In vitro algaecid effect of itraconazole and ravuconazole on Prototheca species

Protothecosis is a rare infection in humans, dogs, and cats, and its causative agent is Prototheca species, which consists of achlorophyllic algae that are ubiquitous in natural environments and hosts intestinal flora. Ravuconazole (RVZ) is a new available human azole drug in Japan since 2018 and broad-spectrum antifungal agent. In the present study, the in vitro susceptibility of clinical and environmental isolates of P. wickerhamii, P. zopfii, and P. blaschkeae to itraconazole (ITZ) voriconazole (VRZ), posaconazole (PCZ), and RVZ. RVZ was more potent than the other azoles against Protheca species and has considerable potential for use as a therapeutic agent for human and animal protothecosis.