Insight into Covid Associated Mucormycosis: A Prospective Study

Area of Science:

• Infectious Diseases
• Otolaryngology
• Virology

Background:

• Rhino-orbito-cerebral mucormycosis cases surged during the COVID-19 pandemic.
• Both COVID-19 and mucormycosis share the nasal mucosa as an entry point, prompting investigation into shared receptor roles.
• Understanding these molecular interactions is crucial for managing co-infections.

Purpose of the Study:

• To compare the expression of ACE2 and TMPRSS2 receptors in nasal and paranasal sinus tissues.
• To analyze receptor expression in patients with COVID-19-associated mucormycosis (CAM), COVID-19-negative mucormycosis (CNM), and healthy controls.

Main Methods:

• Prospective study involving patients undergoing surgical management for CAM, CNM, and healthy individuals.
• Immunohistochemistry used to detect ACE2 and TMPRSS2 receptor presence in sino-nasal tissues.
• Statistical comparison of receptor levels across the three study groups.

Main Results:

• ACE2 receptor positivity was observed only in apical cilia, with no significant differences among groups (p=0.6).
• TMPRSS2 receptors were found in the cytoplasm, nucleus, epithelium, and submucosal glands.
• TMPRSS2 expression was significantly higher in CAM patients compared to CNM (p=0.009) and healthy individuals (p=0.002).

Conclusions:

• TMPRSS2 receptor expression is elevated in patients with COVID-19-associated mucormycosis.
• ACE2 receptor expression did not significantly change between groups.
• Elevated TMPRSS2 may contribute to heightened susceptibility to SARS-CoV-2 and subsequent Mucorales co-infection.