Fast diagnosis of sporotrichosis caused by Sporothrix globosa, Sporothrix schenckii, and Sporothrix brasiliensis based on multiplex real-time PCR

摘要

Author summary Sporotrichosis is a subacute or chronic infectious disease caused by dimorphic fungi of Sporothrix spp. The genus Sporothrix consists of several species with different geographic distributions, virulence, and antifungal susceptibilities, making species-level identification necessary. S. brasiliensis, S. globosa, S. schenckii s. str and S. luriei make up the 'pathogenic clade' of the genus Sporothrix. Importantly, S. luriei has a low clinical-epidemiological impact within this genus. Therefore, we designed a novel multiplex real-time PCR method using fluorescent probes for the identification of S. globosa, S. schenckii s. str, and S. brasiliensis. We designed a pair of primers based on the conserved sequence of the calmodulin gene of Sporothrix spp. and probes with different fluorescent signals based on the divergent sequences of S. globosa, S. schenckii s. str and S. brasiliensis. Through the verification of nucleic acid, clinical and spiked sample detection, the multiplex real-time PCR could quickly and accurately identify the three clinically relevant species of Sporothrix spp. with high sensitivity. This new assay could be applied in epidemiology, clinical diagnosis, and experiments with sporotrichosis to control new outbreaks, reduce diagnostic and identification time, and improve test efficiency.