Pediatric Rheumatology Flashcards
What is the sex ratio of systemic onset of juvenile idiopathic arthritis?
About equal (1:1)
What is the age of onset of systemic onset juvenile idiopathic arthritis?
Can be any time in childhood, can also occur in adults
What is the pathogenesis of systemic onsite juvenile idiopathic arthritis?
It has a multifactorial disease caused by dysregulated innate immune response (autoinflammatory) to environmental stimuli leading to macrophage activation, T cell clonal expansion, and increased levels of IL-6, TNF-alpha, and IL-1
What polymorphisms contribute to systemic onset juvenile idiopathic arthritis?
Polymorphisms of IL-6, TNF, and IL-1 genes
What cytokines are increased in systemic onset juvenile idiopathic arthritis?
IL-6, TNF-alpha, and IL-1
What are the clinical signs of systemic onset juvenile idiopathic arthritis?
- Arthritis minimal at onset, in any joint, increasing in severity over time
- High spiking quotidian fever (1-2x daily)
- Rash
- Serositis (pericarditis, pleuritis)
- Generalized lymphadenopathy
- Hepatosplenomegaly
What inflammatory markers are found in lab results of patients with systemic onset juvenile idiopathic arthritis?
Leukocytosis, thrombocytosis, increased erythrocyte sediment rate (ESR), c-reactive protein (CRP), ferritin, d-dimers, polyclonal immunoglobulins
Are autoantibodies common in systemic onset juvenile idiopathic arthritis? Which ones?
No they are not common
What are the symptoms of macrophage activation syndrome?
Spiking fevers, enlarging liver and spleen, hemmorhage, CNS dysfunction
What lab results are suggestive of macrophage activation syndrome?
Dropping cell lines/Hb/platelets/WBCs, increasing TGs, decreasing ESR, hypofibrinogenemia, elevated d-dimers, extremely elevated ferritin
What pediatric disease is associated with macrophage activation syndrome?
Systemic onset juvenile idiopathic arthritis
What is the treatment for macrophage activation syndrome?
Cyclosporine (first IV, then oral), corticosteroids, anti IL-1
What is the therapy for systemic JIA?
- oral and IV corticosteroids
- immunosuppressive agents (methotrexate)
- biologics (IL-1, IL-6 antagonists, CTLA4 antagonists)
- calcium and vitamin D supplements
- treat disease complications
What demographics are at highest risk of Kawasaki disease?
- Asians at highest risk
- Male predominance
- Usually children under the age of 5
What is the pathogenesis of kawasaki disease?
Systemic necrotizing vasculitis with fibrinoid necrosis of medium-sized muscular arteries (especially coronary arteries) with inflammatory infiltrate into vessels, disruption of lamina elastica, and aneurysms
What are the three phases of Kawasaki disease?
Acute febrile (1-2 weeks)
Subacute (2-4 weeks)
Convalescent
What is the diagnostic criteria of Kawasaki disease?
Fever for more than 5 days plus at least 4 of the following:
- bilateral bulbar conjunctival injection
- oropharyngeal mucosal changes (injected and/or fissured lips, strawberry tongue, injected pharynx)
- changes in peripheral extremities (edema or erythema of hands or feet, periungual desquamation)
- polymorphous rash, primarily truncal, nonvesicular
- cervical lymphadenopathy with at least one node > 1.5 cm, usually unilateral
What lab results are associated with kawasaki disease?
- increased acute phase reactants (ESR, CRP)
- leukocytosis and anemia
- EKG and echocardiogram findings
What is the therapy for kawasaki disease?
IVIG and high dose aspirin as soon as possible
What is the prognosis of kawasaki disease?
Rare recurrence, low mortality, risk depends on level of coronary involvement
What populations are most susceptible to IgA vasculitis?
Mostly in children aged 3-15, slight male predominance, slight increase in cases in winter months
What is the pathogenesis of IgA vasculitis/henoch-schonlein purpura?
30-50% preceded by URI, IgA mediated dysregulation of immune response, may involve alternative complement pathway
What are the clinical signs of IgA vasculitis?
- Nonthrombocytopenic palpable purpura (dependent distribution, range in size, changes color)
- Subcutaneous edema
- GI manifestations
- Renal involvement (microscopic hematuria to mild proteinuria to renal failure)
- Scrotal pain and swelling
- Rarely CNS inflammation, pulmonary hemorrhage
What are the lab findings associated with IgA vasculitis?
Elevated IgA with mesangial or GI vasculature deposition, proteinuria, HTN, or renal crescents
What is the therapy for IgA vasculitis?
Hydration, bland diet, analgesia, reduction of intussusception, corticosteroids for GI/renal symptoms
What is the prognosis of IgA vasculitis?
Very good, fewer than 5% progress to renal failure
What demographics are most affectedby juvenile dermatomyositis?
Median age of onset is 7 years, but often presents lower. Female predominance (2:1). Usually preceding history of infection.
What are the diagnostic criteria for juvenile dermatomyositis?
Must have gottron papules or heliotrope rash plus multiple of the following:
- symmetric proximal muscle weakness
- elevated muscle enzymes
- characteristic electromyogram changes
- characteristic muscle biopsy findings (necrosis, perifascicular atrophy, perivascular mononuclear infiltrate)
What is the pathogenesis of juvenile dermatomyositis?
Frequently brought on by preceding illness, but can also be through UV light or other environmental factors
What HLAs are associated withjuvenile dermatomyositis?
HLA-B*08, DRB1*Q301,DQA1*0301
What are the clinical signs of juvenile dermatomyositis?
Rashes, weakness, pain, fever, dysphagia, difficulty speaking, abdominal pain, arthritis, calcifications, GI bleed
What muscle enzymes are high in juvenile dermatomyositis?
CK, AST, ALT, aldolase, and LDH
What lab findings besides muscle enzyme abnormalities are associated with juvenile dermatomyositis?
Nalifold capillary abnormalities, markers of immune and endothelial activation (neopterin, vWF antigen)
What are complications of juvenile dermatomyositis?
Decreased bone density (increased fractures), calcifications, partial lipodystrophy (associated with insulin resistant diabetes)
What is the therapy for juvenile dermatomyositis?
IV corticosteroid pulses, methotrexate, IV Igs, hydroxychloroquine, mixed response to biologics
What is Kawasaki disease?
Systemic necrotizing medium vessel vasculitis with coronary artery predilection, prominent fevers, and polymorphous rash
What is IgA vasculitis?
Self-limiting small vessel leukocytoclastic vasculitis characterized by palpable purpura and joint/GI/kidney disease
What is systemic JIA?
Systemic autoinflammatory disease characterized by arthritis, fever, and rash often with organ involvement
What is juvenile dermatomyositis?
Inflammatory proximal myositis with vasculopathy and characteristic gottronpapules and heliotrope rash
