Which antibodies are detected in a rheumatoid arthritis (RA) test?

Anti-cyclic citrullinated peptide antibodies (anti-CCP) are specifically associated with rheumatoid arthritis (RA) and serve as a key marker in its diagnosis. The presence of these antibodies indicates an autoimmune response that is characteristic of RA, often appearing before clinical symptoms of the disease manifest. The test for anti-CCP antibodies is known for its high specificity for RA, making it a valuable tool in clinical practice for confirming the diagnosis.

In the context of other options, it is important to note that while anti-nuclear antibodies (ANA) can be present in various autoimmune diseases, their presence is not specific to RA and is more often associated with conditions such as systemic lupus erythematosus. Anti-streptolysin antibodies are typically related to infections caused by Streptococcus bacteria and do not pertain to RA. Antibodies against cytomegalovirus (CMV) indicate a viral infection but lack relevance in the context of rheumatoid arthritis. Therefore, anti-CCP is distinctly the most relevant antibody for diagnosing this particular condition, underlining its importance in rheumatology.