JUVENILE CHRONIC ARTHRITIS (JCA)
Approximately 1:1000 children will develop swelling of one or more joints persisting for more than 3 months with no specific cause found. 50% of these will progress to JCA.
Aetiology - unknown
Diagnostic Criteria
- Age under 16 at onset
- Persistent arthritis in one or more joints for 6 weeks (minimum) to 3 months after other aetiologies have been ruled out. E.g. infection, malignancy, blood dyscrasias, Reiter's, hypogammaglobulinaemia
Classification by onset (Schaller)
1. Systemic onset (Still's disease)
- Age: usually under 5years but can be any age
- Sex: <5yr female =" male;">5yr female > male
- Fever (high with spikes up to 40oC daily) plus one of the following
- Maculopapular rash
- Iridocyclitis
- RhF +ve
- Cervical spine involvement
- Pericarditis
- Generalised lymphadenopathy
- Hepatomegaly
- Splenomegaly
- Sites: knees, wrists, ankle, feet
2. Polyarticular onset
- Age: any, even before age 1year!
- Sex: female > male
- 5 or more joints involved in the first 3 months
- Seronegative (RhFactor -ve)
- Seronegative (RhFactor -ve)
Sites: knees (60%), wrists, hands
- RhFactor +ve
Older children (9-10 years) with persistent activity and rapid joint destruction affecting mainly the hands and feet.
3. Pauciarticular (most common)
- 4 or less joints involved in the first 3 months
- Type I
- Type I
Younger onset <6yr,>
- Type II
Older onset 9yr+, with males mainly affected. Association with HLA-B27.
Lab tests
HB | WCC | ESR | RhF | ANA | |
Systemic | - | ++ | ++ | +ve | +ve |
Polyarticular | + | + | + | -/+ve | 30%+ve (in those with RhF+ve) |
Pauciarticular | - | - | + or - | -ve | -ve (M) +ve (F) |
Radiological changes
- Early features limited to periarticular osteopenia
- Late features occur after 6 months and include growth disturbance, chondrolysis, joint destruction and erosions. These features are more common in the RhF +ve patients.
Prognosis
- 80% will eventually be able to lead normal functional lives.
- Death can occasionally occur in the systemic onset group because of infection or the development of amyloidosis.
- 60% if seen within 1 year of onset will have normal function at 5 years compared with 25% of those seen after 1 year.
- Functional outcome is related to joint contractures and destruction.
Poor prognostic factors
- Onset <>
- IgM (RhF) +ve
- Eye involvement
- Hip involvement leads to a greater functional deficit
Medical Management
- Aim: to suppress activity and therefore prevent joint deformity
- Multidisciplinary approach with rheumatologist, PT, OT, child psychologist etc
- PT to help prevent joint contractures and keep healthy muscles working. Hydrotherapy affective.
- OT for splints and orthoses
Drug treatment
- NSAID's
- Ibuprofen, voltarol, naproxen etc.
- Aspirin used to be the drug of choice but dangerous with children under the age of 5 years because of the risk of Reye's syndrome.
- Disease modifying drugs
- Methotrexate: shown to be effective in polyarticular disease
- Gold, penicillamine, azathioprine etc.
- Corticosteroids
- Systemic: the use of steroids does not affect the ultimate prognosis and there are many complications related to their use, in particular growth disturbance, adrenal suppression etc.
- Intra-articular/tendon sheath: can be effective in controlling flare ups
Surgical treatment
- Hip
- Soft tissue releases for contractures
- Total joint replacement
- Knee
- Soft tissue releases for contractures
- Synovectomy
- Epiphyseal stapling
- Supra-condylar osteotomy
- Total joint replacement (rarely needed)
- Foot and ankle
- Orthoses
- Triple fusion
Summary
Type | % | Joints | Features | Progression (%) |
Systemic (Still's) | 25 | many | Fever, rash, organomegaly | 25 |
Polyarticular: RhF -ve | 15 | many | Mild fever | 30 |
Polyarticular: RhF+ve | 15 | many | Severe joint destruction | 25 |
Pauciarticular I (F) | 30 | large | Iridocyclitis | 15 |
Pauciarticular II (M) | 15 | large | Spondylitis, HLA-B27 | 15 |
Other arthritides
- Juvenile psoriatic arthropathy
- Ankylosing spondylitis
- Reiter's disease
- Acute rheumatic fever
Tidak ada komentar:
Posting Komentar