Which patient scenario best indicates escalation to ED due to suspected necrotizing soft tissue infection?

• A. A patient with leg pain and soft-tissue crepitus with mild erythema
• B. A patient with simple cellulitis with mild redness
• C. A patient with a minor cut healing spontaneously
• D. A patient with localized abscess without crepitus

Answer: (A)

Gas in soft tissue, seen as crepitus, strongly suggests a necrotizing soft tissue infection that can progress rapidly and dangerously. When a patient presents with leg pain and soft-tissue crepitus, the infection may be spreading beneath the surface even if the skin looks only mildly red. This combination is a red flag because NSTIs often begin subtly but advance quickly, and crepitus indicates gas-forming organisms or extensive tissue necrosis. The correct course is immediate escalation to the emergency department for urgent surgical evaluation, broad-spectrum antibiotics, and supportive care, since prompt surgical debridement is essential for survival.

Simple cellulitis lacks gas production and typically presents with more uniform exam findings and slower progression, not the dangerous undercurrent suggested by crepitus. A minor cut healing on its own or a localized abscess without crepitus also presents far less risk of rapid necrosis or systemic deterioration, so they don’t require the same emergent ED pathway.