Invasive mold infections following combat-related injuries

Abstract

Background: Major advances in combat casualty care have led to increased survival of patients with complex extremity trauma. Invasive fungal wound infections (IFIs) are an uncommon, but increasingly recognized, complication following trauma that require greater understanding of risk factors and clinical findings to reduce morbidity.

Methods: The patient population includes US military personnel injured during combat from June 2009 through December 2010. Case definition required wound necrosis on successive debridements with IFI evidence by histopathology and/or microbiology (Candida spp excluded). Case finding and data collected through the Trauma Infectious Disease Outcomes Study utilized trauma registry, hospital records or operative reports, and pathologist review of histopathology specimens.

Results: A total of 37 cases were identified: proven (angioinvasion, n=20), probable (nonvascular tissue invasion, n=4), and possible (positive fungal culture without histopathological evidence, n=13). In the last quarter surveyed, rates reached 3.5% of trauma admissions. Common findings include blast injury (100%) during foot patrol (92%) occurring in southern Afghanistan (94%) with lower extremity amputation (80%) and large volume blood transfusion (97.2%). Mold isolates were recovered in 83% of cases (order Mucorales, n=16; Aspergillus spp, n=16; Fusarium spp, n=9), commonly with multiple mold species among infected wounds (28%). Clinical outcomes included 3 related deaths (8.1%), frequent debridements (median, 11 cases), and amputation revisions (58%).

Conclusions: IFIs are an emerging trauma-related infection leading to significant morbidity. Early identification, using common characteristics of patient injury profile and tissue-based diagnosis, should be accompanied by aggressive surgical and antifungal therapy (liposomal amphotericin B and a broad-spectrum triazole pending mycology results) among patients with suspicious wounds.

Figure 1.

Number and percentage of patients with diagnoses of invasive fungal wound infections based on dates of admission to Landstuhl Regional Medical Center (LRMC), from June 2009 through December 2010. An average of 324 patients (range, 95–509 patients) per quarter admitted to LRMC with an average of 5 patients (range, 0–12 patients) with invasive fungal infection per quarter. Abbreviation: IFI, invasive fungal infection.

Figure 2.

Intraoperative findings of wound following explosive blast injury subsequently infected with invasive mold (A) and after successful surgical and medical therapy (B). High-level lower extremity amputation with necrotic fibrinous material documented on histopathology with aseptate mold angioinvasion (initial presentation). Wound appearance after serial debridements, hemipelvectomy, and antifungal therapy (8 days later).