Rheumatoid arthritis (RA) is tested primarily through a combination of physical examination, blood tests, and imaging scans. There is no single definitive test for RA; rather, doctors use multiple indicators together to diagnose the condition.
Blood Tests
Several blood tests provide important information about RA:
- Rheumatoid factor (RF) test: Measures rheumatoid factor antibodies; high levels often indicate RA but can be present in other conditions or healthy people.
- Anti-cyclic citrullinated peptide (anti-CCP) antibodies test: Detects specific antibodies often present in RA, useful for early diagnosis and severity prediction.
- Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) tests: Measure levels of inflammation in the body, which are elevated in RA.
- Complete blood count (CBC): Assesses overall blood cell health and checks for anemia commonly associated with RA.
- Antinuclear antibody (ANA) test: Screens for autoimmune disorders that may mimic or coexist with RA.
Physical Examination
Doctors examine joints for swelling, tenderness, stiffness, and assess the range of motion. They inquire about symptom history and which joints are affected.
Imaging Scans
X-rays, ultrasound, or MRI scans may be performed to observe joint damage or inflammation to support diagnosis and monitor disease progression. Together, these assessments help confirm a diagnosis of rheumatoid arthritis and differentiate it from other conditions with similar symptoms.
