From the Guidelines
Early clinical signs of necrotizing fasciitis include severe pain disproportionate to visible skin changes, failure to respond to initial antibiotic therapy, and systemic toxicity, which can rapidly progress to septic shock, organ failure, and death if not promptly recognized and treated. According to the most recent and highest quality study 1, the diagnosis of necrotizing fasciitis is primarily based on clinical judgment, and a high index of suspicion is paramount. The study highlights that features suggesting involvement of deeper tissues include:
- Severe pain that seems disproportional to the clinical findings
- Failure to respond to initial antibiotic therapy
- The hard, wooden feel of the subcutaneous tissue, extending beyond the area of apparent skin involvement
- Systemic toxicity, often with altered mental status
- Edema or tenderness extending beyond the cutaneous erythema
- Crepitus, indicating gas in the tissues
- Bullous lesions
- Skin necrosis or ecchymoses
The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score can be useful in identifying patients with necrotizing fasciitis, with a score of 8 or higher indicating a 75% risk of a necrotizing soft tissue infection 1. However, the study notes that the LRINEC score should not be used to rule out necrotizing fasciitis due to its poor sensitivity. Instead, early warning system scores, such as the quick SOFA (qSOFA) score, can be used to identify patients with suspected infection who are likely to have a poor outcome 1.
The "finger test" can be diagnostic, where a small incision is made under local anesthesia, and lack of resistance to blunt finger dissection along the fascial plane and presence of dishwater-gray fluid suggest necrotizing fasciitis 1. Immediate surgical consultation and aggressive treatment with broad-spectrum antibiotics and surgical debridement are essential upon suspicion of necrotizing fasciitis to reduce morbidity, mortality, and improve quality of life.
From the Research
Early Clinical Signs of Necrotizing Fasciitis
The early clinical signs of necrotizing fasciitis can be subtle and are often missed or delayed, leading to high mortality rates 2, 3. Some common signs and symptoms include:
- Pain and swelling of the affected area, which can be severe and disproportionate to the appearance of the wound 4, 5
- Erythema and warmth of the skin, which can progress to necrosis and gangrene 2, 6
- Fever and chills, which can indicate a systemic infection 4, 3
- Crepitus or crunching sensation under the skin, which can indicate gas production by the infecting organisms 2, 6
- Bullae or blisters, which can rupture and leave open sores 4, 5
Diagnostic Challenges
Diagnosing necrotizing fasciitis can be challenging due to the lack of specific clinical features in the initial stage of the disease 2. It is often underestimated or confused with cellulitis or abscess 2, 3. A high index of clinical suspicion is essential for early diagnosis, and diagnostic tools such as tissue biopsy and frozen section evaluation can be useful in establishing an accurate diagnosis 6.
Importance of Early Recognition and Treatment
Early recognition and treatment of necrotizing fasciitis are critical to preventing morbidity and mortality 2, 3, 5, 6. Immediate surgical debridement of necrotic tissue, broad-spectrum antibiotics, and aggressive nutritional support are essential components of treatment 2, 4, 6. Delayed treatment can lead to poor outcomes, including amputation and death 3, 5.