Arthritis in children is not uncommon. Rheumatic problems in children account for 7%-8% of cases attending rheumatology clinics.
Juvenile rheumatoid arthritis is diagnosed as per the following criteria
1.Age of onset less than 16 years.
2.Arthritis in one or more joints defined as swelling or effusion, or the presence of two or more of the following signs : limitation of range of motion, tenderness or pain on motion, and increased heat.
3.Duration of disease of 6 weeks to 3 months.
4.Type of onset of disease during the first 4 to 6 months, classified as:
- Polyarthritis-5 or more joints.
- Oligoarthritis-4 or fewer joints .
- Systemic disease- Arthritis intermittent fever rheumatoid rash visceral disease (hepatosplenomegaly, lymphadenopathy, etc.)
5.Exclusion of other types of arthritis.
The diagnosis of JRA and its subtypes is almost entirely clinical. Investigations help very little; yet the following features can be noted:
- Raised ESR and C-reactive protein
- Leucocytosis with systemic disease
- Absent rheumatoid factor except in subtype 3 (b)
- Synovial fluid : Inflammatory with mainly polymorphs
Children with JCA, if untreated or poorly treated, can develop severe complications, some of which may be fatal, e.g. infections, renal failure, cardiopulmonary failure.
Many children develop involvement of the cervical spine. This can present as torticollis. It usually causes fusion of apophyseal joints and can lead to atlanto-axial subluxation, particularly in seropositive patients and juvenile spondylitis.