意識障害と神経心理学的所見の異常を認めたレジオネラ肺炎の1例

Neuropsychological characteristics of a patient with consciousness disturbance caused by Legionella pneumonia

　レジオネラ肺炎では約18〜47％に意識障害を生じるが，意識障害と神経心理学的所見について検討した報告はない．今回レジオネラ肺炎に伴い意識障害を生じた症例に言語聴覚士が介入し，認知機能低下など神経心理学的所見の異常を捉えることができたため報告する．症例は70歳の男性．発熱，酸素化低下，意識障害があり肺炎を認め入院した．入院2日目に肺炎が悪化し，尿中レジオネラ抗原陽性からレジオネラ肺炎と診断し治療を行った．見当識障害は改善したが，意識障害または認知機能低下が疑われ入院5日目の神経心理学的検査で認知機能低下を認めた．入院10日目には肺炎は治癒し認知機能低下は改善したが，流暢性，分割注意・複数課題処理能力，概念・セットの転換の障害の残存を認めた．レジオネラ肺炎に伴い意識障害を生じた症例では神経心理学的所見の異常がしばらく持続する可能性があるので，言語聴覚士は継続的に神経心理学的所見を検索するべきである．

　Although consciousness disturbance occurs in 18-47％ of cases of Legionella pneumonia, no report has detailed the neuropsychological features in patients with Legionella pneumonia and consciousness disturbance. Herein, we present the neuropsychological characteristics of a patient with Legionella pneumonia, as assessed by speech-language-hearing therapists. A 70-year-old man with fever, consciousness disturbance, and oxygen desaturation was admitted to our hospital with pneumonia. One day after hospitalization, the patient's pneumonia deteriorated. He was diagnosed with Legionella pneumonia based on a positive urinary test for the Legionella antigen and received treatment for the condition. On the 5th day of admission, although the patient's disorientation improved, neuropsychological assessments revealed a cognitive disturbance. On the 10th day of admission, he had recovered from pneumonia. Although the patient's cognitive impairment improved, disturbances in fluency, impairment of divided attention, and difficulty in shifting categories or sets persisted. In some patients with Legionella pneumonia and consciousness disturbance, abnormal neuropsychological findings may exist and persist for some time, necessitating ongoing neuropsychological assessments by speech-language-hearing therapists.