Is cefuroxime (a cephalosporin) an effective treatment option for a patient with impetigo, fever, and suspected Staphylococcus aureus infection?

Is Cefuroxime Effective for Impetigo with Suspected Staphylococcus aureus?

Cefuroxime is NOT recommended as a first-line treatment for impetigo, even when Staphylococcus aureus is suspected. While cefuroxime has activity against S. aureus and is FDA-approved for skin and soft tissue infections, it is not among the guideline-recommended agents for impetigo treatment. 1, 2

Guideline-Recommended First-Line Agents

For impetigo with suspected methicillin-susceptible S. aureus (MSSA):

• Cephalexin (not cefuroxime) is the recommended first-generation cephalosporin at 25-50 mg/kg/day divided into 4 doses for 7 days 1, 2
• Dicloxacillin is an equally appropriate alternative at the same dosing schedule 1, 2

The distinction matters: cephalexin is a first-generation cephalosporin with superior anti-staphylococcal activity compared to second-generation agents like cefuroxime for this indication. 3

When MRSA is Suspected or Confirmed

If the patient has fever and systemic signs suggesting MRSA, the recommended alternatives are:

• Clindamycin at 20-30 mg/kg/day divided into 3 doses for 7 days 1, 2
• Sulfamethoxazole-trimethoprim (SMX-TMP) at 8-12 mg/kg/day divided into 2 doses for 7 days 1, 2
• Doxycycline (if patient >8 years old) at 2-4 mg/kg/day divided into 2 doses for 7 days 1, 2

Why Cefuroxime is Not Recommended

While cefuroxime has documented activity against S. aureus and is FDA-approved for skin infections 4, 5, it has several limitations for impetigo:

• Not guideline-endorsed: The 2014 IDSA guidelines specifically recommend cephalexin or dicloxacillin, not second-generation cephalosporins like cefuroxime 1
• Inferior anti-staphylococcal activity: First-generation cephalosporins have better activity against S. aureus than second-generation agents for skin infections 3
• No MRSA coverage: Cefuroxime provides no coverage for MRSA, which is increasingly common in impetigo 1, 2

Clinical Algorithm for Impetigo Treatment

Step 1: Assess severity and extent

• Limited lesions (<5 sites): Consider topical mupirocin or retapamulin for 5 days 2
• Numerous lesions or outbreak setting: Proceed to oral therapy 1, 2

Step 2: Assess for MRSA risk factors

• High local MRSA prevalence, previous MRSA infection, or failure of beta-lactam therapy: Use clindamycin or SMX-TMP 1, 2
• No MRSA risk factors: Use cephalexin or dicloxacillin 1, 2

Step 3: Duration

• All oral regimens should be given for 7 days 1, 2

Important Caveats

• Penicillin alone is inadequate: S. aureus is now the predominant pathogen in impetigo (62-100% of cases), and penicillin should only be used when cultures confirm streptococci alone 1, 6, 3
• Amoxicillin is not recommended: It lacks adequate anti-staphylococcal coverage 2
• Culture when possible: While empiric therapy is reasonable, cultures help guide therapy, especially in treatment failures 1
• Outbreak management: During outbreaks of poststreptococcal glomerulonephritis, systemic antimicrobials should be used to eliminate nephritogenic strains 1

Bottom Line

Use cephalexin (first-generation) or dicloxacillin for presumed MSSA impetigo, not cefuroxime (second-generation). 1, 2 If MRSA is suspected based on local epidemiology or clinical features (fever, systemic signs, treatment failure), switch to clindamycin or SMX-TMP. 1, 2