Rheumatoid arthritis, during the acute flare-up phase, can show an increase in C-reactive protein (CRP). After the condition has eased, there can be a significant decrease in CRP, which can initially be used to judge the recovery of the condition.

The onset of rheumatoid arthritis is somewhat associated with infection by Group A beta-hemolytic streptococci. Clinically, it primarily presents as migratory pain in the large joints of the limbs and generally does not cause joint deformities; this is an important marker for differentiating it from rheumatoid arthritis.

In the acute phase of rheumatoid arthritis, treatment is mainly symptomatic, predominantly using nonsteroidal anti-inflammatory drugs (NSAIDs) such as etoricoxib or diclofenac sodium sustained-release capsules to alleviate symptoms.