Juvenile rheumatoid arthritis

What is it?
Juvenile rheumatoid arthritis (JRA), sometimes known as Still's disease, is a chronic disease of the connective tissue that usually presents before age 16. It can cause joint and connective tissue damage and is the most common form of arthritis among children. There are several types of JRA; the number of joints involved and the results of certain blood tests, such as for rheumatoid factor, vary between these types.

Although it primarily appears as arthritis, JRA may also affect the heart and its lining, the lungs and their lining, the eyes and skin. About one-fifth of those with JRA have an enlarged spleen as well as joint inflammation.

JRA may begin with stiff and swollen joints that are painful. The affected child may have a low-grade fever and a rash. The cause is unknown, but it usually begins between the ages of 2 and 5 years or between 9 and 12 years. More girls than boys develop it, and it may be associated with a family history of the disease and recent rubella infection.

What tests are used?
Diagnosis of JRA is based on review of clinical signs and symptoms, such as persistent arthritis in one or more joints for at least 6 weeks that cannot be attributed to another cause. Patients may also have an enlarged liver or spleen, swollen lymph nodes, signs of anaemia, heart problems, and shortness of breath.

Laboratory tests that can help in the diagnosis, including ruling out other disorders, are:

Full blood count (FBC) – to detect anaemia;
Erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) – to detect inflammation;
Antinuclear antibody (ANA) – to detect the presence of antibodies;
Rheumatoid factor (RF) – may be positive or negative depending on the type of JRA;
CCP antibodies (cyclic citrullinated peptide antibodies) are rarely positive, though may predict disease severity;
Histocompatibility antigens (HLA) – may show the presence of antigens specific to autoimmune diseases; and
Synovial fluid analysis – may indicate the presence of inflammatory disease.

Other tests of diagnostic use include joint and chest X-rays to identify the presence of joint inflammation or fluid build-up around the heart or lungs, and ECG to detect inflammation of the heart.

What treatments exist?
JRA is a chronic illness that cannot be cured, but certain treatments can help to alleviate pain and maintain mobility and joint function, including physiotherapy, exercise, and some of the following medications: aspirin and non-steroidal anti-inflammatory drugs (NSAIDs); corticosteroids; mydriatics; liquid gold injections; penicillamine; chloroquine agents; and immune suppressing agents.