Rhizopus e mucormicose: fatores de risco, patogenicidade e novas opções de tratamento.

Abstract

Zygomycosis is an infection caused by fungi from class Zygomycetes, which has a high mortality rate. According to the order which belongs the fungus causing the disease; Mucorales and Entomophthorales, zygomycosis can also named mucormycosis or entomophthoromycosis. One of the main genuses of fungi that cause infection are Rhizopus, belonging to the order Mucorales. The main clinical forms of mucormycosis caused by Rhizopus spp. are the forms: pulmonary, rhinocerebral, cutaneous and gastrointestinal. The research on the key mechanisms of pathogenicity of this fungus, the major risk factors that make a major cause of mucormycosis and new treatment options, was the objective of this work. The material used in this review was obtained by searching in databases free data as SciELO, PubMed, Bireme, Science Direct, Lilacs, Medline and Medscape. The main risk factors associated with infection by Rhizopus spp. are associated with failures in the immune system, as occurs in transplant patients, who are making use of corticosteroids or chemotherapy. Diabetes mellitus also proved to be an important risk factor for mucormycosis. Diabetic ketoacidosis is the most important risk factor because accentuates pathogenic characteristics of Rhizopus spp. as angioinvasion and iron uptake. The standard treatment of mucormycosis is done with amphotericin B was shown to be nephrotoxic. Some authors reported the antifungal activity against Rhizopus spp. new substances, such as colistin, chitosan and thymol . Other studies have shown efficacy in the treatment using combinations of known antifungal agents. To make possible the development of new therapeutic options is necessary to better understanding the mechanisms of pathogenicity of Rhizopus spp. and subsequent correlation with host risk factors.