Acute polyarticular arthritis is most often due to the following: Infection (usually viral) Flare-up of a systemic inflammatory disorder Gout or calcium pyrophosphate arthritis (previously called pseudogout) Chronic polyarticular arthritis in adults is most often due to the following: Rheumatoid arthritis Seronegative spondyloarthropathy (usually ankylosing spondylitis, reactive arthritis, psoriatic arthritis, or enteropathic arthritis) Noninflammatory polyarticular pain in adults is most often due to the following: Osteoarthritis Chronic polyarthralgia in adults is caused most often by rheumatoid arthritis and osteoarthritis.