Acute rheumatic fever

Background

• Primarily affects school age children 2-6wk after strep pharyngitis
• Connective tissue of heart, joints, CNS, subq tissues are targeted by immune reaction

Diagnosis

Modified Jones Criteria (1992) for Acute Rheumatic Fever

REQUIRE: 2 major or 1 major and 2 minor criteria and evidence of previous GAS pharyngitis.

1. Major diagnostic criteria
   1. Carditis
      1. New or changing murmur, cardiomegaly, CHF, pericarditis
   2. Migratory polyarthritis
   3. Chorea
   4. Subcutaneous nodules
   5. Erythema marginatum
2. Minor diagnostic criteria
   1. Fever
   2. Arthralgia
   3. History of previous attack of rheumatic fever
   4. Prolonged PR interval
   5. Elevated ESR, CRP
3. Evidence of preceding streptococcal infection
   1. Increased ASO or other strep ab
   2. Positive throat culture for Group A strep
   3. Positive rapid GAS
   4. Recent scarlet fever

Symptoms

• Polyarthritis
  • Most common symptom (75%)
  • Migratory, fleeting polyarticular arthritis primarily affecting large joints
• Carditis (33%)
  • Most serious complication and second most common
    • New murmur, pericardial rub, CHF
• Chorea (10%)
  • May appear months following strep infection, may be sole manifestation of RF
• Erythema marginatum
  • Persists only for several days
  • Usually coexists with presence of carditis in some form
  • Nonpruritic, located on trunk and proximal limbs, never on face
• Nodules
  • Located on extensor surfaces of wrists, elbows, knees

Differential Diagnosis

1. JIA
2. Septic Arthritis
3. Kawasaki Disease
4. Viral or other forms of cardiomyopathy
5. Leukemia
6. Vasculitis (HSP, drug reaction)
7. Hip Pain (Peds)

Pediatric limp

Hip Related

• Acute rheumatic fever
• Developmental dysplasia of hip
• Femur fracture
• Juvenile idiopathic arthritis
• Legg-Calve-Perthes disease
• Septic arthritis of the hip (peds)
  • Lyme disease arthritis
• Slipped capital femoral epiphysis
• Transient (toxic) synovitis
• Osteosarcoma

Other Causes of Limping

• Developmental dysplasia
• Fracture
  • Toddler's fracture
  • Tillaux fracture, adolescent
• Neoplasm:
  • Leukemia
  • Ewings
  • Osteogenic sarcoma
  • Metastatic neuroblastoma
• Osteomyelitis
• Myositis
• Other:
  • Appendicitis
  • Meningitis
  • Epidural abscess (spinal)

Work-Up

1. CBC
2. ECG
3. CXR
4. ESR, CRP

Treatment

• Penicillin
  • Indicated for all pts w/ rheumatic fever even if cx for strep is negative
  • 600K units IM if <27 kg
  • 1.2 million units IM if >27 kg
  • Penicillin V PO x10d
  • Prophylaxis
    • 5yr if no cardiac involvement, lifetime if cardiac involvement
    • Pen G IM q month or oral penicillin daily
  • Erythromycin x10d if pen allergic
• Arthritis
  • High-dose aspirin therapy (75-100 mg/kg/d)
• Carditis
  • Prednisone 1-2mg/kg/d
• Chorea
  • Haloperidol 0.01-0.03 mg/kg/d in four divided doses

Disposition

• Admit for confirmation of diagnosis

Source

Tintinalli