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GuidelinesPEML (Paeds Hospital STG)

Juvenile Idiopathic Arthritis (JIA)

Description Diagnostic criteria General and supportive measures Medicine treatment Referral ICD-10 code:  M08.0 DESCRIPTION Juvenile Idiopathic Arthritis (JIA) is of unknown origin with unexplained symptoms for at least 6 weeks with onset before the age of 16 years. Other causes of arthritis must be excluded, e.g. infections, malignancy, trauma, other autoimmune disease. Different clinical s

Description

Diagnostic criteria

General and supportive measures

Medicine treatment

Referral

ICD-10 code: M08.0

DESCRIPTION

Juvenile Idiopathic Arthritis (JIA) is of unknown origin with unexplained symptoms for at least 6 weeks with onset before the age of 16 years. Other causes of arthritis must be excluded, e.g. infections, malignancy, trauma, other autoimmune disease. Different clinical subgroups are recognised according to the pattern of onset that manifests within the first 6 months..

DIAGNOSTIC CRITERIA

Systemic onset JIA

  • Arthritis in one or more joints.
  • Plus at least 2 weeks of daily (quotidian) fever.
  • With one of the following:
    • erythematous macular rash, or
    • serositis, i.e. pericarditis and pleuritis, or
    • hepato- or splenomegaly, or
    • generalised lymphadenopathy.

Note:
There may be a prolonged delay between the onset of fever and the development of the arthritis.

Oligoarthritis

Always consider TB if only one joint is involved.

Arthritis affecting one to four joints for the first 6 months of disease.

  • Two categories are recognised:
    • Persistent oligoarthritis: affects < 4 joints throughout the disease course.
    • Extended oligoarthritis: affects > 4 joints after the first 6 months.
  • Occurs more commonly in girls than in boys.
  • Typically, onset is before 6 years of age.
  • Usually asymmetric arthritis that affects mainly large joints.
  • High risk of developing chronic iridocyclitis.
  • Up to 70% of patients are anti-nuclear antibody (ANA) positive.

Polyarthritis (Rheumatoid factor (RF)-negative)

  • Arthritis affecting  ≥ 5 joints in the first 6 months of disease.
  • Negative rheumatoid factor polyarthritis includes 2 subsets:
    • one that is similar to adult onset RF-negative rheumatoid arthritis, characterised by symmetric synovitis of large and small joints, onset at school age (between 10 and 14 years) and absence of ANA expression;
    • another that resembles oligoarthritis apart from the number of joints affected in the first 6 months of the disease. This subset of children usually presents between 2 and 5 years of age.

Polyarthritis (Rheumatoid factor (RF)-positive)

  • Arthritis affecting ≥ 5 joints in the first 6 months of disease.
  • Positive rheumatoid factor on 2 separate occasions at least 3 months apart.
  • Involves large and small joints.
  • Equivalent to RF-positive adult rheumatoid arthritis but with onset younger than 16 years of age.

Enthesitis-related arthritis

  • Arthritis and enthesitis

OR 

  • Arthritis or enthesitis, and 2 of the following:
    • sacroiliac joint involvement,
    • HLA-B27-positive,
    • first-degree relative with HLA-B27 associated disease,
    • arthritis in a boy after the age of 6 years,
    • anterior uveitis associated with pain, redness or photophobia.

Psoriatic Arthritis

  • Arthritis and psoriasis in a child,

OR

  • Arthritis and 2 of the following:
    • dactylitis,
    • nail pitting,
    •  psoriasis in a first-degree relative.

Undifferentiated arthritis

  • Arthritis not meeting criteria for one of the above categories or fitting more than one of the above groups.

Differential diagnosis

JIA is a clinical diagnosis and depends on the persistence of arthritis or typical systemic manifestations and by exclusion of other diseases:

  • Pyogenic and tuberculous joint infection and osteomyelitis.
  • Arthritis associated with other acute infectious illnesses.
  • Acute leukaemia and other malignancies.
  • Acute rheumatic fever.
  • Auto immune disorders, SLE or mixed connective tissue disease.
  • Reiter syndrome, i.e. arthritis, urethritis and conjunctivitis.
  • Arthritis associated with inflammatory bowel disease.

Investigations

Investigations must be tailored for each case; in consultation with a specialist, consider the following investigations:

  • Full blood count with differential and platelet count.
  • C-reactive protein and erythrocyte sedimentation rate.
  • Liver function screen before starting methotrexate.
  • Serum urea, creatinine and electrolytes.
  • Muscle enzymes, albumin, calcium, phosphate and alkaline phosphatase.
  • Auto-antibodies and rheumatoid factor.
  • X–ray or ultrasound of affected joints.
  • Arthroscopy and synovial biopsies in cases of possible TB arthritis.
  • Eye screen for uveitis.

GENERAL AND SUPPORTIVE MEASURES

  • Occupational and physiotherapy programs may provide the following:
    • exercises to increase range of movements of joints and to maintain muscle strength;
    • hot water baths, swimming pool exercises;
    • splints, e.g. nocturnal splints, for pain relief and prevention of contractures;
    • shoe inserts/raises;
    • aids for activities of daily living.
  • Orthodontic treatment if temporomandibular joints are involved.
  • All children should have a slit lamp examination initially, with follow-up thereafter, at the discretion of the ophthalmologist.
  • Explore individualised evidence-based non-pharmacological strategies for management of pain.

MEDICINE TREATMENT

There is no cure for JIA.

