The Mycelial Mire-Mucormycosis

Abstract

Mucormycosis is an infrequent, angio-invasive, fatal fungal infection incriminating immunocompromised individuals. Mucormycosis commonly arises due to infection with rapidly progressive, pauci-septate moulds or fungal species such as Rhizopus, Mucor, Lichtheimia (Absidia) or Entomophthorales. Mucormycosis is a significant, secondary fungal infection associated with SARS-CoV-2 infection wherein pulmonary mucormycosis and rhinocerebral mucormycosis are commonly engendered. Especially, a triad of mucormycosis, diabetes mellitus and prolonged corticosteroid therapy is exemplified in subjects with COVID-19. Elevated plasma glucose, reduced pH, free iron and ketones along with decreased white blood cell phagocytic activity amplifies propagation of mucor. Mucormycosis commences with inhalation or ingestion of environmental spores which are subsequently phagocytosed within polymorphonuclear cells. Mucormycosis appears within the nasal cavity, paranasal sinuses, orbit, central nervous system (CNS), pulmonary parenchyma, gastrointestinal tract (GIT), cutaneous surfaces, jaw bones, joints, cardiac muscle, renal parenchyma and mediastinum. Infiltration with giant cells, vascular thrombosis and eosinophilic necrosis of encompassing soft tissue is pathognomonic of mucormycosis. Serological assessment with enzyme linked immunosorbent assay (ELIZA), immunoblot or immunodiffusion assays and molecular assays as polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) or DNA sequencing techniques are optimal for diagnosing mucormycosis. Appropriate therapy of mucormycosis is contingent to antecedent commencement of antifungal agents, treatment of comorbid conditions and debridement of infected tissue.