LAUSR

PG: pyoderma gangrenosum INTRODUCTION Pyoderma gangrenosum (PG) is an inflammatory condition that causes neutrophilic infiltration of the skin and characteristic skin ulceration. More than half of patients develop PG in association with an underlying systemic disease. Its pathophysiology is complicated and not fully understood. PG can affect any part of the body, but it commonly affects the legs. The diagnosis of PG can be challenging and is often one of exclusion. PG exhibits pathergy, which is the development or worsening of a lesion at the site of trauma, and the presence of pathergy can help support the diagnosis of PG. PG can closely resemble other entities included in the differential diagnosis, such as serious skin infections, which can be found with postoperative wounds or cases of necrotizing fasciitis. Because these conditions are often managed with surgical debridement, establishing the correct diagnosis is critical. Avoidance of surgical debridement of PG is typically recommended to limit pathergy. We present a case in which worsening of a patient’s PG following surgical debridement led to the exposure of her tibialis anterior tendon, which became desiccated and superficially necrotic with subsequent functional impairment.