A woman had a large, deep ulcer at an injection site on her thigh, with a dusky violaceous border extending 2 to 5 cm from the wound edge, fever to 39.8 °C, and elevated white blood cell count and procalcitonin level; histologic examination of excised tissue showed a dense pan-dermal neutrophilic infiltrate, and multiple blood and tissue cultures were negative. What is the diagnosis and what would you do next?
Source: JAMA Online First