Paediatric Rheumatology Flashcards
What are the different types of juvenile idiopathic arthritis? (5)
Systemic
Polyarticular
Oligoarticular
Enthesitis-related
Psoriatic
How does systemic juvenile idiopathic arthritis present? What is seen on blood tests?
AKA Still’s disease
Salmon-pink rash
High swinging fevers
Lymphadenopathy
Joint inflmmation+pain
Weight loss
SPlenomegaly
Raised ESR and CRP
Raised ferritin, raised platelets
What is the most important complication of systemic juvenile idiopathic arthritis?
Macrophage activation syndrome
Severe activation of the immune system
Causes an acutely unwell child, DIC, non-blanching rash
LOW ESR
How is juvenile idiopathic arthritis managed?
NSAIDs
Steroids
DMARDs
Biologics
What is Henoch-Scholein purpura and what are the four classic features?
A type of IgA vasculitis
- Purpura
- Joint pain
- Abdominal pain (GI haemorrhage, intussusception, bowel infarction)
- Renal involvement (IgA Nephritis - haematuria, proteinuria)
How is Henoch-Schonlein purpura diagnosed?
Need to exclude other more serious causes of purport - meningococcal septicaemia, leukaemia, ITP, HUS
Diagnosis = urine dip, U+E, BP
How is Henoch-Schonlein purpura managed?
Mainly supportive
What is Kawasaki disease and what are the features?
A systemic medium-sized vasculitis
Persistent high fever (more than 5 days)
Widespread erythematous maculopapular rash
Peeling skin on palms and soles
Strawberry tongue
Cracked lips
Cervical lymphadenopathy
Bilateral conjunctivitis
How is Kawasaki disease managed?
High dose aspirin (reduces risk of thrombosis)
IV immunoglobulins (reduces risk of coronary artery aneurysm)
What is a key complication of Kawasaki disease?
Coronary artery aneurysm
Needs monitoring with echos
A 15 year old girl has developed a rash on her face and hands. The rash is non-pruritic. She reports feeling weak and lethargic over the last two weeks. She has felt feverish but has not checked her temperature. She is otherwise well.
Which serological marker would be raised in this patient?
A. ANA
B. Anti B burgdorferi antibodies
C. Anti-double stranded DNA (dsDNA)
D. ASOT (anti-streptolysin O titre)
E. ESR
E. ESR: The rash is a malar rash with eyelid (heliotrope rash) involvement, characteristic of juvenile dermatomyositis (JDM). ~50% of patients with JDM are positive for auto-antibodies but they are myositis specific ones. Even with the the antibody profile, ESR is still most likely to be raised in an untreated patient
An 8 year old boy is brought into the A&E by his mother, who is very worried about a rash she has noticed on his legs. On further questioning, the boy has had coryzal symptoms over the last 3 days but otherwise feels well. His mother first noticed the rash this morning and has never seen anything like it before.
On examination there is a palpable purpuric rash across the back of his legs. Cardiovascular and respiratory examination is normal, his temperature is 37.6 and his abdomen and left knee are tender on palpation. Blood tests reveal an elevated CRP.
Which of the following is the next best investigation?
A. Urine dipstick
B. Blood cultures
C. Renal biopsy
D. Full blood count
E. Skin biopsy
A. Urine dipstick
This boy has a triad of purpura over the extensor surfaces of the lower limb, abdominal pain and arthritis. Along with an elevated CRP, this clinical picture is suggestive of Henoch-Schonlein purpura. It is important that urinalysis is performed and blood pressure is checked to monitor for signs of renal involvement (haematuria/proteinuria/nephritic syndrome/nephrotic syndrome)
Not E. skin biopsy:
A skin biopsy with immunofluorescence for IgA and C3 is gold-standard for the diagnosis of Henoch-Schonlein purpura, however is not usually performed, especially in children. The diagnosis can be made on clinical signs and the elevated CRP. Urinalysis should be performed to look for signs of renal involvement
what is the most common arthritis in children? what does it affect mostly?
reactive arthritis
-often affects ankles & knees
what are main non-infective differentials for children that have fevers for more than 5 days?
Kawasaki disease, Still’s disease, rheumatic fever and leukaemia.
what investigations for Still’s disease?
Antinuclear antibodies and rheumatoid factors are typically negative.
There will be raised inflammatory markers, with raised CRP, ESR, platelets and serum ferritin.
A key complication is macrophage activation syndrome (MAS), where there is severe activation of the immune system with a massive inflammatory response.
It presents with an acutely unwell child with disseminated intravascular coagulation (DIC), anaemia, thrombocytopenia, bleeding and a non-blanching rash. It is life threatening. A key investigation finding is a low ESR.
polyarticular JIA vs oligoarticular JIA:
Polyarticular JIA
Polyarticular JIA involves idiopathic inflammatory arthritis in 5 joints or more. The inflammatory arthritis tends to be symmetrical and can affect the small joints of the hands and feet, as well as the large joints such as the hips and knees. There are minimal systemic symptoms, but there can be mild fever, anaemia and reduced growth. Systemic symptoms are mild, unlike systemic onset JIA.
Polyarticular JIA is the equivalent of rheumatoid arthritis in adults. Most children are negative for rheumatoid factor and are described as “seronegative”. When rheumatoid factor is positive they are described as “seropositive”. Seropositive patients tend to be older children and adolescents and the disease pattern is more similar to rheumatoid arthritis in adults.
Oligoarticular JIA
This is also knowns as pauciarticular JIA. It involves 4 joints or less. Usually it only affects a single joint, which is described as a monoarthritis. It tends to affect the larger joints, often the knee or ankle. It occurs more frequently in girls under the age of 6 years.
A classic associated feature with oligoarticular JIA is anterior uveitis. Patients should be referred to an ophthalmologist for management and follow up of uveitis.
Patients tend not to have any systemic symptoms and inflammatory makers will be normal or mildly elevated. Antinuclear antibodies are often positive, however rheumatoid factor is usually negative.
management of JIA:
The management should be coordinated by a specialist in paediatric rheumatology, with a specialist multi-disciplinary team. The aim of treatment is to reduce inflammation within the joints, minimise symptoms and maximise function.
Medical treatment depends on the severity and response, and involves:
- NSAIDs, such as ibuprofen
- Steroids, either oral, intramuscular or intra-artricular in oligoarthritis
- Disease modifying anti-rheumatic drugs (DMARDs), such as methotrexate, sulfasalazine and leflunomide
- Biologic therapy, such as the tumour necrosis factor inhibitors etanercept, infliximab and adalimumab
JIA definition and types:
Juvenile idiopathic arthritis (JIA) refers to a condition affecting children and adolescents where autoimmune inflammation occurs in the joints. It is diagnosed where there is arthritis without any other cause, lasting more than 6 weeks in a patient under the age of 16. It has also been known as juvenile chronic arthritis and juvenile rheumatoid arthritis.
The key features of inflammatory arthritis are joint pain, swelling and stiffness.
There are a number of subtypes of juvenile idiopathic arthritis. Each has individual characteristics and is associated with different serology (blood tests). It is worth remembering five key subtypes:
- Systemic JIA
- Polyarticular JIA
- Oligoarticular JIA
- Enthesitis related arthritis
- Juvenile psoriatic arthritis
