Juvenile Chronic Arthritis

History

ref: Schaller J.G. "Chronic arthritis in Children - Juvenile Rheumatoid Arthritis" CORR 182:80-89, 1984
George Frederick Still (1897) ® First English language description of "Chronic Childhood Arthritis" - published while he was a registrar in paediatrics and pathology at The Hospital for Sick Children, Great Ormond St, London

Definition

A condition of chronic synovitis in children
Symmetrical or asymmetrical involvement may be seen and may involve DIP joints

Classification

Systemic illness (Stills' disease) 20%
Rh factor negative poly articular 25%
Rh factor positive poly articular (related to adult type RA) 5%
Pauciarticular arthritis assoc with ANA & chronic iridocyclitis 30-35%
Pauciarticular arthritis assoc with spondylitis & HLA B27 10-15%
Fewer than 20% have progressive destructive disease and these are usually the Rh positive or systemic onset patients

Systemic Onset: (Stills' Disease) ~ 20%

Stills Disease

Fever, malaise, arthritis, lymphadenopathy and hepatosplenomegaly
Male = Female (slight male predominance)

Clinically

High intermittent fevers for a number of weeks and shaking chills are frequently present
During febrile periods - characteristic evanescent rash
Myalgia, arthralgia and transient arthritis
can also have: Pleuritis and pericarditis are generally mild but occasionally severe
Abdo pain secondary to peritonitis or adenitis
Usually affects multiple joints in a symmetrical fashion
Usually present for months then ® remit but 50% have systemic recurrences
Iridocyclitis is not a feature

Bloods

almost all pts have leucocytosis (may be more than 50,000)
anaemia may be profound

Prognosis

25% go on to have chronic poly arthritis

Poly-articular Rh factor Negative disease: (~25%)

Strong female predominance

Clinically

Extra-artic manifestations are "low grade" and not as striking as in the systemic form
Most characteristically ® symmetrical poly arthritis of small jts of hands, feet, ankles, knees, elbows and in ~ 1/2 patients also neck, hips, shoulders and TMJ
Iridocyclitis and pericarditis are rare

Prognosis

Severe destructive arthritis occurs in 10-15%
Majority of patients ultimately do well

Poly-articular Rh factor positive: (~ 5%)

Females more than Males

Onset

usually in late childhood

Clinically

Childhood equivalent of adult RA
Nearly always have systemic arthritis
Subcutaneous nodules frequently seen
Rheumatoid vasculitis, Feltys syndrome (splenomegaly & neutropenia) or fibrosing pneumonitis may be associated
Iridocyclitis is not a feature

Prognosis

Severe destructive arthritis is common occurring in more than 50%

Pauciarticular arthritis associated with ANA & Iridocyclitis: (30 - 35%)

NB: Pauciarticular = less than 3 joints
Females more than Males

Onset

Usually young ( less than 5 years)

Clinically


Fewer joints involved
30-35% have chronic iridocyclitis with a potential for permanent eye damage. Need Slit lamp examination and follow up every 3/12 in the first years of disease
Chronic iridocyclitis sequelae ® posterior synechiae, band keratopathy, cataracts, secondary glaucoma, visual loss ® blindness
Rarely have hip involvement, do not have sacroiliitis or back involvement

Bloods

Nearly all children with chronic iridocyclitis are ANA +ve

Prognosis

May be long lasting but prognosis for joint function is good

Pauciarticular arthritis associated with HLA B27: (10 - 15%)

Male more than Female

Onset

Generally older ( more than 8 years)

Clinically

Peripheral pauciartic disease often affecting only lower limbs
Often have radiographic sacroiliitis
Iridocyclitis as seen in Ank Spond, Reiters may be seen

Prognosis

May ® Ank Spond or other spondylo-arthritic disease.

Investigations

Blood screens

leucocytosis and anaemia are common
Acute phase reactants ESR & CRP usually raised
ANA commonly found in JCA and associated with Pauciarticular Type I and iridocyclitis
HLA 27 associated with pauciarticular Type II and spondylo-arthropathies
HLA DR4 associated with Rh positive poly articular disease
HLA DR5,6 & 8 associated with pauciarticular disease Type I

X-Ray

Changes similar to those in the adult disease with juxta-articular osteoporosis and peri-articular bony erosions

Treatment

Similar principles to the treatment of the adult form
  • Control synovitis
  • Prevent deformity
  • Reconstruct
  • Rehabilitate

    Salicylates

    Safest and best for initial treatment
    Dose: 100mg / kg in 4 divided doses ® blood levels of between 20-30mg/dl
    Other NSAIDs (see anti-rheumatic drugs section)
    Disease modifying drugs eg Gold, penicillamine, hydroxy-chloroquine
    Dose: Gold ® 1mg / kg / week up to weight of 25kg
    Maintenance similar to adults
    Hydroxy-chloroquine ® monitor eye toxicity
    Penicillamine ? use in children

    Corticosteroids

    Usually only indicated for severe systemic disease or topical use for iridocyclitis and if unsuccessful ® systemic
    Physio and occupational therapy ® maintain joint motion, prevent deformity and maintain muscle strength. Encourage exercise and make use of night splints and functional braces.
    Avoid bed rest.

    Surgery

    Synovectomy plays a minor role in JCA but soft tissue release a major role in assisting to maintain ROM and prevent joint contracture
    Synovectomy for chronic swelling of 6/12 or more not controlled by medical means
    Epiphyseodesis for anisomelia a frequent sequel in knee mon-articular arthritis
    Soft tissue release about the hip and knee particularly, TJRs (custom prostheses) and cervical spine fusion
    Correction of microganthia can be performed in older children in concert with dental and oro/facial surgeons

    Complications

    Most recover good function some ® restriction of movement
    - Hips, knees and elbows may have FFD
    - In some cases hips and knees may be almost rigid
    TMJ ankylosis and stiffness of the cervical spine may make intubation difficult

    Growth defects

    Local
    local factors affecting growth include blood supply, muscle spasm, capsular distension/ contracture, invasive inflammatory synovium, tendon contractures +/- rupture, articular cartilage damage
    local disturbances of growth can result in
    1. overgrowth and increased bone age or
    2. undergrowth and bone shortening or
    3. torsional anomalies
    General retardation
    of growth aggravated by steroid therapy.
    Characteristic deformities
    external torsion of the tibia
    dysplasia of distal ulna
    underdeveloped mandible (microganthia)
    short neck and scoliosis
    Children less than 5 years ® osteoporosis and prone to fractures.

    Prognosis

    At least 75% of children with JCA eventually enter long remission without significant permanent joint damage

    Spondylo-arthropathies in Children

    Ank Spond, Reiters and reactive arthritis, bowel disease and psoriatic arthritis may present in childhood and often fulfil the diagnostic criteria for JCA