Fatal Angioinvasive Mucormycosis ‘Black Fungus’, A Co-Infection in Covid-19 Patients, Requiring a Vigilant Eye Watch

Abstract

The pandemic of Corona viral infection disease-19 (COVID-19) had become a challenging task for the clinicians around the Globe. Despite the passage of near about one and a half year, yet many mysterious requires exploration to contain this fatal infection. The researchers and scientist are trying level best to identify ways for the reduction of morbidity and mortality rates from the said infection. But with the availability of vaccine things are heading towards betterment.

The COVID patients are found to be at risk of many serious complications. Presence of serious fungal infections is one of them. Few published studies are highlighting strong correlation amongst presence of superimposed angioinvasive Mucormycocsis (black fungus) in either acute illness or even in recovered patients. This rapidly progressing infection attacks the blood vessel and live tissues resulting in necrosis and blackening of area. Thus, giving it a name ‘black fungus’. This superimposed infection requires somber attention, because it prolongs the recovery time of patients. The negligence can even lead to fatal outcomes.¹ The early case recognition and timely management for mucormycosis will be the only way out to reduce the miseries of COVID sufferers. Mucormycosis or Zygomycosis (older name), belongs to a category of opportunistic invasive fungal infection (IFIs). Either of the three commonly responsible fungi i.e Rhizopus, Mucor, or Lichtheimia belongs to the phylum Zygomycota, subphylum Mucoromycotina, order Mucorales and the family Mucoraceae. The members of this order are also well known as Pin molds. These are congregated as saprophytic molds in environment like soil , putrefying organic matter i.e dung piles, vegetable matter, leaves, rotten wood, etc.² Mucormycosis is a third communal, rare and fatal angioinvasive fungal infection i.e 2–6% of all IFIs. However, candidiasis and aspergillosis rank on first and second numbers. According to a published report for the year 2021, species wise frequency in patients with mucormycosis is 34% for Rhizopus species, 19% for both Mucor and Lichtheimia species. The reported mortality rate showed a range of 50% - 80% especially for the intraorbital or intracranial complications. However, country wise variation was observed as well. In India, Rhizopus, Apophysomyces elegans, Anabaeana variabilis and Rhizopus homothallicus, were identified to be the evolving responsible species. While less frequently identified species includes Mucor irregularis and Thamnostylum lucknowense. A Mexican study reported a new commonly responsible species of Apophysomyces i.e Apophysomyces mexicanus.³ Other less frequently reported fungal infections includes oropharyngeal candidiasis, candidemia, pulmonary aspergillosis and pneumocystis jiroveci pneumonia.⁴ Mucormycosis is usually a coinfection in conditions like pulmonary diseases, renal disorders, septic arthritis, dialysis-associated, peritonitis, gastritis, rhinocerebral and cranifacial mycormycosis. The involvement of mucous layer of skin, precisely cutaneous layer, predisposes to mucormycosis...........................................