Juvenile Idiopathic Arthritis Flashcards
How is juvenile idiopathic arthritis defined?
A group of systemic inflammatory disorders affecting children under 16 years
What are the 3 main aetiological factors for juvenile idiopathic arthritis?
Environmental
Genetic
Immunologic
What’s the prevalence of juvenile idiopathic arthritis in the UK?
Approx. 1 in 1000
What are the diagnostic criteria for juvenile idiopathic arthritis?
Age of onset <16
Duration of disease >6 weeks
Presence of arthritis - joint swelling or 2 of; painful or limited joint motion, tenderness, warmth
What are the 3 major subtypes of juvenile idiopathic arthritis?
Pauciarticular
Polyarticular
Systemic onset
How long does it take after diagnosis for a subtype to be identifiable?
6 months
What is the most common type of juvenile idiopathic arthritis?
Pauciarticular
What is pauciarticular juvenile idiopathic arthritis?
When 4 or less joints are involved
What are clinical features of type 1 pauciarticular JIA?
Presents before 5 years Much more common in girls Presents with limp rather than pain No general symptoms Mainly affects lower limb joints Chronic uveitis common Asymptomatic in half of cases Irregular iris
What are clinical features of type 2 pauciarticular JIA?
Age after 8-9 Boys much more common than girls Occassional general symptoms Limp Mainly lower limb Hip can be affected early with rapid damage - may evolve ankylosing spondylitis or sponyloarthritis
What are clinical features of type 3 pauciarticular JIA?
Any age during childhood
Girls:boys 4:1
Asymmetric upper and lower limb arthritis
Dactylitis
Family history of psoriasis in 40% of cases
What is Dactylitis?
Inflammation of a digit
What is polyarticular JIA?
JIA affecting 5 or more joints
What are clinical features of rheumatic factor negative polyarticular JIA?
Any age but often early Girls much more common than boys General symptoms - low grade fever, malaise Hepato-splenomegaly Mild anaemia Growth abnormalities Symmetric large and small joint
What is iridocyclitis?
Inflammation of the iris and ciliary body
What are clinical features of rheumatic factor positive polyarticular JIA?
Late childhood Girls much more common than boys General symptoms - Low grade fever, malaise, weight loss Anaemia Nodules Similar to adult RA Erosions in x-ray occur early
What is Still’s disease?
Systemic onset JIA
What defines Still’s from other forms of JIA?
Extra-articular features
What are clinical features of Still’s disease?
Most common 4-6years but can present throughout childhood
Girls about the same as boys
Fever of 39.5 for at least 2 weeks in late afternoon/evening returning to normal in the morning
Salmon red rash on trunk and thighs
Non tender generalised lymphadenopathy
Hepatosplenomegaly
Pericarditis
Potential pleural effusion or pulmonary fibrosis
Arthritis within 3-12 months of fever
What is uveitis?
Inflammation of the uvea
Why is uveitis important to keep in mind with JIA?
JIA is a common cause and it can potentially lead to blindness - can happen in any form of JIA
How is uveitis treated?
Steroids - topical/intraocular/systemic
Methotrexate
Anti-TNF
What is 1st line therapy for management of JIA?
Simple pain killers
NSAIDs - consider difference between half life in adults and children
What is 2nd line therapy for management of JIA?
If no response to NSAIDs - Methotrexate Anti-TNF IL-1 R-antagonist IL-6 antagonist
What is an example of an IL-1 R-antagonist?
Anakinra
What is an example of an IL-6 antagonist?
Tocilizumab
When are systemic steroids used in management of JIA?
Systemic JIA
Serious disease complications - vasculitis, auto-immune anaemia, etc
Bridge between DMARDs
Children undergoinng surgery
What are risks of systemic steroid use?
Osteoperosis
Infections
Growth abnormalities
What are non-drug forms of management for JIA?
Physiotherapy
Occupational therapy
When is intra-articular steroid use generally done?
Pauci-articular JIA
What are surgical treatments for JIA?
Synovectomy
Reconstructive/joint replacement surgery
What are localised growth failure problems in JIA?
Leg length discrepancies
Shortening of fingers, hands, forearms, toes, feet
Micrognathia
What is micrognathia?
Undersized jaw
What are generalised growth failure problems in JIA?
Short stature
Delayed puberty
Related to systemic steroid use and severe systemic disease
