Post-infectious Arthritis and Related Conditions
In some instances, arthritis is not due to the direct invasion of the joint by the pathogen but rather to the immune response against the infectious agents. In this case, the eliciting infection precedes by a few weeks the onset of symptoms.
Acute rheumatic fever (ARF) is a classical post-infectious disease and arthritis is an integral part of its clinical picture (see Chap. 153, "Clinical Approach to a Child with Suspected Rheumatic Diseases"). Arthritis in ARF affects the large joints, is migratory, is characterized by pain, limitation of motion and limited joint swelling and is very sensitive to the treatment with non-steroidal anti-inflammatory drugs.
Post-streptococcal arthritis refers to a post-streptococcal syndrome characterized by an arthritis that is persistent rather than migratory, is less responsive to non-steroidal anti-inflammatory drugs, and occurs in patients whose illness does not fulfil