Skin bacterial abscess - Cellulitis DDx
Lesions evolve over days to 1-2 weeks. They are usually painful / tender, erythematous, warm, and fluctuant masses that are sometimes associated with fever. A tender subcutaneous nodule with overlying erythema but minimal fluctuance may be an early presentation. Incision and drainage is the mainstay of therapy. In an otherwise healthy, ambulatory patient, the addition of antibiotics is not indicated. Indications for the addition of antibiotics may include patients who are systemically ill, have a high burden of disease (indicated by concomitant widespread folliculitis or associated cellulitis), are immunosuppressed, or have failed incision and drainage.
Methicillin-resistant S. aureus (MRSA) first emerged as an important nosocomial pathogen in the 1960s. In more recent years, community-acquired outbreaks of MRSA (CA-MRSA) have increasingly been described among healthy individuals lacking the traditional risk factors for such infections (intravenous [IV] drug use, incarceration, participation in contact sports, etc). These strains have a propensity for causing abscesses, furunculosis, and folliculitis and have a unique antibiotic susceptibility profile from health care-associated strains of MRSA (HA-MRSA).
It has been shown that the majority of purulent skin and soft tissue infections presenting to emergency rooms across the United States are caused by CA-MRSA.
Abscesses may have an overlying cellulitis, and this may be mistaken for the primary disease process despite the presence of a purulent fluid collection. It is important to discern whether or not such a pocket of infection is present because treatment without adequate drainage does not afford a cure.
L02.91 – Cutaneous abscess, unspecified
31928004 – Abscess of skin AND/OR subcutaneous tissue
- Cellulitis or erysipelas
- In a normal host, a noninflammatory abscess is "classic" for mycobacterial infections.
- Large dermal nodules of pseudolymphoma can sometimes look like an abscess.
- Drug abuse is associated with abscesses and similar appearing foreign body granulomas.
- Majocchi granuloma
- Necrotizing fasciitis
- Sweet syndrome
- Insect bites