A 4-year-old child presents with a fever and a red and swollen foot (Figure 120-1). The patient injured her foot 3 days before with a door. On physical examination, the foot was warm, tender, red, and swollen, and the child's temperature was 39.4°C (103°F). This is classic cellulitis and the child was admitted for IV antibiotics.
Cellulitis of the foot after an injury with a door in a 4-year-old girl. (Courtesy of Richard P. Usatine, MD.)
Cellulitis is an acute infection of the skin that involves the dermis and subcutaneous tissues.
- Facial cellulitis occurs more often in adults ages 50 years or older, or in children ages 6 months to 3 years.
- Perianal cellulitis occurs more commonly in young children but can be seen in adults as well (see Chapter 111, Diaper Rash and Perianal Dermatitis).
- Often begins with a break in the skin caused by trauma, a bite, or an underlying dermatosis (e.g., tinea pedis, stasis dermatitis) (Figures 120-2, 120-3, 120-4).
- Is most often caused by group A β-hemolytic Streptococcus (GABHS) or Staphylococcus aureus. The most common etiology of cellulitis with intact skin, when it has been determined through needle aspiration and/or punch biopsy, is S. aureus, outnumbering GABHS by a ratio of nearly 2:1.1
Cellulitis and abscess of the finger after a clenched fist injury in which the patient cut his finger on the tooth of the man he assaulted. (Courtesy of Richard P. Usatine, MD.)
Cellulitis of the foot of a diabetic person in which there is possible necrosis and gangrene of the second toe, requiring hospitalization and a podiatry consult. (Courtesy of Richard P. Usatine, MD.)
Cellulitis in an older man with venous stasis dermatitis. (Courtesy of Richard P. Usatine, MD.)
There are increasing concerns about the role of community- acquired methicillin-resistant S. aureus (MRSA) in all soft-tissue infections including cellulitis.2-5
- After a cat or dog bite, cellulitis is often caused by Pasteurella multocida.
- After saltwater exposure, cellulitis can be secondary to Vibrio vulnificus in warm climates (Figure 120-5). A Vibrio vulnificus infection can be especially deadly.
Fatal Vibrio vulnificus infection with widespread cellulitis and bullae. The violaceous bullae should be a red flag for this infection and/or necrotizing fasciitis. Even though the infection was identified early, the overwhelming sepsis resulted in death. (Courtesy of Donna Nguyen, MD....