Deep dermatophytosis caused by <i>Trichophyton rubrum</i> in an elderly patient with <scp>CARD9</scp> deficiency: A case report and literature review
Osamu Ansai, Ryota Hayashi, Anna Nakamura, Jin Sasaki, Akito Hasegawa, Tokiko Deguchi, Akihiko Yuki, Naoki Oike, Takashi Ariizumi, Masahiro Abe, Yoshitsugu Miyazaki, Tatsuya Takenouchi, Hiroyuki Kawashima, Riichiro Abe
Abstract
Deep dermatophytosis is an invasive and sometimes life-threatening fungal infection mainly reported in immunocompromised patients. However, a caspase recruitment domain-containing protein 9 (CARD9) deficiency has recently been reported to cause deep dermatophytosis. Herein, we report the first Japanese case of deep dermatophytosis associated with CARD9 deficiency. An 80-year-old Japanese man with tinea corporis presented with subcutaneous nodules on his left sole. Histopathological findings revealed marked epithelioid cell granulomas with filamentous fungal structures in the deep dermis and subcutis, and the patient was diagnosed with deep dermatophytosis. Despite antifungal therapy, the subcutaneous nodule on his left sole gradually enlarged, his left calcaneal bone was invaded, and the patient finally underwent amputation of his left leg. Genetic analysis revealed a homozygous CARD9 c.586 A > G (p. Lys196Glu) variant, suggesting a CARD9 deficiency. Here, we discuss the clinical features of CARD9 deficiency-associated deep dermatophytosis with a case report and review of the literature.