JRA and pediatric rheumatology Flashcards
What abnormalities might cue you in to a child with MSK problems?
Growth abnormalities, secondary sex characteristics delayed
How do you diagnose benign juvenile hypermobility syndrome?
beighton score positive @ >5/9
Definition of juvenile idiopathic arthritis
chronic arthritis in joint for > 6 weeks in pt under age 16
What are 3 types of JIA
pauciarticular polyarticular systemic
Describe clinical features of JIA subgroups: pauci, oligoarticular, and diffuse by different ages of onset
What is the most common type of JIA?
Oligoarthritis
Describe the pathophysiology of synovitis
TNF-Alpha is the pirmary mediator/
- T cells activate macrophages
- B cells are activated
- TNF is the key cytokine
- Thickening of synovial membrane, WBCs recruited and hypervascular
What is unique about systemic JIA?
Rash, ascites, enlarged axillary lymph nodes. Systemic Sx like fever and abnormal CBC
What is the Koebner phenomenon?
Scratching makes the rash worse
What are clinical features of JIA?
Growth plates closed (epiphyseal overgrowth) resulting in shortened bones
Fusion of C-spine joints
Microganthia
Uveitis
What does pauci articular arthritis in the 11-16 yo look like?
Ankylosing spondylitis
What does polyarticular disease in the 11-16 yo look like?
Rheumatoid arthritis. Will progress to this eventually
What lab values would you see in JRA?
WBC: Normal/High (systemic)
Hb: can have anemia of chronic dz
plts: normal or HIGH with acute phase rxn (rules out leukemia)
ESR: normal/high
igA: 10% are deficient
May be ANA or RF positive too. Or ACPA
Who is at highest risk for uveitis? What is so difficult with treating uveitis?
pauci and polyarticular, ANA+ children under 7. All the pts with systemic uveitis are at LOW risk. Difficult to diagnose, asymptomatic except for detection by slit lamp, and will lead to blindness. Tx with steroids
How do you treat JRA?
NSAIDS for oligoarthritis initially, then hydrochloroquinone or sulfazalazine/steroids. If not responsive, consider methotrexate
Methotrexate,leflunomide for polyarthritis/systemic cases
Biologics for systemic.
What are some biologic targets in JIA?
- Anti-CTLA-4
- Anti-IL1 and IL6
- Anti-TNF Humira
What is the cornerstone tx for polyarthritis?
Methotrexate. Note that corticosteroids, if given intra-articularly, can be disease modifying
What percent of kids will reach remission in JIA?
65% by adulthood
What is the difference between primary and secondary Raynaud’s?
Primary: excessive vasospastic response. Not more likely to get frostbite
Secondary: Usually caused by some other connective tissue disease
What are some causes of secondary Raynaud’s?
Scleroderma
SLE
Sjogren’s
Arteriolar disease
Drugs/toxins like beta blockers
Hyperproteinemia
How can you tell whether Raynauds is primary or secondary?
Secondary will show pathologic nailfold capillaries
What is chillblains? What do you need to diagnose it?
Perniosis: Venule vasodilatation, blood pools in the veins and doesn’t move. Happens in the toes. Can be primary or secondary to lupus
To tell chillblains from SLE, you need to biopsy. Will show lymphocytic infiltrate into the venules
Acrocyanosis
Shunting of blood from the periphery to the core organs. It is a normal physiologic response after birth. Hands and feet of babies turn blue
What does morphea look like? what is it?
Areas of hypopigmentation. caused by scleroderma limited to fibrosis in the dermis, subdermis, and superficial muscle. No systemic features. Only treat leasions on the face or large lesions because tight skin can cause a flexion contracture.
