FaridabadBy Dr B.C. Gupta, MD · 2026-11-01
Ask the Pathologist - MCQ of the Week. A short question to test how well you know common laboratory tests, with a plain-English explanation from Dr B.C. Gupta, MD (Pathology).
Q. Which blood test is more specific for rheumatoid arthritis than RA factor?
- A. Anti-CCP antibody
- B. HbA1c
- C. Dengue NS1
- D. Thyroid profile
Answer: Anti-CCP antibody
Anti-CCP antibody is more specific for rheumatoid arthritis than RA factor. It stands for anti-cyclic citrullinated peptide antibody. A positive anti-CCP result is more likely to point to rheumatoid arthritis rather than another condition, and the test can become positive early, sometimes before the joints are visibly affected. It is often requested together with RA factor rather than instead of it.
RA factor was the first blood test used for rheumatoid arthritis and is still requested regularly. It is less specific, because RA factor can also be present in other autoimmune conditions, in some long-term infections, and in a small number of healthy people, especially older adults. Neither test is perfect on its own: some people with rheumatoid arthritis have a negative RA factor and a negative anti-CCP, and some healthy people test positive.
HbA1c, dengue NS1 and a thyroid profile do not test for rheumatoid arthritis. HbA1c reflects average blood sugar over about three months, dengue NS1 is used when dengue is suspected, and a thyroid profile checks hormone levels. If your doctor has asked for an RA factor or anti-CCP test, call the centre to confirm preparation and timing before you visit.
