Localized rheumatologic diseases. Common diagnostic challenges.

Rheumatic pain is usually generalized, but in a variety of conditions it may present as localized and often remain so. These conditions include palindromic rheumatism, osteoarthritis, gout or pseudogout, seronegative spondyloarthropathy, septic arthritis, tendinitis and bursitis, radiculopathy and nerve entrapment, nodular growth, and tendon enlargement. When the presenting feature is focal pain in muscles, joints, or fibrous tissue, the differential diagnosis should include these considerations.