Acute Polyarthritis

Reactive arthritis (Reiter’s syndrome)
Crystal-induced, eg, gout, pseudogout
Infection, eg, gonococcal arthritis, endocarditis, hepatitis B, parvovirus B19, rubella or post-rubella vaccination
Connective tissue disease, eg, rheumatoid arthritis, systemic lupus erythematosus, scleroderma, Sjögren’s syndrome, adult Still’s disease