San Francisco, CA—Patients who present with joint pain and who have traveled recently may be infected with the chikungunya virus, which can closely mimic rheumatoid arthritis (RA). As the number of cases of chikungunya virus increases in the United States, rheumatologists and primary care physicians need to know how to distinguish between the virus and RA.
“Chikungunya was once thought to be a tropical disease, limited to the hotter parts of Africa and Asia. In the last 9 years, we have seen chikungunya break its geographic bounds. Cases are being reported in Europe and in the United States. Some patients develop persistent aches and pains that can easily be confused with rheumatoid arthritis or some other arthropathy. Arthritis caused by chikungunya can be a significant management challenge,” stated Arvind Chopra, MD, speaking at a clinical symposium during the recent American College of Rheumatology annual meeting.1,2 Dr Chopra is Director and Chief Rheumatologist at the Arthritis Research & Care Foundation, Center for Rheumatic Diseases in Pune, India.
Chikungunya is not endemic in North America (yet?). A history of recent travel to the Caribbean or Africa or other tropical climes can be a tipoff that the patient has chikungunya and not RA.
It is now known that the virus is transmitted by the Aedes aegypti mosquito, and, more recently, by the more cold-tolerant, Aedes albopictus mosquito. This additional vector appears to explain the recent geographic spread of the virus from the tropics into more temperate regions.
How to tell if a patient has chikungunya or RA? Symptoms are similar for both conditions—joint pain, muscle aches, fever, headache, fatigue, general malaise. However, symptoms of chikungunya come on rapidly, usually within 3 to 7 days after being bitten by an infected mosquito, whereas the onset of RA is typically more insidious.
The most clinically significant lab test difference between acute RA and acute chikungunya is the lack of autoantibodies in patients with the virus. However, some RA patients are also seronegative for these antibodies. Chikungunya patients almost never test positive for autoantibodies, however, and chikungunya also produces significant soft tissue damage. Patients with chikungunya often have edema in the hands and feet, heel pain, and pain around the wrists and ankles.
“The periarticular involvement can be another clue that we are dealing with chikungunya and not an autoimmune arthritis,” Dr Chopra explained.
Chikungunya has a similar clinical presentation to dengue fever, which has a similar geographic distribution because of common mosquito vectors. With chikungunya, the symptoms typically resolve within 2 to 3 weeks. Treatments include bed rest, fluids, and medications for pain and fever, such as ibuprofen, naproxen, acetaminophen, or paracetamol. Aspirin is not recommended.
Some patients have joint pain that persists for months, and it is not known what the best treatment is for those patients beyond symptomatic relief. “There are no randomized clinical trial data on the comparative effectiveness of different agents for longer-term treatment of chikungunya,” Dr Chopra said. Anecdotal evidence appears to support the use of methotrexate in post-chikungunya RA symptoms.
- Ryman K, Chopra A. Coming to a joint near you: chikungunya. Scientific session presented at: 2015 American College of Rheumatology Annual Meeting; November 7-11, 2015; San Francisco, CA.
- American College of Rheumatology. Chikungunya becomes more common in North America. Daily News: An Official Publication of the American College of Rheumatology. www.acrdailynewslive.org/chiku ngunya-becomes-more-common-in-north-america/.Published November 8, 2015. Accessed November 23, 2015.