The goal of treatment is to eliminate active disease, to normalise joint function, to preserve normal growth, to prevent long-term joint damage and disease complications. Outcome is improved with early aggressive therapy. Treatment should be decided in consultation with a specialist.

Oligoarthritis

NSAID, e.g.:

  • Ibuprofen, oral, 10 mg/kg/dose 6-8 hourly.

LoE III1

NSAIDs as monotherapy are given for 1–2 months in patients with low disease activity and without joint contractures.

If no improvement:

ADD Intra-articular steroids.

  • Intra-articular corticosteroid injection for all active joints (rheumatologist or orthopaedic specialist):
  • Methylprednisolone acetate, 1 mg/kg with lignocaine 1%, 0.5 mL.
    • If no response: repeat in 3 months.
    • Young children may require light sedation with midazolam and ketamine.
    • Large joints, if possible, should be aspirated at same time.
    • Can be repeated after 3 months if there was an initial response, but the disease is not yet in remission.
    • Intra-articular steroids can also be used as initial therapy.

If disease activity still present after 3 months:
ADD

  • Methotrexate, oral, 10–15 mg/m2 /week as a single dose on an empty stomach. (Specialist initiated.)
    • Maximum dose: 25 mg/week.
    • Adverse effects include: nausea, mood changes, raised liver enzymes, bone marrow toxicity and proteinuria/haematuria.
    • Monitor: Pre-treatment FBC, liver transaminases and creatinine; then FBC and either ALT or AST 3 monthly. Serum creatinine 6 monthly.

PLUS 

  • Folic acid, oral, 5 mg weekly, (on the day after methotrexate) for the duration of the treatment.

If no remission in 6 months, refer to a rheumatologist.

Note:
Screen all patients early for uveitis (highest risk if ANA positive).

Polyarthritis – early

Start NSAID as soon as possible.

  • NSAID, e.g.:
    • Ibuprofen, oral, 10 mg/kg/dose 6-8 hourly.

LoE III1

If no significant improvement in 1 month, or if severe at onset, start disease-modifying drugs (DMARDs):

  • Methotrexate, oral, 10–15 mg/m2/week as a single dose on an empty stomach. (Specialist initiated)
    • Maximum dose: 25 mg/week.

PLUS

  • Folic acid, oral, 5 mg weekly (on the day after methotrexate) for the duration of the treatment.

Note:
Intra-articular steroids (IAS) may be used in conjunction with methotrexate.

For rapid relief of symptoms in severe early disease consider adding:

  • Prednisone, oral, starting dose: 1 mg/kg/dose once daily
    • Reduce dose gradually to 5 – 7.5 mg daily, depending on response.

Systemic onset JIA
 

Systemic JIA is an aggressive systemic disease. Refer to a rheumatologist early.

Initiate treatment after consultation with a rheumatologist.

  • NSAID, e.g.:
    • Ibuprofen, oral, 10 mg/kg/dose 6-8 hourly.

LoE III1

For patients with mild disease begin with:

  • Prednisone oral, 2 mg/kg as a single daily dose.
    • Once disease is controlled, reduce dose gradually.

Critically ill patients with internal organ involvement, such as pleuritis, pericarditis, myocarditis or evidence of early macrophage activation syndrome should be referred urgently:

  • Methylprednisolone, IV, 30 mg/kg/day (maximum 1 gram) for 3 days.

Follow with:

  • Prednisone, oral, 2 mg/kg as a single daily dose until disease is controlled.
    • These patients may respond to methotrexate or cyclosporine in the longterm, but the response is not as good as other JIA patients.

Psoriatic arthritis

Treat as for oligoarthritis if ≤ 4 joints, or polyarthritis if severe disease or >4 joints at onset.
Refer early as most children will require a DMARD.

Enthesitis related arthritis

Start NSAID as soon as possible.

  • NSAID, e.g.:
    • Ibuprofen, oral, 10 mg/kg/dose 6-8 hourly.

LoE III1

If severe disease:

  • Prednisone, oral, 1–2 mg/kg as a single daily dose for 2 weeks and wean over 2 weeks (in discussion with a rheumatologist).
    • Refer all children early for consideration of a DMARD therapy.

Uveitis management

Manage in consultation with an ophthalmologist.

Management of a flare of disease

  • NSAID, e.g.:
    • Ibuprofen, oral, 10 mg/kg/dose 6–8 hourly.

If severe flare, consider:

  • Prednisone, oral, 1–2 mg/kg daily.

Prompt referral to a subspecialist.

With residual pain not relieved by DMARDs, NSAIDs and corticosteroids, consult a specialist for appropriate management. Adopt a holistic multimodal pain management plan, see Pain Chapter.

REFERRAL

  • Urgent: uncontrolled systemic disease.
  • Paediatric specialist or subspecialist referral:
    • All for confirmation of diagnosis.
    • All patients requiring DMARD.
    • Adverse reaction to NSAID therapy.
    • Suspected JIA not responding to NSAID therapy.
  • Ophthalmology referral:
    • For slit lamp examination.
    • Patients with iridocyclitis and uveitis.
  • For orthopaedic treatment, e.g. where intra-articular corticosteroids are indicated, or if TB oligoarthritis is suspected.

Standard Treatment Guidelines And Essential Medicines List For South Africa, Hospital Level, Paediatrics, 2023 Edition

Chapter 12: Rheumatology And Vasculitides, 12.2 Juvenile Idiopathic Arthritis (JIA)

Drugs mentioned

NeoHealth® ID 17355 · updated 4/30/2023