The Anti-Cyclic Citrullinated Peptide (Anti-CCP) test is a highly specific blood test for diagnosing Rheumatoid Arthritis (RA), detecting autoantibodies that attack the body’s own joint tissues, helping doctors identify RA early, predict severe disease, and differentiate it from other arthritis types, with positive results suggesting a stronger likelihood of RA and potentially more aggressive disease progression, though a negative result doesn’t entirely rule out RA