以空氣新月徵兆作診斷的侵入性肺麴菌感染

Invasive Pulmonary Aspergillosis with Air Crescent Sign

侵襲性肺部麴菌病（invasive pulmonary aspergillus，IPA）診斷具有其挑戰性，且近年因新型癌症治療、長期類固醇使用及病毒性肺炎等風險因子增加，發生率有上升趨勢。本案例為55歲下咽癌（cT2N2bMo，stage IVA）男性，曾接受同步化學與放射治療，因發燒（39.3°C）、咳嗽及化膿性痰液住院。白血球增多，胸部X光顯示右上肺葉有實質病變，初步診斷為社區型肺炎，經抗生素治療無效，症狀加劇。胸部X光與電腦斷層顯示右上肺實質病變惡化並形成空洞，出現空氣新月徵象（air crescent sign）。痰液培養未發現致病菌，血清麴菌半乳甘露聚醣抗原（galactomannan，GM）指數升高至0.7及支氣管肺泡灌洗液（bronchoalveolar lavage，BAL）檢查GM指數亦高達4.764，確診為IPA。接受voriconazole與levofloxacin治療後症狀改善，GM指數下降，改口服藥物出院，後續門診追蹤穩定，顯示及早診斷與適當治療的重要性。

The diagnosis of invasive pulmonary aspergillosis (IPA) is challenging, and its incidence has been increasing in recent years due to emerging risk factors such as novel cancer therapies, prolonged corticosteroid use, and viral pneumonia. This case involves a 55-year-old male with hypopharyngeal cancer (cT2N2bM0, stage Iva), who had previously undergone concurrent chemoradiotherapy. He was hospitalized due to fever (39.3°C), cough, and purulent sputum. Laboratory tests revealed leukocytosis, and chest X-ray showed consolidation in the right upper lobe. Initially diagnosed as community-acquired pneumonia, he did not respond to empirical antibiotic therapy, and symptoms worsened. Follow-up chest X-ray and CT scan showed progression of the consolidation with cavitation and the presence of the air crescent sign. Sputum cultures were negative for pathogens. However, serum galactomannan (GM) was significantly elevated at 0.7, and bronchoalveolar lavage (BAL) GM index was also increased to 4.764, confirming the diagnosis of IPA. After treatment with voriconazole and levofloxacin, his symptoms improved and GM index decreased. He was discharged on oral voriconazole and remained stable during outpatient follow-up, highlighting the importance of early diagnosis and appropriate treatment in managing IPA.