Topical Amphotericin B With Wound VAC for Scalp Mucormycosis due to Apophysomyces trapeziformis

Introduction: Apophysomyces trapeziformis is a rare, angioinvasive mucormycete associated with post-traumatic infections, notably following the 2011 Joplin tornado. It causes rapid necrosis, has limited antifungal susceptibility, and carries high mortality. Management often requires aggressive debridement and prolonged antifungal therapy.


Description: A 51-year-old male presented to the trauma resuscitation unit with an invasive polymicrobial skin and soft tissue infection, a partial left upper extremity (LUE) amputation, deep scalp laceration, and a left frontotemporal subdural hematoma sustained during involvement in a rollover motor vehicle crash. He received empiric antibiotics and underwent glenohumeral disarticulation and scalp debridement, followed by intensive care unit (ICU) admission. Despite broad-spectrum antibiotics and serial debridements, he developed worsening necrosis at both sites requiring muscle and bone excision. On hospital day 8, hyphal elements were noted intraoperatively, and fungal cultures prompted initiation of voriconazole. By day 10, the organism was identified as Apophysomyces trapeziformis (mucorales). Antifungals were escalated to intravenous amphotericin B and posaconazole, later transitioned to isavuconazole due to hepatotoxicity. Ongoing scalp and LUE wound involvement led to extensive tissue loss, exposed skull bone, and failure to achieve source control despite over 25 surgical interventions. Given persistent fungal contamination and poor drug penetration to devitalized tissue, the care team initiated topical amphotericin B irrigation via wound vacuum-assisted closure (VAC) over exposed bone and necrotic soft tissue of the scalp.


Discussion: This case highlights the complexity of treating an invasive polymicrobial infection after trauma. To our knowledge, this is the first reported use of topical amphotericin B irrigation with VAC for cutaneous mucormycosis due to A. trapeziformis. This approach enabled targeted antifungal delivery to infected tissue inaccessible to systemic agents and contributed to wound stabilization and fungal clearance. Topical amphotericin irrigation may be a valuable adjunct when conventional therapy is inadequate.