Skin & Soft Tissue Infections

Skin & Soft Tissue Infections

  • Cellulitis of dental origin
  • Diabetic foot infections
  • Severely immunocompromised patients (e.g. neutropenia, immunosuppressive therapy)
  • Surgical site infections
  • Recent history of fresh/salt water exposure
  • Recent hot tub use
  • Cellulitis associated with fish and seafood processing

Treatment Criteria and Considerations

  • The diagnosis of cellulitis is largely clinical, and the initial treatment is usually empirical.
  • Misdiagnosis is not uncommon, so the clinician should be alert to the possibility of cellulitis “mimics”, such as: venous stasis dermatitis, DVT/thrombophlebitis, hematomas, and gout.
  • Cellulitis of the extremities is almost always unilateral.
    • “Bilateral cellulitis” is extremely unlikely; first consider an alternate non-infectious diagnosis
  • Evaluate all patients for predisposing features (e.g. tinea pedis, dermatoses, lymphedema, venous stasis, wounds) as the source of cellulitis, especially in the setting of recurrent cellulitis.
    • If possible, treat predisposing factors to prevent recurrent cellulitis.
    • May consider MRSA decolonization in patients with recurrent MRSA infections.
  • Non-pharmacologic interventions (such as elevation and compression of the affected limb, if appropriate) are adjunctive, but essential, components of cellulitis management:
    • Affected upper extremities should be elevated higher than the shoulder.
    • Affected lower extremities should be elevated higher than the hip joint.
  • Marking the outline of the erythema and/or daily photographs may assist in the assessment.
  • Assessment of clinical response in the first 48 hours should be limited to improvement of: pain, fever, and the patient’s overall condition
    • During the first 48 hours, a mild progression of erythema is expected and “acceptable”.
  • Review and adjust therapy as needed if microbiology results become available.
  • There is no evidence to support that IV therapy is superior to PO therapy in the management of uncomplicated cellulitis*.
  • There is no evidence to support a minimum duration of IV therapy for the management of uncomplicated cellulitis*.
  • Patients meeting the following suggested criteria can generally have their therapy converted from IV to PO:
    • The patient is afebrile for at least 24 hours.
    • Clinical improvement (such as: overall clinical improvement, decreased pain).
    • There are no complicating factors (e.g. deeper tissue involvement, undrained abscess, insufficient perfusion to the affected area).
    • The patient can tolerate oral medications that will achieve adequate tissue levels.

*Uncomplicated cellulitis: cellulitis WITHOUT periorbital involvement, severe sepsis, extensive bullous skin changes, undrained abscesses, deep tissue involvement, necrotizing fasciitis, or infected prosthetic material.

  • In patients with uncomplicated cellulitis who show improvement after 72 hours of therapy, a duration of therapy of 5 days is just as effective as 10 days.
  • In cellulitis, a relatively small number of bacteria cause a disproportionately large amount of inflammation.
  • Greater than 5 days of therapy is rarely required if the patient responds within the first 72 hours of therapy.
  • Follow-up is essential to re-assure patients (and prescribers) that any residual redness is only due to inflammation.

*Uncomplicated cellulitis: cellulitis WITHOUT periorbital involvement, severe sepsis, extensive bullous skin changes, undrained abscesses, deep tissue involvement, necrotizing fasciitis, or infected prosthetic material.

  • MRSA is most often associated with PURULENT skin and soft tissue infections. It has been common practice to prescribe anti-MRSA therapy for all cases of mild to moderate cellulitis in patients with a history of MRSA.
  • However, only mild to moderate PURULENT cellulitis requires empiric anti-MRSA therapy, even in the setting of prior MRSA infection.
  • Empiric coverage of MRSA is NOT required in mild to moderate NON-purulent cellulitis.
  • Risk Factors for MRSA include:
    • History of MRSA infection or colonization
    • Household contact with a MRSA colonized individual
    • IV drug use
    • Homelessness
    • Incarcerated persons
    • Recent travel to or residing in an MRSA endemic region or community

Additional Information

Guideline content derived from:

  • NB Provincial Health Authorities Anti-Infective Stewardship Committee. Treatment of Skin & Soft Tissue Infections. 02-2021
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