Group A Streptococcal Cellulitis


Group A Streptococcal Cellulitis, Group A Streptococcus Cellulitis, Erysipelas, Beta-Hemolytic Streptococcal Cellulitis, Group A Strep Cellulitis, Saint Anthony's Fire, Streptococcus Pyogenes Cellulitis, Facial Erysipelas

  • History
  • St. Anthony's Fire
  1. Refers to epidemic gangrene of the 11th century
    1. Patients presented with bright red extremities
  2. Initially attributed to fungus ingestion and Ergotism
    1. Now believed those reactions were Erysipelas
  3. Some thought skin was consumed by holy fire
    1. Only relief was via 300 AD Egyptian Monk St. Anthony
  • Epidemiology
  1. Common Ages
    1. Infants and Young children
    2. Older than age 60 years (face involvement)
  2. More common over summer months
  3. Usually occurs in isolated cases rather than epidemics
  • Pathophysiology
  • Mechanisms
  1. Most cases do not have inciting wound
  2. Post-operative infection via surgical incision
    1. Occurs 6-48 hours after surgery
  3. Trauma site
  4. Insect Bite
  5. Nasopharyngeal source
  • Causes
  • Beta-hemolytic streptococcal infection
  • Symptoms
  1. Abrupt onset with rapid course
  2. Influenza-like prodrome
    1. Fever, Chills, Malaise
    2. Headache
    3. Vomiting
  3. Red rash
    1. Associated with skin Sensation of tightness and warmth
  1. Same signs as for other forms of Cellulitis except
    1. Lesion indurated with elevated margins
    2. Irregular border that is sharply demarcated
  2. Lesions show staged progression
    1. Spreading erythema over 3-6 days
      1. Shiny, bright red erythema
      2. Painful, hot, edematous lesion
    2. Vesicles and bullae may develop and then crust
    3. Central clearing may then develop within 7-10 days
    4. Areas of involved skin may exfoliate
    5. Postinflammatory Hyperpigmentation may occur
  3. Marked lymphangitis
  4. Systemic symptoms often precede local inflammation (erythema, swelling, local warmth)
    1. Hypotension may be first sign before erythema
    2. Fever, chills and malaise may also precede skin changes by more than 24 hours
  5. Common sites of involvement
    1. Legs
      1. Congenital Lymphedema (Milroy's Disease)
      2. CABG saphenous vein harvest
        1. See Non-Group A Streptococcus Cellulitis
    2. Face (less common now than legs, see below)
  • Signs
  • Facial Erysipelas
  1. Pharyngitis may precede rash by several days
  2. Focal area on face of Paresthesia or pain
  3. Rash develops in area of sensory change
    1. Rash develops as described in signs (see above)
    2. May appear similar to SLE butterfly Malar Rash
  4. Edema may develop of eyes and cheeks
  5. Differential Diagnosis of Facial Erysipelas
    1. Staphylococcus aureusCellulitis
      1. On the face, Staphylococcal Cellulitis may be indistinguishable from streptococcal Erysipelas
    2. Buccal Cellulitis
      1. HaemophilusInfluenzae Type B, in the pre-Hib Vaccine era, caused Buccal Cellulitis (much less common now)
    3. Parvovirus B19 (Fifth Disease)
      1. Facial erythema (slapped cheek appearance) spares the chin and periorbital region
  • Differential Diagnosis
  1. See Cellulitis
  2. See Differential Diagnosis of Facial Erysipelas as above
  3. Contact Dermatitis
  4. Angioneurotic edema
  5. Herpes Zoster
  6. Erysipeloid
  7. Erythema Chronicum Migrans (Lyme Disease)
  • Labs
  1. Complete Blood Count
    1. Leukocytosis with Left Shift
  2. Antistreptolysin O titer increased
  3. Nasopharynx culture
    1. Positive for Beta-hemolytic Streptococcus
  4. Gram Stain and Culture of wound
    1. Compress wound margins for thin serous discharge
    2. Sample obtained from leading edge
    3. Painful and usually not indicated
  1. Pyoderma (Impetigo)
  2. Perianal Streptococcal Dermatitis
  3. Children with Chronic Perianal Cellulitis
    1. Intense perianal erythema
    2. Painful Defecation
    3. Blood streaked stools from Anal Fissures
  • Management
  1. See Cellulitis for antibiotic selection (including Facial Erysipelas coverage)
  2. Apply warm, moist compresses to affected area
  3. Intravenous antibiotics may be required initially
  4. Total antibiotic course: 10-14 days
  5. Facial Erysipelas appears similar to Staphylococcal Cellulitis of the face
    1. Facial Erysipelas requires MRSA coverage
    2. Vancomycin is recommended as first line antibiotic
      1. Alternatives: Daptomycin, Linezolid
  6. Extremity Erysipelas (Group A Streptococcus)
    1. See Cellulitis for antibiotic selection
    2. Oral agents: First-Line
      1. Erysipelas is sensitive to Penicillins and Cephalosporins (but often requires higher dose)
      2. Penicillin VK 500 mg orally every 6 hours for 10 days OR
      3. Amoxicillin 500 mg every 8 hours for 10 days
    3. Oral agents: Penicillin Allergic
      1. Cephalexin 500 mg orally four times daily for 10 days OR
      2. Azithromycin 500 mg on day, then 250 mg orally daily for 4 days (days 2-5)
        1. Only indicated for beta-lactam Anaphylaxis (risk of Antibiotic Resistance)
      3. Avoid Doxycycline (due to Streptococcus PyogenesAntibiotic Resistance)
      4. Avoid Trimethoprim Sulfamethoxazole (unless added to other antibiotic when MRSA is possible cause)
    4. Parenteral agents: First-Line
      1. Penicillin G 1-2 Million Units every 6 hours
    5. Parenteral agents: Penicillin Allergic
      1. Cefazolin 1 gram IV every 8 hours OR
      2. Ceftriaxone 2 grams every 24 hours
    6. Parenteral agents: Beta-Lactam Anaphylaxis
      1. Vancomycin (or Linezolid)
  • Complications
  1. Abscess (typically due to Staphylococcus aureus instead)
  2. Gangrene
  3. Superficial Thrombophlebitis
  4. Acute Glomerulonephritis
  5. Sepsis
  6. Endocarditis