Inpatient Antibiotic Regimens for Cellulitis Management
For hospitalized patients with cellulitis requiring inpatient management, vancomycin plus either piperacillin-tazobactam or imipenem/meropenem is recommended as the first-line empiric regimen for severe infections. 1
Classification and Initial Assessment
Cellulitis requiring hospitalization can be categorized based on severity 1:
- Moderate nonpurulent cellulitis: Systemic signs of infection without hemodynamic instability
- Severe nonpurulent cellulitis: Associated with SIRS, altered mental status, or hemodynamic instability
Hospitalization is recommended for patients with 1:
- Concern for deeper or necrotizing infection
- Poor adherence to therapy
- Severe immunocompromise
- Failure of outpatient treatment
First-Line Antibiotic Regimens for Inpatient Management
For Complicated Skin and Soft Tissue Infections (cSSTI)
- Empiric therapy for MRSA should be considered pending culture data 1
- Options include:
For Severe Infections
- Vancomycin plus either piperacillin-tazobactam or imipenem/meropenem is recommended as a reasonable empiric regimen (strong, moderate) 1
For Nonpurulent Cellulitis in Hospitalized Patients
- A β-lactam antibiotic (e.g., cefazolin) may be considered initially 1
- Modify to MRSA-active therapy if there is no clinical response (A-II) 1
Special Considerations
For Streptococcal Skin Infections
- Penicillin 2-4 million units every 4-6 hours IV 1
- Alternatives: clindamycin, vancomycin, linezolid, daptomycin, or telavancin 1
For Recurrent Abscesses
- Nafcillin 1-2 g every 4-6 hours IV 1
- After obtaining cultures, treat with a 5-10 day course of an antibiotic active against the pathogen 1
For Pediatric Patients
- In hospitalized children with cSSTI, vancomycin is recommended (A-II) 1
- If the patient is stable without ongoing bacteremia, empirical therapy with clindamycin 10-13 mg/kg/dose IV every 6-8 hours is an option if local clindamycin resistance rate is low (<10%) 1
- Linezolid is an alternative: 600 mg PO/IV twice daily for children >12 years and 10 mg/kg/dose PO/IV every 8 hours for children <12 years (A-II) 1
Duration of Therapy
- 7-14 days of therapy is recommended for complicated skin and soft tissue infections 1
- Treatment should be individualized based on clinical response 1
- Recent evidence suggests that 5 days of therapy may be sufficient for uncomplicated cellulitis if clinical improvement has occurred 3, 1
- Treatment should be extended if the infection has not improved within the initial treatment period (strong, high) 1
Diagnostic Considerations
- Blood cultures are recommended in hospitalized patients with cellulitis (strong, moderate) 1
- Cultures and microscopic examination of cutaneous aspirates, biopsies, or swabs should be considered in patients with 1:
- Malignancy on chemotherapy
- Neutropenia
- Severe cell-mediated immunodeficiency
- Immersion injuries
- Animal bites
Adjunctive Measures
- Elevation of the affected area is recommended (strong, moderate) 1
- Treatment of predisposing factors such as edema or underlying cutaneous disorders 1
- For lower-extremity cellulitis, examine interdigital toe spaces and treat fissuring, scaling, or maceration 1
- Systemic corticosteroids (e.g., prednisone 40 mg daily for 7 days) could be considered in nondiabetic adult patients (weak, moderate) 1
Common Pitfalls and Caveats
MRSA is an unusual cause of typical cellulitis, but coverage should be considered in cellulitis associated with 1:
- Penetrating trauma, especially from illicit drug use
- Purulent drainage
- Concurrent evidence of MRSA infection elsewhere
- Systemic toxicity
The use of rifampin as a single agent or as adjunctive therapy for the treatment of SSTI is not recommended (A-III) 1
Outpatient parenteral antibiotic therapy may be considered for patients who require IV antibiotics but are otherwise stable, potentially reducing hospitalization costs 4