a negative test for rheumatoid factor (RF) and/or anti-citrullinated peptide antibodies (CPP).
The diagnosis of RA often involves blood tests. A positive anti-CCP and RF test suggests a strong likelihood of RA. Conversely, a positive anti-CCP but negative RF could indicate early-stage RA or a potential future development of the disease. If both anti-CCP and RF tests are negative, other tests may be necessary as RA cannot be confirmed.
One such test is the Erythrocyte Sedimentation Rate (ESR) test, where the rate at which red blood cells settle at the bottom of a test tube is measured. Another specific test for RA is the anti-CCP blood test, which is present in about 60-70% of RA patients. However, 10-15% of RA patients may have negative results in both tests, more commonly in cases with mild disease.
Other blood tests used in diagnosing RA include C-reactive protein (CRP), full blood count (CBC), and antinuclear antibodies. Rheumatoid arthritis, a chronic inflammation of the joints, affects approximately 1.3 million adults in the United States. Diagnosis can be challenging in early stages due to symptoms overlapping with other diseases, and there is no single test or physical finding to definitively confirm RA.
During a physical examination, doctors look for joint swelling, redness, and warmth as indicators of RA. For more detailed information, visit the American College of Rheumatology, Verywell Health, Rheumatoid Arthritis Blood Tests, Johns Hopkins Arthritis Center, Healthline, and Mayo Clinic.
