On x ray of affected area, necrotizing fasciitis is characterized by subcutaneous gas or soft tissue swelling (specific x-ray finding) and increased soft tissue thickness and opacity. Chest x-ray findings associated with necrotizing fasciitis include early changes of fluid overload and adult (acute) respiratory distress syndrome (ARDS).

• On X-ray, necrotizing fasciitis is characterized by:^[1]

• Subcutaneous gas or soft tissue swelling (specific x-ray finding)
• Increased soft tissue thickness and opacity

• Plain x-ray is a poor screening study for necrotizing fasciitis because:

• Subcutaneous emphysema is an insensitive finding and is present in a minority of patients
• In the early stages the findings are similar to cellulitis

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  X ray of hip showing subcutaneous gas – Case courtesy of Dr Wael Nemattalla, Radiopaedia.org, rID: 8674
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  X ray (Necrotizing fasciitis of diabetic foot) – Case courtesy of Dr Wael Nemattalla, Radiopaedia.org, rID: 8674

• Chest x ray findings are associated with necrotizing fasciitis include:

• Early changes of fluid overload
• Changes of adult (acute) respiratory distress syndrome (ARDS).