What is the most common source of infection in burn patients?

The Burn Wound is the Most Common Source of Infection in Burn Patients

The burn wound is the most common source of infection in burn patients. 1, 2, 3

Pathophysiology and Risk Factors

Burn injuries create a perfect environment for infection development due to:

• Loss of the protective skin barrier
• Presence of devitalized tissue (eschar) that serves as an excellent medium for bacterial growth
• Profound immunosuppression following severe burns
• Hypermetabolic and hyper-inflammatory state

The risk of infection increases with:

• Greater total body surface area (TBSA) burned (significantly higher mortality when >40%) 2
• Deeper burn injuries
• Presence of inhalation injury
• Presence of indwelling devices 2

Microbial Colonization Pattern

The burn wound undergoes a predictable pattern of colonization:

• Initial colonization with gram-positive organisms (primarily Staphylococcus species)
• Later replacement by gram-negative organisms (commonly Pseudomonas species) 2, 3

This shift in microbial flora is important to recognize when considering empiric antimicrobial therapy.

Diagnostic Approach

Accurate diagnosis of burn wound infection requires:

• Regular wound surveillance with quantitative cultures
• Tissue biopsy from the advancing margin of the wound (not surface swabs alone)
• Histopathological examination to assess microbial invasion 1

It's important to note that surface swab cultures only reflect surface colonization rather than true tissue invasion. Quantitative bacterial cultures of tissue biopsies provide more accurate assessment of infection status 1.

Prevention and Management

Key strategies to prevent and manage burn wound infections include:

1. Early excision of burn eschar - Critical for removing the source of potential infection 2
2. Prompt wound closure - Reduces the risk of invasive infection
3. Topical antimicrobial therapy - Applied directly to the wound
4. Systemic antibiotics - When indicated by signs of invasive infection
5. Strict infection control measures - To prevent cross-contamination

Other Sources of Infection in Burn Patients

While the burn wound is the primary source, other important sources of infection include:

• Pneumonia (second most common infection in modern burn care) 4
• Catheter-related bloodstream infections
• Urinary tract infections
• Surgical site infections

Clinical Implications

The recognition that burn wounds are the primary source of infection has important clinical implications:

• Early and aggressive wound management is essential
• Regular monitoring of the burn wound for signs of infection
• Appropriate selection of topical antimicrobials based on wound cultures
• Prompt surgical intervention when invasive infection is suspected

By focusing infection control efforts on the burn wound, clinicians can significantly reduce the risk of systemic infection and sepsis, which remains the leading cause of death in burn patients despite advances in care.