Cutaneous and Subcutaneous Hyalohyphomycosis Caused by Purpureocillium Lilacinum in a Tertiary Referral Hospital in Central China

Abstract

Purpureocillium lilacinum, a saprobic filamentous fungus with a global distribution, is an emerging opportunistic pathogen, but its clinical and microbiological profile in China is not well characterized. This study retrospectively analyzed three cases of Purpureocillium lilacinum hyalohyphomycosis in central China and reviewed 7 additional cases from mainland China (2010–2025). The diagnosis was made through a meticulous integration of histopathological analysis, cultivation characteristics, Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), and internal transcribed spacer (ITS) sequencing. All isolates had high minimum inhibitory concentrations (MICs) to amphotericin B, echinocandins, and fluconazole. Voriconazole and posaconazole showed the highest in vitro activity (MICs 0.12–1 mg/L and 0.25–0.5 mg/L, respectively), while itraconazole susceptibility varied (MIC 0.5–4 mg/L). Rapid and accurate identification requires confirmation via histopathology combined with MALDI-TOF MS or molecular diagnostic methods. Successful management relies on early suspicion, susceptibility-guided therapy with voriconazole and posaconazole, and surgical intervention when appropriate.