テルビナフィン耐性トリコフィトン spp の流行に関する調査 スクアレンエポキシダース変異
Yugo Mori1, Tsuyoshi Yamada2, Sayaka Ban1
1Medical Mycology Research Center, Chiba University.
Medical mycology journal
|August 31, 2025
まとめ
テルビナフィンの耐性菌は,特にTrichophyton種のT. rubrumを超えて増加しています. この研究では,日本における耐性菌株を特定し,タービナフィンおよびアゾール耐性を誘発するスクラレンエポキシダース遺伝子の重要な変異を明らかにした.
科学分野:
- 医学菌学
- 抗菌剤に対する耐性
- 皮膚植物症の治療
背景:
- テルビナフィン (TBF) とアゾールは,真菌性皮膚感染症の主要な治療法です.
- TBFに耐性のあるトリホフィトン種の報告が増加し,トリホフィトン・ルーブルム以外の種の研究は限られている.
- T.interdigitale,T.mentagrophytes,T.indotineaeなどの研究されていないトリコフィトン種の耐性を理解する必要がある.
研究 の 目的:
- 日本におけるTBF耐性トリコフィトン単離物の有病率を決定する.
- 遺伝子変異を含む耐性メカニズムを研究する.
- アゾール抗菌剤との共抗性のパターンを評価する.
主な方法:
- 日本からの701の臨床トリコフィトン単離物のスクリーニング
- TBFの最小抑制濃度 (MIC) の決定
- スクアレンエポキシダース遺伝子の配列を解析し,TBF耐性に関連する変異を特定する.
主要な成果:
- 2. 9% (20/ 701) のTBF耐性菌株の流行が確認された.
- 耐性菌群にはT. rubrum,T. interdigitale,T. mentagrophytes,T. indotineaeが含まれていた.
- スクアレンエポキシダース遺伝子の重要な変異,特にPhe397は,高レベルのTBF耐性 (MIC ≥32μg/ ml) と関連していた.
- アゾールに対する共耐性は,T. rubrum,T. mentagrophytes,T. indotineaeで観察されました.
- アゾール感受性が低下した新しいTBF耐性T.メンタグロファイトが検出されました.
結論:
- この研究は,日本における様々なトリコフィトン種におけるTBF耐性の出現を強調しています.
- スクアレンエポキシダース遺伝子の特定の変異は,TBF耐性の決定的な要因です.
- TBFとアゾールに対する抗真菌耐性パターンの継続的な監視は,耐性単離物が増加しているため不可欠です.
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