1．侵襲性アスペルギルス症—早期診断・早期治療のためのストラテジー

Invasive aspergillosis

アスペルギルスは，自然界の多様な環境で生存可能な真菌である。病院改築を契機としたアウトブレイクを起こすこともある。臨床的にアスペルギルスは，①侵襲性アスペルギルス症，②慢性肺アスペルギルス症，③アスペルギローマ（定着状態），④アレルギー性気管支肺アスペルギルス症の4つに分類されるが，それぞれの病態が重なることもある。以下本稿では，侵襲性アスペルギルス症（IA）の特徴，診断検査，治療について，EORTC/MSG診断基準やIDSAのガイドラインなどをもとに解説する。

Invasive aspergillosis （IA） is a fungal infection which develops in severely immunodeficient patients, and commonly involves the lungs. Biopsy confirmation is necessary to prove the diagnosis, but it is frequently difficult because these procedures have risks for complications and culture and histopathological examination have low sensitivity. To estimate the probability of IA, host factors, clinical signs and biomarkers should all be considered. Among patients at low risk for IA, serum biomarkers may be falsely positive due to a very low prevalence, so initiation of treatment should be decided carefully. In severely immunocompromised patients, especially patients with prolonged neutropenia, empiric antifungal therapy or preemptive therapy is effective to reduce mortality when fever is prolonged despite receiving broad-spectrum antibiotic therapy. Voriconazole is recommended as initial therapy, a lipid formulation of amphotericin B and isavuconazole are alternatives. This review provides an algorithm for the diagnosis and management of IA.