From the Guidelines
Necrotizing fasciitis can be caused by a monomicrobial infection, such as Group A Streptococcus (GAS), and does not require a polymicrobial infection for diagnosis. In fact, Group A Strep is one of the most common causes of monomicrobial necrotizing fasciitis, often referred to as Type II necrotizing fasciitis [ 1 ]. This form of the disease typically progresses rapidly and can be highly aggressive.
Key Considerations
- Treatment for GAS necrotizing fasciitis includes immediate surgical debridement of all infected tissue, along with high-dose intravenous antibiotics [ 1 ].
- The recommended antibiotic regimen typically includes penicillin G plus clindamycin to combat the toxin production by GAS [ 1 ].
- In penicillin-allergic patients, vancomycin, linezolid, or daptomycin may be used [ 1 ].
- Treatment duration is typically 2-3 weeks, depending on clinical response [ 1 ].
- Intravenous immunoglobulin (IVIG) may also be considered in cases of streptococcal toxic shock syndrome [ 1 ].
Rationale
The reason clindamycin is added to penicillin is that it inhibits protein synthesis, reducing toxin production even when bacteria are in a stationary growth phase, while penicillin is most effective against rapidly dividing bacteria [ 1 ].
Clinical Implications
- Prompt surgical consultation is recommended for patients with aggressive infections associated with signs of systemic toxicity or suspicion of necrotizing fasciitis [ 1 ].
- Empiric antibiotic treatment should be broad, as the etiology can be polymicrobial or monomicrobial [ 1 ].
From the Research
Causes of Necrotizing Fasciitis
- Necrotizing fasciitis can be caused by a monomicrobial infection, such as Group A Streptococcus (GAS) 2, 3.
- However, a polymicrobial infection with a variety of Gram-positive, Gram-negative, aerobic, and anaerobic bacteria is more common 3, 4.
- The infection can be caused by toxin-producing virulent bacteria, and patients can become colonized with their own aerobic and anaerobic microflora from the gastrointestinal and/or urogenital tracts 5.
Characteristics of Necrotizing Fasciitis
- Necrotizing fasciitis is a rare and often fatal soft-tissue infection involving the superficial fascial layers of the extremities, abdomen, or perineum 3.
- It is characterized by rapidly spreading inflammation and subsequent necrosis of the muscle fascia and of the surrounding tissues 2.
- The infection can start with trauma, but the inciting event may be as seemingly innocuous as a simple contusion, minor burn, or insect bite 3.
Diagnosis and Treatment
- Early diagnosis and aggressive surgical management are crucial for the management of necrotizing fasciitis 5, 6, 4.
- Prompt diagnosis is imperative because necrotizing infections typically spread rapidly and can result in multiple-organ failure, adult respiratory distress syndrome, and death 3.
- Surgical debridement is the mainstay of treatment, and repetitive surgical debridement may be necessary 5, 6, 4.
- Broad-spectrum antibiotic coverage is also critical to reduce the morbidity and mortality of these rapidly progressing infections 6, 3.