Abstract
We report a case of chromoblastomycosis which resembled sporotrichosis due to the presence of warty nodules and lymphatic distribution on the forearm in a 56-year-old male. Mycological and histopathological investigation of exudates and biopsy tissue samples revealed a granulomatous lesion with muriform cells, the hallmark of chromoblastomycosis. The infection showed only localized expansion with verrucous plaques suggesting a new clinical type of the disease. The causative agent was identified as Rhinocladiella aquaspersa. This case prompted a study of the clinical spectrum of R. aquaspersa, through which we identified a second case caused by this fungus in a 62-year-old Brazilian female. The case was unusual in that R. aquaspersa exhibited hyphae rather than muriform cells in tissue. Given the difficulties treating chromoblastomycosis and other infections caused by melanized fungi, we evaluated the in vitro activities of extended-spectrum triazoles, amphotericin B, and echinocandins against these clinical isolates of R. aquaspersa. Itraconazole (MIC; 0.063 mg/l) and posaconazole (MIC; 0.125 mg/l) had the highest in vitro activities, while voriconazole and isavuconazole had somewhat lower activities (MICs; 2 mg/l) against the isolates. Amphotericin B and anidulafungin each had an MIC of 1 mg/l, whereas the MIC of caspofungin was 8 mg/l.
Acknowledgements
This work was financially supported by a grant from the Iranian Ministry of Health and the Medical Education of Islamic Republic of Iran (No. 13081) and the School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran, which we gratefully acknowledge. The authors would like to thank Walter Gams and Dr Mark Jones (Basilea Pharmaceutica International AG, Basel, Switzerland) for critically reviewing the manuscript.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
This paper was first published online on Early Online on 27 January 2010.