Clinically, a diagnosis of juvenile arthritis is made if there is pain, swelling and stiffness in one or more joints in patients up to the age of 16 years.

It is found that JRA occurs to the extent of 30% in some population studies. It reportedly occurs in 1 in every 10,000 children every year. Although there are good descriptive series from different part of the country, there is a lack of accurate epidemiological data. The age of onset is often below 5 years and girls tend to be affected twice as frequently as boys.

Although there are many different types of juvenile arthritis, a logical process of assessment can often lead to proper diagnosis and management. The mode of onset, type of joint involvement, the other associated organ system involvement and the attendant systemic features like fever, rash, weight loss etc. can all help in ascertaining the diagnosis.

Juvenile idiopathic arthritis: Here, the dominating clinical feature is painful swelling and stiffness in the joints. Depending on the number of joints involved this disease is further divide into 3 main categories. Pauci-articular (if < 4 joints are involved), polyarticular (> 4 joints are involved) and systemic onset disease (high-grade fever, rash and often other organ system involvement).

Juvenile systemic lupus erythematosus: The disease is characterised by fever, rash on the face, hair loss, oral ulcers and arthritis. Kidney disease is an important complication, occurring in a proportion of patients.

Juvenile myositis: Here, the child presents with muscle pains, weakness and diffuse rash. The rash can also be characteristically localized to the eye lids and knuckles.