Buried mucosal incision site during poem closure giving false sense of security. All is not well beneath though. Mucosal closure is final and most critical step of poem procedure after myotomy. Close approximation of the mucosal edges is of utmost importance for healing by rapid epithelialization of the mucosal incision site. At times the mucosal edges are known to get inverted during the closure leading to prolonged healing due to delayed or failed epithelialization. Hence every precaution should be taken to avoid inversion of the mucosal edges during the closure. We describe buried mucosal incision site as a rarely reported complication of poem procedure. A 33-year-old female presented with chief complaint of dysphagia to liquids, mordant solids, nasal regurgitation, intermittent chest pain, and weight loss since 3 years. Her record score was 5. There were no comorbidities. She was evaluated with aperitif endoscopy, barium swallow, and esophageal manometry and was diagnosed with primary achillesia cardia. After detailed counseling about treatment options, she was planned for peroral endoscopic myotomy. Seizure was uneventful, except for mild bleeding during myotomy, which was handled appropriately. However, difficulty was noted during mucosal incision side closure, both in the proximal and distal part of the incision. On the proximal side of the incision, due to redundant mucosal folds, the approximation was difficult. However, it was accomplished with repeated manoeuvres. In the distal part of the incision, the mucosal incision site was getting buried, as the right side of the mucosal edge could not be closely approximated, in spite of repeated good attempts. All the haemoclips causing the burial of the incision were removed with the rat tooth forceps. The closure was done again using wide angle clips and good endoscopic suction. The final closure of the mucosal incision site looked quite secure and the patient was monitored closely during the post-operative period. On day 2, patient had persistent tachycardia and a fever spike. On day 3, tachycardia continued. Biochemistry showed leukocytosis and increased CRP. CT chest showed fluid collection in the submucosal tunnel with fewer foci. However, there was no medicinal collection. The patient was subjected to repeat endoscopy. On initial assessment, the clips looked secure in place with well-approximated mucosal edges. However, on closer examination, it showed buried mucosal incision site on the oral side of the incision with potential space between the approximated mucosa and the mucosal incision as highlighted here, with some purulent collection extruding. This probably led to fluid collection in the submucosal space with secondary infection. We first removed few clips on the oral side. However, due to thick purulent collection, we subsequently removed all the clips using a rat tooth forceps. The submucosal tunnel was examined closely, which showed frank pus collection inside. The entire collection was sucked out and thorosaline lavage was given. No breach was seen on the muscle side of the tunnel. As the cavity was non-dependent, we decided to widen the mucosal incision to allow the pus to drain out freely in the lumen as further collection could lead to fatal mediastinal leak. Lastly, an NJ tube was placed for internal nutrition. Check endoscopy on day 7 showed significant progress in healing of esophageal mucosa with no pus collection. Patient was discharged and rest of the recovery was uneventful. Secure closure of the mucosa is most crucial step in POEM procedure. Any breach in the mucosal closure can lead to disastrous complication like tunnel infection secondary to fluid collection in the potential dead space within the submucosa which may result in mediastinitis. Buried mucosal incision site is a rare poorly recognized complication of POEM procedure. It occurs due to improper approximation of the mucosal edges which leaves a potential space between the approximated mucosa and the mucosal incision site allowing fluid seepage within the submucosal tunnel. Whenever in doubt, the patient should be closely monitored clinically and radiologically for early recognition and timely management.

POEM procedure

buried mucosal incision site

complications

closure difficulties

infection