Juvenile Idiopathic Arthritis

Question 1

What is JIA?

Answer 1

Autoimmune, inflammatory arthritis
Idiopathic
Only affects yungers (<16)

Question 2

What is required for us to diagnose JIA?

Answer 2

Age of onset <16yrs
Duration >6wks
Symptoms:
Joint Swelling OR 2 of:
- Tenderness
- Painful/limited ROM
- Warmth

Question 3

There are 3 major subtypes of JIA (only determinable after 6 months)?

Answer 3

Pauciarticular (55%) - 4 or less joints
Polyarticular (25%) - 5 or more joints
Still’s disease (20%) - Systemic onset

Question 4

There are 3 subtypes of Pauciarticular JIA (Type 1, 2 & 3)

Describe the key features of each, particularly:

• typical presentee
• typical presentation (joint pattern etc)
• extra-articular manifestations

Answer 4

1) TYPE 1 (most common pauci)
- Female toddlers
- limp, not pain - mainly large LL joints
- chronic uveitis (eye)

2) TYPE 2…
- Older boys
- limp, pain - mainly LL joints
- Can feature hip/back pain which can rarely progress to ankylosing spondylitis (if +ve HLA-B27)
- iridocyclitis (eye)

3) TYPE 3…
- Girl (4:1) of any age
- asymmetric UL & LL arthritis
- dactylitis, iridocyclitis, psoriasis

-

Question 5

What are the subtypes of Polyarticular JIA?

Answer 5

RF -ve (15%)

RF +ve (10%

Question 6

What sets polyarticular apart from pauciarticular (other than more joints)?

What are the potential complications of polyarticular JIA?

Answer 6

Potential Systemic Symptoms:

• Low grade fever
• Malaise & weight loss
• Hepato-splenomegaly
• Mild Anaemia
• Growth abnormalities
• Nodules

Can be complicated by vasculitis, Sjogren’s or pulm fibrosis

Question 7

Whats special about how Still’s Disease (Systemic onset JIA) presents?

Answer 7

Systemic features start first with arthritis not occuring till 3-12 months in.

Question 8

Who gets Still’s Disease?

Answer 8

1.5F:1M, mostly 4-6yrs old

Question 9

How does Still’s Disease Start?

Answer 9

Fever.
It rises daily in the afternoon/evening for atleast 2 weeks.
Look for a child toxic with fever that goes away in the morning

Question 10

50-75% of Still’s Patients get Abdominal symptoms such as…

Answer 10

Hepatosplenomegaly
Abdo Pain
Raised Transaminases

Question 11

How many stills patients get lymph symptoms?

Answer 11

50-75% geet non-tender Generalised Lymphadenopathy

Question 12

90% of Still’s Patients present with a rash, descirbe it?

Answer 12

Evanescent Salmon Red Eruption on their trunk/thighs along with the fever.
It can be brought on by scratching (aka Koebner’s Phenomenon)

Question 13

Very rarely Still’s Patients can get pulmonary symptoms like..

Answer 13

Pleural effusion

Pulm. Fibrosis

Question 14

Inflammation of Serous membranes can come with Still’s Disease, what types are common?

Answer 14

36% of patient’s get Polyserositis including pericarditis

Rarely they can get tamponade and myocarditis

Question 15

How do the actual arthritis symptoms appear in Still’s Disease?

Answer 15

Start 3-12months after the fever onsets

Wrist, ankle, knee, C-spine, hips & TMJ

Question 16

What tests can we do to diagnose and determine the subtype of JIA?

Answer 16

1) ANA* (commonest in pauciarticular) & RF (subtype of polyarticular)
2) ESR/CRP (Most elevated in systemic onset)
3) FBC (May see anaemia, thrombocytosis & leucocytosis. Esp in polyarticular and Systemic onset)
4) Opthalmology screening for uveitis (mostly in pauciarticular)

*Anti-nuclear antibody

Question 17

1st Line treatment of JIA?

Answer 17

SImple Pain Killers
NSAIDs
Local Steroids:
- IA in Pauciarticular JIA
- For Eye disease

Question 18

What if NSAIDs & Steroids fail?

Answer 18

Methotrexate

Question 19

What if NSAIDs, steroids and MTX fail?

Answer 19

Anti-TNFalpha - Infliximab

Question 20

How do we treat Refractory Systemic Arthritis?

Answer 20

IL-1 Receptor Antagonist - Anakinra

IL-6 Antagonist (Tocilizumab)

Question 21

When would we risk using systemic steroids?

Answer 21

Systemic JIA
Serious compliated JIA e.g. pericardial effusion, tamponade, vasculitis, severe anaemia or severe eye disease
Bridge between DMARDs
Surgery

Question 22

What are the risks of systemic steroids?

Answer 22

Osteoporosis
Infection
GRowth Abnormality

Question 23

So summarise the likely presentations of Systemic Onset JIA?

Answer 23

1st = Daily rising and falling fever
2nd:
- Generalised Lymphadenoapthy
- Evanescent Salmon red rash
- ~ serositis
- ~ Abdo pain, hepatosplenomegaly & raised transaminases

Then 3-12months later the arthritis starts