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Flashcards in Juvenile Idiopathic Arthritis Deck (32)
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1

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.

2

What is juvenile idiopathic arthritis an important cause of?

Disability and blindness

3

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

4

What is the criteria for diagnosis of JIA?

Age of onset
-<16 years

Duration of disease
->6 weeks

Presence of arthritis (Joint swelling or 2 of the following:)
-Painful or limited joint movement
-Tenderness
-Warmth

5

When can subtypes of JIA be identified?

After 6 months

6

What are the 3 major subtypes of JIA?

-Pauciarticular 55%
-Polyarticular 25%
-Systemic onset 20%

7

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

8

How is pauciarticular JIA divided?

-Type I 25%
-Type II 15%
-Type III 15%

9

What is the classical presentation of type I pauciarticular JIA?

-Preschool girls
-Limp rather than pain
-Mainly LL joints
-Knee>ankle>hand or elbow (hip very rare)
-Chronic uveitis
-Irregular iris due to posterior synechiae
- +ve ANA
-Can be asymptomatic

10

How is pauciarticular JIA defined?

4 or less joints

11

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
-Enthesitis
-Can develop AS or spondyloarthritis

12

Which individuals with type II pauciarticular JIA are categoreised as juvenile ankylosing spondylitis?

Those with HLA-B27 + back involvement

13

What is the classical presentation of type III pauciarticular JIA?

-Girls during childhood
-Asymmetric UL and LL arthritis
-Dactylitis
-Chronic iridocyclitis
-FH of psoriasis

14

What can happen to those with extended oligoarthritis?

30% of these presenting with pauciarticular JIA can go on to more severe polyarticular course.

15

How is polyarticular JIA defined?

5 or more joints

16

What is the classical presentation of RF- polyarticular JIA?

-Girls of any age (often early)
-Constitutional manifestations (low grade fever, malaise)
-Hepato-splenomegaly
-Mild anemia
-Growth abnormalities
-Symmetric large and small joints affection: knees, wrists, ankles, MCPs, PIPs, neck
-Iridocyclitis rare

17

What is the classical presentation of RF+ polyarticular JIA?

-Girls in later childhood (including teens)
-Constitutional manifestations (low grade fever, malaise, weight loss)
-Anaemia
-Nodules
Iridocyclitis is rare
-Similar to adult RA

18

What can be seen on x-ray of RF+ polyarticular JIA?

Erosions which occur early

19

What can complicate RF+ polyarticular JIA?

-Sjorgen's
-Felty
-Vasculitis
-AR
-Pulmonary fibrosis
-AAS
-CTS

20

How is systemic onset JIA defined?

Extra-articular features which start early and disappear after 2-5 years

21

What is another name for systemic onset JIA ?

Still's disease

22

What is the classical presentation of Still's disease?

-F:M 1.5:1
-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

23

What extra-articular features can be present in Still's disease?

-Pleural effusion
-Pulmonary fibrosis
-Polyserositis
-Pericarditis
-Tamponade and myocarditis
-Generalised non-tender lymphadenopathy
-Hepatosplenomegaly
-Abdominal pain +- transaminases

24

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

25

What is the 1st line therapy for JIA?

-Simple painkillers
-NSAIDs

26

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.

27

Why is there limited indications for systemic steroids?

Due to their serious side effects

28

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

29

What are the risks of systemic steroid use?

-Osteoporosis
-Infections
-Growth abnormalities

30

When are local steroids used?

-Intra-articular mainly in Oligo-articular JIA
-Eye disease (ANA +ve oligo-articular disease