Rheumatology Flashcards
What is the most common chronic rheumatological disease in children?
Juvenile idiopathic arthritis
What is the incidence of JIA?
2-23 per 100,000
Why does JIA occur?
- Not completely understood
- Genetic susceptibility
- Immune response
- Release of pro-inflammatory markers including TNF, interleukin 1+2
- Presence of antibodies
How do children with JIA present?
- Arthritis for at least 6 weeks
- Morning stiffness or gelling
- Irritability or refusal to walk in toddlers
- School absence or limited ability to participate in physical activity
- Rash /fever
- Fatigue
- Poor appetite/wt loss
- Delayed puberty
What is the differential diagnosis for JIA?
- Septic arthritis
- Osteomyelitis
- Transient synovitis
- Malignancies i.e lymphoma, neuroblastoma, bone tumours
- Recurrent haemarthrosis
- Vascular abnormalities
- Trauma
- Others
What are the signs of JIA?
- Swelling: periarticular soft tissue oedema, intraarticular effusion, hypertrophy of synovial membrane
- Tenosynovitis (swollen tendons)
- Joint held in position of maximum comfort
- Range of motion limited at extremes
What classification system is used for JIA?
ILAR classification
What types of JIA are there?
- Polyarticular
- Oligoarthritic/Pauciarticular
- Psoriatic
- Enthesitis-Related
- Systemic
What is oligoarthritic/pauciarticular JIA?
- 4 or fewer joints
- Large joints and asymmetrical
What are the 2 types of oligoarhr JIA?
- Early childhood onset (more common)
- Late childhood onset
Who does early childhood onset oligoarthritic JIA usually affect?
Girls aged 1-5
Who does late childhood onset oligoarthritic JIA usually affect?
Boys over 8
What are the features of late childhood onset oligoarthritic JIA?
- Test negative for ANA
- No extra-articular manifestation
- Hip involvement
What are the features of early onset oligoarthritic JIA?
- 20-30% develop uveitis
- Test positive for ANA
- Joints commonly affected include: knees, ankles, hands, feet and wrists
- No hip involvement
What is polyarticular JIA?
- 5 or more joints affected
- Few or no systemic manifestations of disease
What are the 2 types of polyarticular JIA?
- Seronegative (20-25%)
- Seropositive (5-10%)
Who is usually affected by seronegative polyarticular JIA?
Girls under 5
Who is usually affected by seropositive polyarticular JIA?
Girls over 8
What are the features of polyarticular JIA?
- Tempomandibular joint injury is common leading to limited bite and micrognathia
- Systemic manifestations are rare but can include fever, slight hepatomegaly, lymphadenopathy, pericarditis and chronic uveitis
- Onset can be acute but mostly insidious
- Large fast growing joints are mostly affected
What is enthesitis-related JIA?
Inflammation of the enthesis along with arthritis
What is the criteria fro enthsitis-related JIA?
2 or more
- Onset of oligoarthritis/polyarthritis in a boy >8 years
- HLA B27 positive
- Acute anterior uveitis
- Inflammatory spinal pain
- Sacroiliac joint tenderness
- FMH
What is psoriatic JIA?
Chronic arthritis and definite psoriasis is evident
What is always positive in psoriatic JIA?
HLA B27
What is the criteria fro psoriatic JIA?
2 or more:
- FMH
- Dactylitis: finger or toe swelling
- Onycholysis: nail pitting
What proportion of JIA does systemic JIA account for?
5-15%
How does systemic JIA present?
- Child unwell
- Arthritis
- Intermittent fever > 2 weeks (spikes once a day)
- Salmon pink erythematous rash
- Generalised lymphadenopathy
- Serositis
- Hepatomegaly/splenomegaly
- High inflammatory markers
How is JIA diagnosed?
History
Physical examination findings
-pGALS
Investigations
- Labs
- Plain x-ray
- US
- MRI with contrast
What does pharmacological treatment of JIA include?
- NSIADs
- DMARDs
- Biologic agents
- Intra-articular and oral steroids
What non-pharmacological management is there for JIA?
- Counselling for patients and parents
- School adjustments (including PE)
- Nutrition (to address anaemia and osteoporosis)
- Physiotherapy
- Occupational therapy
How effective are intra-articular steroids?
- Highly efficacious
- Remission >6 months in 84%
- Greater success in oligoarthritis JIA
- Safe and effective
- No long term side effects
What is the DMARD of choice?
Methotrexate
When are DMARDs used in JIA?
- Usually in poor response to IAS in oligo JIA
- They are commonly used (not many side effects)
When should DMARDs be used?
Early for good outcome
How are DMARDs given?
Injectable SC form
What is necessary when on DMARDs?
Blood monitoring
When are biologic agents used?
When there is failure to respond to DMARDs
What biologics are commonly used?
Anti-TNF agents
What can uveitis associated with JIA progress to if left untreated?
- Chronic uveitis
- Cataracts, glaucoma and blindness
How is uveitis complications prevented in JIA?
- All children diagnosed with JIA undergo regular screening
- Early detection prevents complications
When is uveitis more common?
In ANA positive oligo JIA
How does uveitis present?
- Normally <5 years
- Rarely symptomatic (incidental finding at screening)
- Red eyes, headache and reduced vision
How are children examined for uveitis?
Slit light examination
How is uveitis treated in JIA?
- Initially topical steroids to reduce inflammation
- More severe need systemic steroids
- Poor response to steroids then DMARD and biologics
When are children with JIA screened for uveitis?
- Should be seen within 6 weeks of diagnosis
- High risk children screened more often
What are the possible complications of JIA?
- Poor growth
- Localised growth disturbance
- Micrognathia
- Contractures
- Ocular complications