CARD9 mutation linked to Corynespora cassiicola infection in a Chinese patient

Summary Corynespora cassiicola is a plant pathogen associated with leaf‐spotting disease. The fungus has been found on diverse substrates: leaves, stems and roots of plants; nematode cysts and human skin. It rarely causes human infections. Here we report one case of subcutaneous phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis in a woman. All of her clinical features pointed towards a genetic linkage. Hence, whole‐exome sequencing and Sanger sequencing were performed on this patient. One mutation of CARD9 was detected. What's already known about this topic? Cases of phaeohyphomycosis caused by Corynespora cassiicola are rare. Genetic susceptibility to fungal diseases in otherwise healthy patients has gained interest in recent years. In particular, various inborn errors of genes have been reported to underlie chronic mucocutaneous candidiasis disease and other cutaneous dermatophytoses. What does this study add? We present a female patient with phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis. Molecular evidence of mutation in CARD9 is provided for C. cassiicola infection.