COVID-associated mucormycosis (CAM): is the Delta variant a cause?

Intratemporal mucormycosis: a rare COVID-19 sequelae

A man in his 50s presented with a 2-month history of left ear discharge associated with hearing loss and weakness of left half of face since 15 days. The patient had no comorbidities, but he gave history of being treated for COVID-19 pneumonia 2 months ago post which he started experiencing left-sided aural symptoms. Clinical examination of ear revealed a subtotal perforation with multiple granulations in middle ear. Facial nerve examination revealed grade 3 lower motor neuron palsy. The biopsy of the granulations was sent to aid in diagnosis which later confirmed left ear mucormycosis. Otological involvement with facial palsy and sudden sensorineural loss in a patient with prior history of COVID-19 has not been reported until in literature. We try to communicate our experience to bridge the gap in understanding and managing this extremely rare occurrence of mucormycosis in the ear of a patient diagnosed with COVID-19 infection.

Mucormycosis and COVID-19-Associated Mucormycosis: Insights of a Deadly but Neglected Mycosis

The ongoing COVID-19 pandemic has quickly become a health threat worldwide, with high mortality and morbidity among patients with comorbidities. This viral infection promotes the perfect setting in patients for the development of opportunistic infections, such as those caused by fungi. Mucormycosis, a rare but deadly fungal infection, has recently increased its incidence, especially in endemic areas, since the onset of the pandemic. COVID-19-associated mucormycosis is an important complication of the pandemic because it is a mycosis hard to diagnose and treat, causing concern among COVID-19-infected patients and even in the already recovered population. The risk factors for the development of mucormycosis in these patients are related to the damage caused by the SARS-CoV-2 itself, the patient’s overstimulated immune response, and the therapy used to treat COVID-19, causing alterations such as hyperglycemia, acidosis, endothelial and lung damage, and immunosuppression. In this review, the molecular aspects of mucormycosis and the main risk factors for the development of COVID-19-associated mucormycosis are explained to understand this virus–fungi–host interaction and highlight the importance of this neglected mycosis.

Pathogenesis of Respiratory Viral and Fungal Coinfections

Individuals suffering from severe viral respiratory tract infections have recently emerged as "at risk" groups for developing invasive fungal infections. Influenza virus is one of the most common causes of acute lower respiratory tract infections worldwide. Fungal infections complicating influenza pneumonia are associated with increased disease severity and mortality, with invasive pulmonary aspergillosis being the most common manifestation. Strikingly, similar observations have been made during the current coronavirus disease 2019 (COVID-19) pandemic. The copathogenesis of respiratory viral and fungal coinfections is complex and involves a dynamic interplay between the host immune defenses and the virulence of the microbes involved that often results in failure to return to homeostasis. In this review, we discuss the main mechanisms underlying susceptibility to invasive fungal disease following respiratory viral infections. A comprehensive understanding of these interactions will aid the development of therapeutic modalities against newly identified targets to prevent and treat these emerging coinfections.