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  • • Common invasive nonsuppurative infection of connective tissue

    • Diffuse inflammation in the absence of findings indicating necrotizing infection

    • Usually appears on an extremity

    • A surgical wound, puncture, skin ulcer, or patch of dermatitis is usually identifiable as a portal of entry

    • Most often caused by group A streptococci and S aureus


  • • Often occurs in susceptible patients, eg, alcoholics with postphlebitic leg ulcers

    • Cellulitis due to gram-negative bacterial infection (Proteus mirabilis and Klebsiella) may develop in immunocompromised patients

Symptoms and Signs

  • • Brawny red or reddish-brown area of edematous skin

    • Advances rapidly from its starting point, and the advancing edge may be vague or sharply defined

    • Moderate or high fever is almost always present

    • Warm, erythematous, edematous area

    • Painful spreading inflammation of the skin

    • Nonelevatated, poorly defined, advancing margins

    • Lymphangitis arising from cellulitis produces red, warm, tender streaks 3-4 mm wide leading from the infection along lymphatic vessels

Laboratory Findings

  • • Most cases are caused by streptococci or staphylococci, but other bacteria have been involved

    • Bacteria are difficult to obtain for culture

    • Blood cultures positive only 2% of the time

    • Needle aspiration yields positive cultures only 20-40% of the time

    • Leukocytosis

Imaging Findings

  • • Radiographs may reveal nonspecific edematous soft tissue

  • • Thrombophlebitis

    • Contact dermatitis

    • Chemical inflammation due to drug injection

    • Hemorrhagic bullae and skin necrosis suggests necrotizing fasciitis

Rule Out

  • • Must be distinguished from necrotizing infection

  • • Complete history and physical exam

    • History of open wound, break in skin, puncture

    • Swab may be taken from lesion for culture

When to Admit

  • • High fever, spreading inflammation, failure of oral antibiotic regimen

    • Cellulitis of the face, hand, orbits, periorbital region

  • • Therapy should consist of rest, elevation, warm packs, and a PO or IV antibiotic

    • Warm packs may be used to elevate subcutaneous tissue temperature

    • Treatment is predominantly nonoperative



  • • If there is progression to necrotizing infection

    • Abscesses require drainage


  • • Penicillins or first-generation cephalosporins given IV

Treatment Monitoring

  • • If a clear response has not occurred in 12-24 hours, an abscess should be suspected or consider the possibility that the causative agent is a gram-negative rod or resistant organism

    • Patient must be examined once daily or more often to detect a hidden abscess masquerading within or under an area of cellulitis


  • • Sepsis


Corwin ...

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