Rheumatology Flashcards
What is JIA?
Juvenile Idiopathic arthritis
Commonest rheumatological condition in kids
Form of arthritis in <16yos that causes inflammation and stiffness of a joint for more than 6 weeks
What is the aetiology of JIA?
Genetic susceptibility - HLA association
Possibly triggered by viral/bacterial infection
What is the pathophysiology of JIA?
Autoimmune disease where there is chronic inflammation of the synovium with infiltration of immune cells and joint capsule hyperplasia leading to pannus formation and effusion of the joint cavity
What are the clinical features of JIA?
Arthritis for more than 6 weeks (swollen/painful joints)
Morning stiffness/gelling
Irritability/refusal to walk
School absence/limited ability to partake in physical activity
Rash/fever
Fatigue
Poor appetite/wt loss
Delayed puberty (due to ongoing inflammation)
What are your differential diagnoses for JIA?
Septic arthritis - child v. unwell, fever, raised inflammatory markers
OM - imaging will differentiate
Transient synovitis - child with runny nose, 3d later starts limping, settles in few days
Malignancies, e.g. lymphoma, neuroblastoma, bone tumours
Recurrent haemoarthrosis, e.g. haemophilia
Vascular abnormalities (e.g. AV malformation)
Trauma
What are the signs of JIA?
Swelling - periarticular soft tissue oedema/intraarticular effusion/hypertrophy of synovial membrane
Tenosynovitis
Pain
Joint held in position of maximum comfort (usually fixed flexion)
RoM limited
Oligoarthritis
<5 joints Large joints (e.g. knee) with no symmetry
Early onset (most common) - girls 1-5y
More likely to be ANA positive & get uveitis
Affects hands, knees, ankles, feet, wrists
Late onset - boys >8y
More likely to be ANA -ve with no extraarticular manifestations
More likely to affect hip
Polyarticular
5+ joints affected
Few/no systemic manifestations
Seropositive (RF+ve) - tends be girls >8
More likely to transition to adult with RA
Seronegative (RF-ve) - girls <5
Onset acute/insidious
Large, fast growing joints most affected
TMJ injury common –> limited bite & micrognathia
Systemic features rare but incl fever, slight hepatosplenomegaly, lymphadenopathy, pericarditis, chronic uveitis
Enthesitis-related JIA
Inflammation of enthesis + arthritis
2 of: Inflammatory spinal pain SI joint tenderness FH of enthesitis-related JIA Acute anterior uveitis HLA B27 positivity Onset of poly/oligoarthritis in boy >8y of age
NB pain is issue won’t necessarily see swollen joints
Psoriatic JIA
Chronic arthritis + definite psoriasis ALL HLA B27 +ve 2 of: Onchylosis (nail pitting) Dactylitis (swollen toes/fingers) FH of psoriasis
NB usually affects small joints of hand
Systemic JIA
Unwell Arthritis Intermittent fever >2 weeks - classical really high spike 1x/day with apyrexia between spikes Salmon pink erythematous rash Generalised lymphadenopathy Serositis Hepatomegaly/splenomegaly High inflammatory markers
What is pGAL?
Paediatric gait, arms and legs
Assess passive and active movement of all the joints assessing for pain, swelling and restrictions
What investigations can you do in JIA?
Labs (raised inflammatory markers, FBC, blood film)
XRay
USS
MRI with contrast (allows you to see the thickened synovium)
How do you Rx JIA?
NSAIDs
DMARDs - methotrexate (good for if poor response to IAS for oligo JIA, given s/c)
Biologics
Intra-articular steroids (good for olgioarticular JIA, induces remission in most by 6wks)
Oral steroids
Dietician input (address anaemia/generalised osteoporosis)
Physiotherapy
OT
What do DMARDs require?
Blood monitoring
