熱に安定した腸毒素を生成するEscherichia coli菌株に関連した下痢
Lancet (London, England)
|August 9, 1975
まとめ
エントロトキシゲン性Escherichia coliは,熱安定性エンテロトキシン (ST) のみを生成する. 急性水性下痢の患者で確認されました. これらの細菌は,以前は動物に影響することが知られていましたが,現在はヒトの病原体として認識されています.
科学分野:
- 微生物学 微生物学とは
- 感染症 感染症は感染症です.
- 胃腸内科 胃腸内科
背景:
- エントロトキシゲン性Escherichia coli (ETEC) は,世界中で下痢性疾患の重要な原因である.
- ETEC菌株は熱可動性腸内毒素 (LT) や熱安定性腸内毒素 (ST) を生成する.
- これまで,ヒトの感染症におけるSTのみを産生するETECの役割はあまり理解されていませんでした.
研究 の 目的:
- メキシコから帰国した旅行者の急性水性下痢の原因を調査する.
- 感染した患者からのEscherichia coli単離物の腸内毒素プロフィールを特徴付ける.
主な方法:
- 便サンプルは,急性水性下痢を呈する5人の患者から採取された.
- エントロトキシゲン性Escherichia coliが隔離され,特定されました.
- エントロトキシン産生 (熱安定性および熱可変性) を評価した.
主要な成果:
- エントロトキシゲン性Escherichia coliは5人の患者全員で確認されました.
- すべての単離体は熱安定性腸毒素 (ST) を独占的に生成した.
- 熱反応性腸内毒素 (LT) は,大腸菌菌株のいずれにも検出されなかった.
結論:
- STのみを生成するETEC菌株は,ヒトにとって病原性である.
- これらの発見は,ETECに関連したヒト感染症の既知のスペクトルを拡大します.
- 旅行者の下痢は,以前は主に動物病原体と考えられていたETEC菌株によって引き起こされる可能性があります.
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