Invasive fungal infections associated with prior respiratory viral infections in immunocompromised hosts

Background: Increased risk of invasive pulmonary aspergillosis after influenza infection has been reported; however data are limited. Purpose: To describe Invasive fungal infections (IFI) associated with preceding respiratory viral infection at a large referral center. Methods: We reviewed all IFI cases among patients with positive influenza and/or RSV nasopharyngeal/lower respiratory tract PCR from October 2015 to December 2016. Cases of pulmonary IFI were classified as possible, probable, and definite based on EORTC-MSG definitions. Results: We identified 8 cases (4 influenza, 4 RSV); 3 with probable Aspergillosis, 1 possible Aspergillosis, 1 probable Histoplasmosis, 1 probable Mucormycosis, and 2 possible IFI (consistent clinical and imaging findings). Half of our patients were men with a mean age of 64 years (SD 8) and median Charlson Comorbidity Score of 3.5 (IQR 3-7). Most common risk factors were stem cell transplant (75%) and neutropenia (62.5%). Four patients were on antifungal prophylaxis at presentation. All patients received anti-viral therapy with oseltamivir/ribavirin and 50% received empiric antibiotics. Median duration from onset of viral infection to diagnosis of IFI was 8.5 days (IQR 2.5-14) and 75% were diagnosed during the same admission. All received antifungal therapy; 62.5% required ICU care, and 37.5% died during index hospitalization. Conclusions: Our study supports earlier observations describing IFI following respiratory viral infection in immunocompromised hosts. Secondary IFI occurred in 1.4% of our cohort and most occurred during the index admission. IFI following viral illness is associated with high mortality and early detection and therapy may improve outcomes.