Invasive Fungal Infections After Viral Pneumonia: Covid-19–associated Mucormycosis and Corticosteroid Exposure

Invasive fungal infections (IFIs) have recently come to the forefront as a complication of viral pneumonia, especially in the context of the COVID-19 pandemic.1,2,8 Immune modulation by viral infections, epithelial injury, and metabolic derangements provide a fertile ground for the opportunistic pathogens Mucorales, Aspergillus, and Candida.9,23,24 COVID-19-associated mucormycosis (CAM) has recently received international attention for its aggressive presentation and high mortality rates, particularly in diabetic patients and those receiving systemic corticosteroids.1-3 The combined effect of viral infection, immune modulation, and immunosuppressive therapy has been an important factor in the increasing incidence of post-viral fungal infections globally.2,4 Corticosteroids, while useful in the management of hyperinflammation in severe COVID-19, increase the risk of fungal infections due to their immunosuppressive effects and contributions to hyperglycemia.19,20,21 The clinical presentation of post-viral IFIs can vary from rhino-orbital disease to systemic disease, making early diagnosis and management challenging.4,13 This review aims to focus on the epidemiology, pathophysiology, clinical presentation, diagnostic difficulties, and management of IFIs post-viral pneumonia, with special attention to CAM and corticosteroid use. It is important to have a clear understanding of the pathophysiology for better prevention, early diagnosis, and management of viral pneumonia.4,22