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 各疾患の遺伝子異常，診断と治療

先天性好中球減少症

著者： 岡田賢¹ 小林正夫²

所属機関： ¹広島大学病院小児科 ²広島大学大学院医歯薬学総合研究科小児科学

ページ範囲：P.587 - P.592

　先天性好中球減少症は慢性好中球減少，前骨髄球～骨髄球の段階での成熟障害を臨床的特徴とし，生後早期から重症細菌感染症を反復する先天性免疫不全症である．近年，種々の責任遺伝子が同定され，本症の分子レベルでの病因が明らかとなりつつある．本疾患では，好中球エラスターゼの責任遺伝子ELA2の異常を高頻度に認めることが知られていたが，2007年にHAX1が新規の責任遺伝子として報告された．われわれのわが国における患者解析では，ELA2変異が約70%に，HAX1変異が約20%に同定された．さらに興味深いことにHAX1変異を有する患者では，好中球減少症以外の症状として神経学的異常が認められることが特徴的であった．本稿では，先天性好中球減少症の最近の知見を概説する．

参考文献

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