ACPA/CP4-3

The ACPA/CP4-3 test is a blood test used to detect the presence of anti-citrullinated protein antibodies (ACPA), which are commonly associated with autoimmune diseases like rheumatoid arthritis. These antibodies target proteins that have been modified by a process called citrullination, which is often seen in individuals with rheumatoid arthritis. A positive test result means ACPA are detected, suggesting the presence of rheumatoid arthritis or an increased risk of developing it, while a negative result means these antibodies are not present, making the condition less likely. This test helps doctors understand if the disease is active and monitor how well treatments are working.