Orthopedics

Juvenile Idiopathic Arthritis

Systemic Onset

  • Epidemiology: M=F, 1-6yo
  • Signs and symptoms:
    • High spiking fevers daily or twice daily
    • Evanescent salmon-colored rash
    • Lymphadenopathy, hepatosplenomegaly, pericarditis
  • Labs: RF(-), ANA(-), increased ferritin, leukocytosis, anemia, increased ESR
  • If persists: osteoporosis, short stature, brachydactyly, micrognathia
  • Differential: infection (bacterial, viral), malignancy, inflammatory bowel disease, acute rheumatic fever, systemic vasculitides (polyarteritis nodosa), collagen vascular disease (SLE)
  • Complications: Pericardial tamponade, systemic vasculitis, macrophage activation syndrome (persistent high fever, pancytopenia, active phagocytosis on bone marrow biopsy)

Pauciarticular

  • Epidemiology: F>M, 2-3yo, rare <10yo
    • Persistent – affects no more than 4 joints after 6mo
    • Extended – affects more than 4 joints after 6mo � erosive arthritis, treatment: immunosuppressant
  • Signs and symptoms:
    • �4 joints especially knee and ankle
    • Uveitis
  • Labs: ANA(+)
  • If persists: leg length discrepancy, eye problems (corneal clouding, cataracts, glaucoma, visual loss)
  • Differential: infection (get joint aspiration to rule out), Lyme, postviral, trauma, malignancy, mechanical

Polyarticular

  • RF(+)
    • Epidemiology: F>M, �8yo, (+)HLA-DR4
    • Signs and symptoms: symmetric, small joints
    • Complications: severe erosive arthritis, rheumatoid nodules, worse prognosis than RF(-)
  • RF(-)
    • Epidemiology: F>M, younger (2-5yo)
    • Signs and symptoms: asymmetric, fewer joints, ANA(+)
  • Other signs and symptoms: fatigue, malnutrition, delayed growth, anemia, osteopenia
  • Differential: Lyme, gonorrhea, viral, SLE, scleroderma, dermatomyositis, spondylarthropathies, malignancy

Enthesitis-related

  • Epidemiology: M>F
  • Signs and symptoms:
    • Inflammation of enthesis (tendon attaches to bone) � heel pain, arthritis
    • Sacroiliac joint tenderness, inflammatory spinal pain, HLA-B27, family history, uveitis, pauciarticular or polyarthritis in >8yo M
  • If persists: spondyloarthropathies (ankylosing spondylitis, reactive arthritis, IBD-associated arthritis)

Psoriatic

  • Signs and symptoms: arthritis, psoriasis, dactylitis, nail pitting (onycholysis), family history of psoriasis

Treatment

  • 1st line: NSAIDs (SE: abdominal pain, anorexia)
  • Disease-modifying anti-rheumatic drugs (DMARDs): methotrexate plus 1mg folic acid (SE: GI – oral ulcers, decreased appetite, abdominal pain), sulfasalzine, steroids (only short-term for severe manifestations)
  • Other – Etanerecpt (TNF-R antagonist), joint replacement surgery, autologous stem cell transplant (last resort)
  • PT/OT, splints, screen for uveitis

References

Goldmuntz EA and White PH. Juvenile Idiopathic Arthritis: A Review for the Pediatrician. Pediatrics in Review 2006; 27(4): e24-e32.

Espinosa et al.  Juvenile Idiopathic Arthritis. Pediatrics in Review July 2012