臨床検査53巻5号

2009年05月発行

今月の主題 免疫不全症候群と遺伝子異常 免疫不全症の臨床検査

TRECs測定による重症複合免疫不全症のマススクリーニング

著者： 森西洋一¹ 今井耕輔²

所属機関： ¹防衛医科大学校小児科 ²防衛医科大学校小児科・医療情報部

ページ範囲：P.553 - P.559

　重症複合免疫不全症(SCID)は，乳児期早期に重症日和見感染症を発症する致死的な先天性免疫不全症である．しかし，発症前に造血幹細胞移植が実施されれば高い生存率が期待できるため，早期の発見と介入が重要であり，その早期診断法として，T細胞新生能のマーカーであるTRECsの定量が有用とされる．健常人の末梢血中のTRECs値は，乳児期に最も高く加齢に伴い低下するが，胸腺内T細胞の分化・新生障害を共通病態とするSCIDでは，原因遺伝子による表現型の差異にかかわらず著減している．診断が遅れて難治化，あるいは死亡するSCIDの子供たちを救うためにも，TRECs定量による新生児マススクリーニングの整備が急務である．

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