二次性の食道運動障害（膠原病や好酸球性食道炎に伴うもの）

Secondary Esophageal Motility Disorders（Associated with Collagen Disease or Eosinophilic Esophagitis）

要旨●二次性の食道運動障害を来す疾患としては，全身性強皮症などの膠原病や神経筋疾患，代謝性疾患など種々の疾患が知られている．食道胃接合部の狭窄を認める症例では，食道癌などの悪性腫瘍の鑑別が重要である．全身性強皮症では食道運動障害が高率に認められ，食道運動障害に伴うクリアランス低下から薬剤抵抗性逆流性食道炎を呈することも少なくない．好酸球性食道炎では食道運動障害が認められることが多く，つかえ感や胸痛などの症状は食道運動障害が原因になっている．特に，食道の収縮異常だけではなく，伸展不良も重要であり，病態として好酸球浸潤に伴う炎症とリモデリングが関与している．

　Secondary esophageal motility abnormalities could be observed in patients with collagen diseases, such as systemic sclerosis, neuromuscular diseases, and metabolic diseases. Moreover, it is important to rule out diseases, such as malignant esophageal cancer. Esophageal motility abnormalities are often seen in patients with systemic sclerosis that result in poor esophageal acid clearance, causing medication-refractory reflux esophagitis. Esophageal motility abnormalities are also frequently observed in patients with eosinophilic esophagitis, evoking symptoms, such as dysphagia or chest pain. Patients with eosinophilic esophagitis not only present with abnormal esophageal contractions but also present reduced esophageal distensibility. Moreover, eosinophilic inflammation and remodeling could be involved in the pathogenesis of eosinophilic esophagitis.