1709. Epidemiology of Invasive Fungal Infection (IFI) after Severe Influenza Requiring Intensive Care Unit (ICU) Admission: 10-Year Experience at a Tertiary Care Center in the United States

BACKGROUND: Despite increasing recognition of aspergillosis complicating severe influenza and its associated high fatality in Europe, incidence and features of the disease in the United States are unknown. METHODS: We reviewed all influenza cases requiring ICU admission from 2009 to 2019 at our center. RESULTS: 262 patients with influenza required ICU admission. 4% (10) developed IFI at median 2d after influenza diagnosis. 80% (8/10) of patients with IFI were infected with influenza A vs. 88% (221/252) without IFI. 20% were on steroids at the time of IFI diagnosis. 70% of IFI required mechanical ventilation. Types of IFI were pneumonia (70%, 6 Aspergillus and 1 Wangiella), endobronchial IFI (20%, 1 each with Aspergillus and Lictheimia), and Coccidioides fungemia (10%). 4% (10) of patients were fungal colonized, but did not have IFI (5 A. fumigatus, 1 A. terreus, 4 Penicillium). CT findings of IFI included nodules (4), cavitation (3), and ground-glass opacities (2). Serum galactomannan (GM) was positive in 3 (43%). Median time to antifungal therapy (AF) was 2 days. Triazoles were prescribed to all 7 patients with aspergillosis. Posaconazole and amphotericin B were AF for patients with Wangiellaand Lichteimia, respectively. Patients with C. immitis fungemia died before AF. Median duration of AF was 60 days among survivors. Patients with IFI required acute hemodialysis more frequently than colonized patients (60% vs. 0%, P = 0.01). 30-day mortality was 60% (6/10) and 20% 92/10) in patients with IFI and colonization, respectively (P = 0.2). Patients with IFI had significantly higher in-hospital and 60-day mortality than those without IFI (Fig 1, P = 0.009). CONCLUSION: Our rate of post-influenza IFI (4%) was lower than reported in Europe (~15%), which might stem from a lack of systematic BAL GM testing at our center, over-reliance on GM to make diagnoses in Europe, and/or differences in pt populations and clinical practices in treating severe influenza. IFI and fungal colonization rates were similar at our center, highlighting the importance of using well-defined criteria to define disease. Given the high mortality of post-influenza IFI, priority should be given to defining risk factors that might identify patients for targeted AF prophylaxis. In using AF, it is important to recognize that Aspergillus is not the only cause of IFI. [Image: see text] DISCLOSURES: All authors: No reported disclosures.