Paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a systemic, endemic disease limited to Latin American countries covering Mexico to Argentina, with Brazil accounting for most patients. Phylogenetic studies divide the Paracoccidioides genus into five species, Paracoccidioides brasiliensis, Paracoccidioides restrepiensis, Paracoccidioides americana, Paracoccidioides venezuelensis and Paracoccidioides lutzii. These fungi are thermally dimorphic and grow as moulds below 24 °C, while at 37 °C, they transition into yeasts, a morphotype also observed in patients. The P. brasiliensis complex’s natural habitat remains undefined, although it is expected to include soil in regions with high rainfall index, and the soils show optimal permeability. Paracoccidioides are potentially zoonotic and are found in armadillos, dogs and monkeys. In adults, mycosis predominantly afflicts males (13:1), but in children or adolescents, this gender difference is not observed. Infection can occur by inhalation of airborne conidia present in nature, but the long latency period and lack of reported outbreaks often hinder the definition of the primary infection. The acute–subacute (juvenile) and the chronic (adult) forms are the two types of clinical presentations being recognized. There is also recognition of a residual, non-mycotic active form characterized by fibrosis. The classical PCM diagnosis combines clinical evaluation and laboratory techniques, including direct examination, histopathology, culture-based techniques and immunological and molecular assays. To treat this mycosis, three classes of antifungals are presently used: sulphonamides, polyene amphotericin B and its lipid formulations and certain azoles. First- and second-generation azoles, such as itraconazole (the medication of choice) and voriconazole, have become therapeutic options for controlling mycosis.