Doctors use blood tests to help monitor rheumatoid arthritis (RA), but these tests are only part of the full picture.

ESR and CRP are inflammation markers. When they are high, this means there is inflammation somewhere in the body, not necessarily only in the joints. They often go down when joint inflammation improves, but they can be normal even when RA is active, or high for reasons unrelated to RA, such as infections.

Complete Blood Count (CBC) checks hemoglobin, white blood cells, and platelets. Anemia is common in RA. Some medications may lower white blood cells, while platelets can increase with active inflammation.

Liver enzymes (ALT and AST) may rise mildly with some RA medications. This is usually temporary and monitored with repeat testing.

Kidney function is not affected by RA itself in most cases and is checked mainly in patients with risk factors or when using certain pain medications.

RF and Anti-CCP antibodies are used for diagnosis, not for follow-up. Their levels do not reflect disease activity and usually remain positive for life.