U.S. Combat-related Invasive Fungal Wound Infection (IFI) Epidemiology and Wound Microbiology: Afghanistan Theater 2009-2014

Abstract Background Culturing combat-related wounds often yields both fungi and bacteria. It is difficult to differentiate fungal contamination from infection, and objective criteria that identify patients at risk for IFI are needed. This study was designed to characterize IFI among US combat casualties in the Afghanistan Theater. Methods This retrospective study includes subjects with any labortory evidence of fungi (either histopathology or cultures). Wounds with ongoing necrosis and labortory evidence of infection were classified as IFI). Wounds with labortory evidence of fungal infection, but without ongoing necrosis were classified as either highly suspicious wounds based on objective clinical criteria (i.e., presence of systemic and local signs of infection and use of antifungals for ≥10 days) or non-IFI wounds if they failed to meet clinical criteria. Results Of 1932 subjects, 246 (12.7%) had labortory evidence of fungal infection. There were a total of 143 IFI wounds (n = 94), 157 non-IFI wounds (n = 96), and 113 high suspicion wounds (n = 56). IFI subjects had significantly higher injury severity scores (ISS median: 39.5 vs. 33), Sequential Organ Failure Assessment (SOFA) scores (7 vs. 2) and were more likely to require mechanical ventilation (66 vs. 28%). IFI patients also had higher ISS (93 vs. 84% with ISS >25) and SOFA scores (7 vs. 4) compared with the subjects with high suspicion wounds. IFI wounds often grew molds belonging to the order Mucorales compared with high suspicion (19 vs. 10%, P = 0.04) and non-IFI wounds (19 vs. 7%, P = 0.02). About half of the IF wounds grew fungi of the order Mucorales either isolated alone or in conjunction with other fungi, in comparison, 25% of the high suspicion wounds and 11% of the non-IFI wounds grew fungi of the order Mucorales. Three groups of fungi belonging to the order Mucorales, genus Aspergillus and Fusarium accounted for 83% of the IFI wounds and 74% of the high suspicion wounds. Conclusion Labortory evidence of fungal infection is common among combat casualties. Clinical characteristics and wound microbiology allows us to group subjects into groups at low and high risk of IFI. Fungi of the order Mucorales, genus Aspergillus and Fusarium should not be considered contaminants. The presence of these fungi should obligate close clinical follow-up and debridement as needed. Disclosures All authors: No reported disclosures.