SAPROPHYTIC PARASITE AND MYCOSIS BY BLACK FUNGUS

*Dr. Dhrubo Jyoti Sen, Kushal Nandi, Dr. Beduin Mahanti and Dr. Dhananjoy Saha

ABSTRACT

Mucormycosis, previously called zygomycosis, refers to several different diseases caused by infection with fungi in the order Mucorales. Rhizopus species are the most common causative organisms. In descending order, the other genera with mucormycosis-causing species include Mucor, Cunninghamella, Apophysomyces, Lichtheimia (formerly Absidia), Saksenaea, Rhizomucor, and other species. Most mucormycosis infections are life-threatening, and risk factors such as diabetic ketoacidosis and neutropenia are present in most cases. Severe infection of the facial sinuses, which may extend into the brain, is the most common presentation. Mucormycosis is a life-threatening infection that occurs in patients who are immunocompromised because of diabetic ketoacidosis, neutropenia, organ transplantation, and/or increased serum levels of available iron. Because of the increasing prevalence of diabetes mellitus, cancer, and organ transplantation, the number of patients at risk for this deadly infection is increasing. Despite aggressive therapy, which includes disfiguring surgical debridement and frequently adjunctive toxic antifungal therapy, the overall mortality rate is high. New strategies to prevent and treat mucormycosis are urgently needed. Understanding the pathogenesis of mucormycosis and the host response to invading hyphae ultimately will provide targets for novel therapeutic interventions. In this supplement, we review the current knowledge about the virulence traits used by the most common etiologic agent of mucormycosis, Rhizopus oryzae. Because patients with elevated serum levels of available iron are uniquely susceptible to mucormycosis and these infections are highly Angio invasive, emphasis is placed on the ability of the organism to acquire iron from the host and on its interactions with endothelial cells lining blood vessels. Several promising therapeutic strategies in preclinical stages are identified.

Keywords: Mucormycosis, previously called zygomycosis, refers to several different diseases caused by infection with fungi in the order Mucorales. Rhizopus species are the most common causative organisms. In descending order, the other genera with mucormycosis-caus