COPDを基礎疾患とした帯状疱疹後横隔神経麻痺の1例

Acute Respiratory Failure with Unilateral Diaphragmatic Paralysis by Herpes Zoster Infection in a Patient with COPD

要旨　症例は86歳の男性，呼吸困難を主訴に当院救急搬送された．来院時酸素マスク9l/min投与下でSpO₂ 96%と低酸素血症を呈し，胸部X線写真にて以前には見られなかった右横隔膜拳上を認めた．横隔神経電気生理学的試験を施行し，右横隔神経麻痺と診断した．入院前に右頸部C3-4レベルの帯状疱疹に罹患していたことから帯状疱疹による右横隔神経麻痺を原因とした急性呼吸不全と考えた．また，基礎疾患として慢性閉塞性肺疾患(COPD)を認めた．頸部帯状疱疹罹患後横隔神経麻痺を合併することがあり，呼吸不全の原因となる可能性がある．

　An 86-year-old man developed dyspnea and was transferred to our hospital by ambulance. On arrival he was hypoxic, and chest X-ray showed an elevation of right diaphragm. Motor nerve condution study of right phrenic nerve showed a depressed amplitude, and he was diagnosed with right diaphragmatic paralysis. Herpes zoster infection, which had caused vesicular eruption on his right neck 2 weeks before his admission, was considered as the etiology of diaphragmatic paralysis. Pulmonary function test showed obstructive pattern, and suggested that he had chronic obstructive lung disease(COPD)due to his heavy smoking history. It should be noted that diaphragmatic paralysis caused by herpes zoster infection could lead to acute respiratory failure especially in patients with underlying lung diseases.