Rheumatoid arthritis (RA) is characterised by chronic symatrical polyarthritis – meaning that it affects many joints and it affects them on both sides of the body.
It’s difficult to pinpoint the beginning stages of RA as it often starts with fatigue, and vague muscle and joint pain symptoms, until the appearance of the synovial inflammation is apparent. This may persist for weeks or months.
The onset of symptoms of RA is gradual and affects several joints, particularly those of the hands, wrists, knees and feet, which tend to become affected on both sides of the body. Sometimes a single joint will be inflamed.
About one in 10 people with RA will experience sudden onset of inflammation in many joints. Sometimes this is accompanied by a low-grade fever as it’s a systemic illness (i.e. the entire body is affected).
The main symptoms are stiffness, pain and tenderness in all inflamed joints that lasts longer than six weeks. Generalised stiffness is common and usually worse after periods of inactivity or immobilisation of a joint.
There is usually morning stiffness lasting more than one hour. The duration of morning stiffness can be used as a crude measure of the degree of inflammation, as it improves with treatment.
Symptoms may come and go
Inflammation of the synovium causes swelling, tenderness and limitation of motion. The joint may be warm to the touch, particularly the large joints.
Joint swelling results from accumulation of fluid within the synovial space, thickening of the synovium and thickening of the joint capsule. The inflamed joint may be held in a partly flexed position since this minimises pain.
Later, fixed deformities of the joints arise as a result of joint damage. The symptoms may come and go and a period of increased disease activity is called a "flare". This may last for days or months.
RA also affects many parts of the body besides the joints. It can cause eye problems and dryness of the mouth. Small lumps under the skin over bony areas can occur. These are called rheumatoid nodules. Inflammation and scarring of the lungs, inflammation of the blood vessels and anaemia can be present. In rare cases, RA could also cause inflammation of the membrane around the heart.
Reviewed by Dr Stella Botha, rheumatologist at Groote Schuur Hospital, Cape Town (MBChB, MRCP, PhD). November 2017
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