Juvenile Idiopathic Arthritis

Question 1

Diagnosis criteria

Answer 1

Age of onset <16 years 
Duration of disease >6 weeks
Presence of arthritis - joint swelling or 2 of:
- painful or limited joint movement
- tenderness
- warmth

Question 2

Subtypes of JIA

Answer 2

Pauciarticular (most common) - types I-III
Polyarticular - -ve RF & +ve RF
Systemic onset - least common

Can be identified after 6 months

Question 3

Investigations for JIA

Answer 3

ESR - elevated in systemic
ASO - often elevated
Rheumatoid factor (20% of late onset poly)
Anti-nuclear antibody (60% of pauci)

Question 4

First line treatment of JIA

Answer 4

Simple pain killers

NSAIDs

Question 5

Next line treatments of JIA

Answer 5

2. Joint steroid injections
3. Methotrexate
4. Anti-TNFa
5. IL-1 R antagonist (Anakinra) - refractory systemic disease
6. IL-6 antagonist (Tocilizumab) - refractory systemic arthritis

Question 6

Indications for systemic steroid use in JIA

Answer 6

Systemic JIA to control pain and fever
Serious complications
Bridge between DMARDs
Undergoing surgery

Question 7

Indications for local steroid (intra-articular) use in JIA

Answer 7

Main Rx fo oligo-articular JIA 
Eye disease (ANA +ve oligo-articular disease)

Question 8

Non-pharma treatment of JIA

Answer 8

PT

OT

Question 9

Surgical treatment of JIA

Answer 9

Synovectomy

Reconstructive / joint replacement

Question 10

Type I pauciarticular JIA presentation

Answer 10

Peak age 1-3
GIRLS
Presents as a limp and gait problems rather than pain, mainly in LL joints (knee>ankle>hand or elbow)
+ANA common
Chronic uveitis
Irregular iris due to posterior synechiae
Can lead to blindness if not treated

Question 11

Type II pauciarticular JIA presentation

Answer 11

Peak age >8
BOYS
Presents with limp due to LL affection (knee, ankle)
Hip can be affected early with rapid damage and enthesitis + AS, can mean that a THR is needed early
Acute iridocyclitis

Question 12

Type III pauciarticular JIA presentation

Answer 12

Can occur throughout childhood
GIRLS
Presents with asymmetric UL and LL arthritis, can be very destructive
Dactylitis
Many have FH of psoriasis, and can develop it later
Chronic iridocyclititis

Question 13

RH-ve polyarticular JIA presentation

Answer 13

Less aggressive form 
Can occur at any age but often early 
GIRLS
- Constitutional manifestations (low-grade fever, malaise)
- Anaemia
- Hepatosplenomegaly 
- Growth abnormalities 
- Symmetric large and small joints affected

Question 14

RF+ve polyarticular JIA presentation

Answer 14

More aggressive 
Late childhood 
GIRLS 
Similar to adult RA
- Constitutional symptoms (low-grade fever, malaise, weight loss)
- Anaemia 
- Nodules 
Erosions of x-ray

Question 15

Presentation of systemic onset JIA

Answer 15

Occurs throughout childhood (age 4-6 most)
Defined by extra-articular features - start early and disappear
- Fever: >39.5C daily for >2 weeks - rises late in afternoon and returns to normal by morning
- Rash: salmon red eruption on trunk and thighs, can be brought on by scratching (Koebner’s phenomenon)
- Lymph nodes: generalised, non-tender
- Serositis: polyserositis, pericarditis
- Abdo: hepahosplenomegaly, abdo pain, transaminases
- Pulmonary: pleural effusion, pulmonary fibrosis (rare)
- ARTHRITIS: within 3-12 months of fever onset, in wrists, knees, ankles, C-spine, hips, TMJ (75%)