Flashcards in Juvenile Idiopathic Arthritis Deck (32)
What is juvenile idiopathic arthritis?
-Group of systemic inflammatory disorders affecting children below age of 16 years.
-The most commonly diagnosed Rheumatic disease in children.
What is juvenile idiopathic arthritis an important cause of?
Disability and blindness
What is the aetiology and pathogenesis of JIA?
-JIA is an auto-immune disease.
-Etiopathogenesis is multi-factorial and different from that of adult RA.
-Strong subset-specific genetic markers may affect immune response
What is the criteria for diagnosis of JIA?
Age of onset
Duration of disease
Presence of arthritis (Joint swelling or 2 of the following:)
-Painful or limited joint movement
When can subtypes of JIA be identified?
After 6 months
What are the 3 major subtypes of JIA?
-Systemic onset 20%
What clinical subtypes of JIA have recently been identified?
-Enthesopathy related arthritis
-Juvenile psoriatic arthritis: oligo or spondylo with psoriasis or potential psoriasis
-Others: unclassified under above criteria
How is pauciarticular JIA divided?
-Type I 25%
-Type II 15%
-Type III 15%
What is the classical presentation of type I pauciarticular JIA?
-Limp rather than pain
-Mainly LL joints
-Knee>ankle>hand or elbow (hip very rare)
-Irregular iris due to posterior synechiae
- +ve ANA
-Can be asymptomatic
How is pauciarticular JIA defined?
4 or less joints
What is the classical presentation of type II pauciarticular JIA?
-Primary aged boys (8-9)
-Limp due to LL affection
-Mainly LL joints: knee and ankle
-Hips may be affected early with rapid damage requiring THR
-Can develop AS or spondyloarthritis
Which individuals with type II pauciarticular JIA are categoreised as juvenile ankylosing spondylitis?
Those with HLA-B27 + back involvement
What is the classical presentation of type III pauciarticular JIA?
-Girls during childhood
-Asymmetric UL and LL arthritis
-FH of psoriasis
What can happen to those with extended oligoarthritis?
30% of these presenting with pauciarticular JIA can go on to more severe polyarticular course.
How is polyarticular JIA defined?
5 or more joints
What is the classical presentation of RF- polyarticular JIA?
-Girls of any age (often early)
-Constitutional manifestations (low grade fever, malaise)
-Symmetric large and small joints affection: knees, wrists, ankles, MCPs, PIPs, neck
What is the classical presentation of RF+ polyarticular JIA?
-Girls in later childhood (including teens)
-Constitutional manifestations (low grade fever, malaise, weight loss)
Iridocyclitis is rare
-Similar to adult RA
What can be seen on x-ray of RF+ polyarticular JIA?
Erosions which occur early
What can complicate RF+ polyarticular JIA?
How is systemic onset JIA defined?
Extra-articular features which start early and disappear after 2-5 years
What is another name for systemic onset JIA ?
What is the classical presentation of Still's disease?
-Occurs throughout childhood (4-6 years)
-Joints affected include wrists, knees, ankles, cervical spine, hips and TMJ
-Evanescent salmon red eruption on trunk and thighs accompanised by fever. Exhibits Koebner's phenomenon
What extra-articular features can be present in Still's disease?
-Tamponade and myocarditis
-Generalised non-tender lymphadenopathy
-Abdominal pain +- transaminases
Describe the associated fever of Still's disease.
-Rise to 39.5 C daily for at least 2 weeks
-Late in afternoon or evening and returns to normal or subnormal in the morning
-Child appears toxic with fever +/- chills but looks normal when fever goes away
What is the 1st line therapy for JIA?
What is the 2nd line therapy for JIA?
If no response to NSAIDs/ joint (steroid) injections.
(Rarely needed in oligoarticular JIA)
-Methotrexate (pharmocokinetics is age related).
-Anti-TNF Rx. (all 3): In methotrexate failure.
-IL-1 R-antagonist (Anakinra) in refractory systemic arthritis.
-IL-6 antagonist (Tocilizumab) for refractory systemic disease.
Why is there limited indications for systemic steroids?
Due to their serious side effects
What are systemic steroids used in?
-Systemic JIA (control pain and fever)
-Serious disease complications with any subtype e.g. periocordial effusion, tamponade, vasculitis, severe auto-immune anemia, severe aye disease
-As a bridge between DMARDs
-Children undergoing surgery
What are the risks of systemic steroid use?