Combat-Related Invasive Fungal Wound Infections

Abstract

Combat-related invasive fungal (mold) wound infections (IFIs) have emerged as an important and morbid complication following explosive blast injuries among military personnel. Similar to trauma-associated IFI cases among civilian populations, as in agricultural accidents and natural disasters, these infections occur in the setting of penetrating wounds contaminated by environmental debris. Specific risk factors for combat-related IFI include dismounted (patrolling on foot) blast injuries occurring mostly in southern Afghanistan, resulting in above knee amputations requiring resuscitation with large-volume blood transfusions. Diagnosis of IFI is based upon early identification of a recurrently necrotic wound following serial debridement and tissue-based histopathology examination with special stains to detect invasive disease. Fungal culture of affected tissue also provides supportive information. Aggressive surgical debridement of affected tissue is the primary therapy. Empiric antifungal therapy should be considered when there is a strong suspicion for IFI. Both liposomal amphotericin B and voriconazole should be considered initially for treatment since many of the cases involve not only Mucorales species but also Aspergillus or Fusarium spp., with narrowing of regimen based upon clinical mycology findings.

Keywords: Combat-related trauma; Invasive fungal infections; Invasive mold infections; Invasive mucormycosis; Wound infections.

Fig. 1

Progression of an invasive fungal wound infection following blast injury. a Wound immediately following blast injury, demonstrating severity of contamination. b Following surgical debridement and high-level lower extremity amputation with necrotic fibrinous material documented on histopathology with aseptate mold angioinvasion (initial presentation). c Wound appearance after serial debridements, hemipelvectomy, and antifungal therapy (8 days after photo was taken of wound in b). Wounds in b and c are from the same patient. The photos were provided by CAPT (sel) Carlos Rodriguez (Trauma Surgery) and CDR Mark Fleming (Orthopedics, National Naval Medical Center). A portion of this figure has been reprinted from Warkentien et al. [56••] by permission of Oxford University Press

Fig. 2

Wound tissue histopathology. a Hematoxylin and eosin staining of necrotic tissue showing mold with broad aseptate hyphae at low power (×200). b Hematoxylin and eosin staining of necrotic tissue showing mold with broad aseptate hyphae at high power (×400). c Gomori methenamine silver staining (×100) showing angioinvasive mold with septate hyphae. The photos were provided by MAJ Justin Wells (Pathology, Walter Reed National Military Medical Center)