Resolving the equation between mucormycosis and COVID-19 disease

Abstract

The COVID-19 patients, both infected and recovered are rapidly contracting mucormycetes infections due to the ‘Mucorales’ order, under Zygomycetes class of fungi. The mucorales fungi commonly known to exist in our natural surroundings including soil, but the frequency of incidences was never rampant. This sudden spike in infections, is locally known as ‘black fungus,’ and is affecting various organs, including- eyes, sinuses, nose, brain, skin, intestine, lungs, etc. The severity of situation is ascertainable from the fact that, in certain cases surgical eye/jaws removal persists as the only viable option to avert mortality, as therapeutic interventions are limited. This epidemic situation intrigued experts to investigate the probable reason behind this unpredicted escalation in reported cases, including in recuperated COVID-19 patients, as person-to-person spread of infection is not common. The comparison of physiological parameters in healthy and COVID-19 afflicted patients highlights that the underlying conditions including diabetes mellitus, steroidal therapy, lymphopenia (decreased CD4+ and CD8+ lymphocytes), deregulated cytokine release storm, elevated free iron levels (hemosiderosis) in blood and insulin insensitivity are playing major roles in deteriorating conditions in rarely pathogenic fungal infections. This review is an attempt to explain the rationalities that makes people vulnerable to mucormycetes infection.

Commentary: A Machine-Generated View of the Role of Blood Glucose Levels in the Severity of COVID-19. A Metabolic Endocrinology Perspective

“…The other COVID-associated pandemic is mucormycosis, a normally rare infection caused by a fairly ubiquitous filamentous mold fungus ( 50 ). However, large numbers of cases have been reported in patients with COVID-19 ( 51 ): as with COVID-19, males appear to be at greater risk ( 52 ). Predominantly the cases have been within India, which reported over 45,000 cases and 4,300 deaths between April and July of 2021 ( 51 ); but cases have also been reported globally ( 52 ).…”

“…However, large numbers of cases have been reported in patients with COVID-19 ( 51 ): as with COVID-19, males appear to be at greater risk ( 52 ). Predominantly the cases have been within India, which reported over 45,000 cases and 4,300 deaths between April and July of 2021 ( 51 ); but cases have also been reported globally ( 52 ). The infections have mostly been rhino-orbital mucormycosis which has a mortality rate as high as 30-50% with limited treatment options frequently necessitating the removal of the eyes ( 52 , 53 ).…”

“…Predominantly the cases have been within India, which reported over 45,000 cases and 4,300 deaths between April and July of 2021 ( 51 ); but cases have also been reported globally ( 52 ). The infections have mostly been rhino-orbital mucormycosis which has a mortality rate as high as 30-50% with limited treatment options frequently necessitating the removal of the eyes ( 52 , 53 ). Prior to COVID-19 it had been established that infection with mucormycosis was facilitated by a combination of conditions including being immunocompromised, hyperglycemia and acidosis, particularly ketoacidosis ( 54 ).…”

“…Mucormycosis infection proceeds via an interaction between a fungal spore coat protein and cell surface receptors in the nasal passage that have been identified as glucose-regulated protein 78 (GRP78) ( 52 , 54 ). GRP78 is as a protein chaperone that facilitates proteins entering the cell via endocytosis ( 55 , 56 ); its abundance is induced by glycemic stress ( 57 , 58 ) and inflammatory cytokines stimulate its translocation to the cell surface ( 59 ).…”

Sensitivity of liquid‐based cytology in the diagnosis of mucormycosis in COVID‐19 treated patients

“… 7 Fungal cells require iron for angioinvasion, which is generally bound to iron binding proteins; acidosis results in dissociation of iron from the sequestering protein and thus promotes angioinvasion. 8 …”