前腕に生じたTrichophyton interdigitaleによる生毛部急性深在性白癬

・副腎皮質ステロイド外用薬を長期間使用後に生じた前腕の生毛部急性深在性白癬を経験した．

・病理組織学的に真皮内に破壊された毛包とその周囲に膿瘍，肉芽腫を認めた．また膿瘍内にごく少数の菌要素を認めた．

・皮膚組織から培養されたコロニーを分子生物学的に検索した結果，Trichophyton interdigitale（T. interdigitale）と同定した．

・テルビナフィン塩酸塩内服にて治癒した．

（「症例のポイント」より）

　

Tinea corporis on the forearm caused by Trichophyton interdigitale

　

Kimura, Ryoko1）Yamada, Nanako1）Ito, Ayako1）Anzawa, Kazushi2）Mochizuki, Takashi2）Yamamoto, Osamu1）

1）Division of Dermatology, Department of Medicine of Sensory and Motor Organs, Faculty of Medicine, Tottori University

2）Department of Dermatology, Kanazawa Medical University

　

A 71-year-old Japanese man had been receiving topical corticosteroid treatment for erythroderma for the past 5 years. He presented with a 1-week history of small, light-yellow nodules on his right forearm. Histopathological examination showed destruction of hair follicles and perifollicular mixed-cellular inflammatory infiltration with granulomatous foci in the dermis. Grocott stain revealed only a few hyphae in the dermis. The isolate was identified as Trichophyton interdigitale by sequence analysis of the internal transcribed spacer regions of the ribosomal RNA gene. The skin lesions disappeared with oral administration of terbinafine of 125 mg daily for 3 weeks.