A mosquito-borne virus that has spread to the Caribbean and Central and South America and has caused isolated infections in Florida often causes joint pain and swelling similar to that seen in patients with rheumatoid arthritis. Researchers at Washington University School of Medicine in St. Louis also found that blood tests of patients with the Chikungunya virus and those with rheumatoid arthritis can produce similar results. This may lead some patients with the virus to be misdiagnosed.
The findings, reported in the January issue of Arthritis and Rheumatology, underscore the need for doctors to obtain detailed travel and medical histories from patients being evaluated for rheumatoid arthritis. Such details could help distinguish between the two conditions.