陽イオン界面活性剤を含む家畜用消毒薬の誤飲により上気道狭窄後嚥下障害が残存した2症例(Two cases of sustained upper airway stenosis and persistent dysphagia after accidental ingestion of livestock disinfectant containing cationic surfactant)

要旨 粘膜腐食作用を持つ陽イオン界面活性剤誤飲後，上気道狭窄を生じ，さらに嚥下障害が残存した2例を経験した。症例1は知的障害を有する47歳の男性。就業中に家畜用消毒薬を約200mL誤飲し，近医で応急処置後当院へ転院となった。来院時上気道狭窄を認め，経口気管挿管が困難であったため，緊急外科的気道確保を行った。造影CTにて咽喉頭および全食道粘膜に強い浮腫像を認め，絶飲食管理で入院した。CTや内視鏡で粘膜障害のフォローを行い，第20病日に消化管粘膜の正常化を認めたが，喉頭は両披裂部と梨状窩の癒合を認め嚥下障害を伴った。嚥下訓練を開始したが完治せず，第58病日に転院した。症例2は知的障害を有する59歳の男性。症例1と同経緯で消毒薬約10mLを誤飲し，当院へ転院となった。来院時努力様呼吸と嗄声を認め，造影CTにて声門・披裂部と食道粘膜に中等度の浮腫像を認めた。CT後上気道狭窄を呈し，経口気管挿管を行った。入院後も喉頭浮腫は遷延し，第6病日に気管切開術を施行した。第13病日に消化管粘膜は正常化し，第18病日には気道粘膜も肉眼的に正常化したが，嚥下障害を呈した。嚥下訓練実施後も改善せず誤嚥性肺炎を繰り返し，第106病日に転院した。本症例で誤飲した陽イオン界面活性剤は高濃度（20%）であり，気道・消化管粘膜障害のほか，嚥下障害が生じ残存したと思われた。 ABSTRACT Cationic surfactant has a strong mucosal corrosive action. We describe two cases of sustained upper airway stenosis and persistent dysphagia after accidental ingestion of 20% high–concentration livestock disinfectant containing cationic surfactant. Case 1 was a 47–year–old man and case 2 was a 59–year–old man with intellectual disability. They accidentally ingested approximately 200mL (case 1) and 10mL (case 2) disinfectant during work and were transferred to the hospital. Case 1 developed upper airway stenosis and was intubated with difficulty on hospital arrival; he required surgery for establishment of an emergent airway. Contrast computed tomography (CT) showed severe edema in the membranes of the laryngopharynx and the whole esophagus. On day 20, we detected adhesion between the piriform recess and arytenoid region; the patient developed dysphagia. He did not recover fully despite receiving swallowing training. Case 2 experienced difficulty in breathing and hoarseness on hospital arrival, requiring intubation. Contrast CT showed a moderately edematous glottis, arytenoid, and esophagus. On day 6, tracheotomy was performed because of persistent laryngeal edema. On day 18, amelioration of airway mucosal edema was observed visually. However, despite swallowing training, he developed dysphagia that resulted in aspiration pneumonia.