Avaliação da atividade antifúngica de pentamidina frente a cepas do complexo Sporothrix schenckii na forma leveduriforme

Abstract

Sporotrichosis is caused by dimorphic fungi belonging to the Sporothrix schenckii complex. This disease can mimic several other diseases of dermatological involvement, among them leishmaniasis. The differential diagnosis between these diseases can be a challenge and misdiagnosis can lead patients with sporotrichosis to misuse of leishmanicidal drugs. The objective of this study was to evaluate the antifungal activity of leishmanicide pentamidine (PNT) against planktonic cells of Sporothrix schenckii species in yeast form. We used 19 strains of Sporothrix spp. (10 S. brasiliensis, 02 S. globosa, 04 S. mexicana and 03 S. Schenckii sensu stricto). The sensitivity tests were performed on microplates of 96 wells, according to the Clinical and Laboratory Standards Institute (CLSI), M27-A3, with some adaptations. For the trials with the planktonic form, the glasses were prepared in saline solution and then adjusted for a last concentration of 0.5-2.5 × 103

ufc/ml. Subsequently, the microplates were incubated at 37 oC for 96h. The minimum inhibitory concentration (MIC) of PNT was defined as the lowest concentration capable of inhibiting 50%, 80% and 100% of growth, for antifungal agents, the mic was defined as the lowest concentration able to inhibit 100% anfotericina B (AMB) and itraconazol (ITC) or 80% terbinafina (TRB) of fungal growth compared to the growth of the drug-free control. The PNT drug presented antifungal activity, with minimal inhibitory concentration (MIC) varying from 0.06 to 0.25 μg/ml for the yeast forms of Sporothrix spp. It was concluded that the PNT showed antifungal activity in front of planetotonic cells Sporothrix spp.