May be caused by inflammation or infection of a joint capsule (arthritis), infection or inflammation of periarticular structures (tenosynovitis) or inflammation at the tendinous insertion of a bone (enthesitis).
Rheumatic disease is subdivided into three categories: inflammatory arthritis, non-inflammatory arthritis, and non-articular pain.
The most common type of inflammatory arthritis affects 1-2 joints include crystal induced disease, either gout or pseudogout, and joint infection.
Inflammatory arthritis is diagnosed by synovial fluid analysis.
The most common inflammatory arthritis affecting multiple joints is rheumatoid arthritis.
Other forms of inflammatory polyarthritis include psoriatic arthritis, and arthritis associated with inflammatory bowel disease.
Most cases of non-inflammatory arthritis whether monoarticular or polyarticular, are related to osteoarthritis.
The only appropriate rheumatology screening lab tests are acute phase reactants, either with erythrocytes sedimentation rate or C-reactive protein.
The above tests are almost always elevated in any inflammatory rheumatic disease.