What is the recommended antibiotic for burn infections?

Recommended Antibiotic for Burn Infections

For burn wound infections, antibiotic selection should be culture-guided when possible, targeting the polymicrobial flora that typically includes both Gram-positive and Gram-negative organisms, with broad-spectrum beta-lactams like cefepime or piperacillin-tazobactam administered at high doses via continuous infusion being the preferred empiric systemic therapy when infection is documented. 1

Key Principle: Prophylaxis vs. Treatment

Universal antibiotic prophylaxis is NOT recommended for burn wounds. 1 The evidence shows:

• Systemic antibiotic prophylaxis administered in the first 4-14 days significantly reduced mortality by nearly half, but limited perioperative prophylaxis reduced wound infections without affecting mortality 1
• Topical antibiotic prophylaxis (including silver sulfadiazine) applied to burn wounds had no beneficial effects and was associated with increased burn wound infections and longer hospital stays 1
• The Surviving Sepsis Campaign explicitly recommends against sustained systemic antimicrobial prophylaxis in patients with burn injury in the absence of infection 1

When to Initiate Antibiotics

Antibiotics should be reserved for patients with:

• Documented burn wound infection (not just colonization) 1
• Systemic signs of infection (fever, hemodynamic instability, sepsis) 1
• Spreading cellulitis beyond the burn wound 1
• Severe comorbidities or compromised immune status 1

Microbiology of Burn Wound Infections

Burn wound infections are typically polymicrobial: 1

• Early colonization (immediate): Gram-positive bacteria from endogenous skin flora (S. aureus, including MRSA)
• Later colonization (within 1 week): Gram-negative bacteria predominate (Pseudomonas aeruginosa, E. coli, Klebsiella, Enterobacter)
• Anaerobes may also be present in deeper infections

Recommended Antibiotic Regimens

For Documented Burn Wound Infections:

Empiric broad-spectrum coverage targeting both Gram-positive and Gram-negative organisms is required: 1

First-line options:

• Cefepime 2g every 8-12 hours (or higher doses with continuous infusion) 2, 3, 4, 5, 6
• Piperacillin-tazobactam (high doses with continuous infusion preferred) 5
• Meropenem or imipenem-cilastatin (for severe infections or resistant organisms) 5

Critical Dosing Considerations in Burn Patients:

Burn patients have altered pharmacokinetics requiring dose adjustments: 1, 4, 5

• Increased clearance of antibiotics due to hyperdynamic circulation 4
• Increased volume of distribution correlating with percent third-degree burn 4
• High doses and continuous infusion are needed to achieve adequate PK/PD targets 5
• Therapeutic drug monitoring should guide dosing when available 1, 5

For cefepime specifically in burn patients:

• Standard dosing of 1g q8h, 2g q8h, or 2g q12h may be adequate for organisms with lower MICs 4
• However, continuous infusion at higher doses is increasingly recommended to maintain serum concentrations above MIC for >60-70% of the dosing interval 2, 5

MRSA Coverage:

Add MRSA-directed therapy based on: 1

• Local epidemiology (>20% MRSA prevalence) 1
• Previous MRSA colonization or infection
• Failure to respond to initial therapy

MRSA treatment options:

• Vancomycin 1
• Linezolid 1
• Daptomycin 1

Topical Therapy:

Silver sulfadiazine cream 1% is FDA-approved as an adjunct for prevention and treatment of wound sepsis in second and third-degree burns 7:

• Apply once to twice daily to thickness of 1/16 inch 7
• However, recent evidence shows it may increase infection rates and hospital stay compared to modern dressings 1
• Continue until satisfactory healing or burn site ready for grafting 7

Essential Non-Antibiotic Management

Surgical source control is paramount and more important than antibiotics: 1

• Early excision of eschar substantially decreases invasive burn wound infection 1
• Debridement of necrotic tissue is necessary to remove pathogens 1
• Mechanical reduction of pathogen burden through wound care 1

Culture-Guided Therapy

Bacterial cultures should guide antibiotic selection: 1

• Obtain cultures before initiating antibiotics when possible
• Adjust therapy based on susceptibility results
• This is especially important given increasing bacterial drug resistance 1

Common Pitfalls to Avoid

• Do not use prolonged prophylactic antibiotics without documented infection 1
• Do not rely solely on topical silver sulfadiazine given evidence of harm 1
• Do not use standard dosing regimens without considering altered pharmacokinetics in burn patients 1, 4, 5
• Do not neglect surgical debridement in favor of antibiotics alone 1