A case of Jackhammer esophagus caused by eosinophilic esophagitis in which per-oral endoscopic myotomy resulted in symptom improvement.

A 73-year-old female with a 6-month history of progressive dysphagia and chest pain was referred to our hospital. She underwent esophagogastroduodenoscopy, which revealed abnormally strong contractions in the distal esophagus. Esophageal biopsy specimens showed massive eosinophil infiltration into the epithelium, and high-resolution manometry (HRM) also demonstrated abnormally strong contractions in the distal esophagus. Based on these results, she was diagnosed with Jackhammer esophagus (JHE) due to eosinophilic esophagitis (EoE). Treatment was started with 5 mg/day of prednisolone (PSL), and the number of peripheral blood eosinophils quickly decreased without any improvement in the patient's dysphagia. Esophageal biopsy specimens obtained after the PSL treatment showed the disappearance of eosinophils from the epithelium. However, abnormally strong contractions were still detected on HRM. Per-oral endoscopic myotomy (POEM) was performed to treat the JHE. Interestingly, the intraoperative esophageal muscle biopsy sample demonstrated massive eosinophil infiltration into the muscle layer. After the POEM, the patient's symptoms improved, and abnormal contractions were no longer detected on HRM. The current case suggests that when EoE combined with an esophageal motility disorder are refractory to steroid therapy, clinicians should be aware that motility disorders can develop due to eosinophil infiltration deep into the esophageal muscularis propria.