Rheumatic Diseases and Conditions Evaluated by Rheumatologists
Click on the link associated with each condition to be directed to the American College of Rheumatology website or Disease Foundation website to learn more about the disease, diagnosis, and treatment, as well as gain access to many helpful resources.
Common Diagnostic Studies Used in the Evaluation of Rheumatic Diseases
Joint Fluid Aspiration
- RF (Rheumatoid Factor): Confers nonspecific risk of rheumatoid arthritis.
- ACPA (Anti-Citrullinated Protein Antibody): Confers specific risk of rheumatoid arthritis.
- ANA (Anti-Nuclear Antibody): Confers nonspecific risk of connective tissue disease.
- ANCA (Anti-Neutrophil Cytoplasmic Antibody): Confers risk of small vessel vasculitis.
- APLA (Anti-Phospholipid Antibody): Confers risk of antiphospholipid syndrome.
- C3 and C4 (Complement proteins 3 and 4): Low levels suggest active disease in lupus or related autoimmune diseases.
- UPCR (Urine Protein-to-Creatinine Ratio): High levels suggest active lupus nephritis or small vessel vasculitis.
- Uric acid: Elevated in people with gout but may be low during acute gout attack.
- ESR (Erythrocyte Sedimentation Rate): Nonspecific indicator of chronic inflammation.
- CRP (C-Reactive Protein): Nonspecific indicator of acute inflammation.
- CBC (Complete Blood Count): Used to assess the effects of autoimmune diseases and immunosuppressive medications on bone marrow function.
- CMP (Complete Metabolic Profile): Used to assess the effects of autoimmune diseases and immunosuppressive medications on kidney and liver functions.
- HLA-B27 (Human Leukocyte Antigen B27): Confers risk of spondyloarthropathy.
- HLA-B51 (Human Leukocyte Antigen B51): Confers risk of Behcet’s disease.
- Musculoskeletal Ultrasound: Used at point of care to assess joint inflammation, guide joint injection or joint fluid aspiration.
- XR: Used to assess joint damage from inflammation or wearing over time.
- CT or MRI: Used to assess joint, muscle, and blood vessel inflammation which are not visualizable on plain XR.
- Synovial Fluid Cytology: Used to test for crystals and blood cells in inflamed joints.
- Synovial Fluid Gram Stain and Culture: Used to test for infection in inflamed joints.