Missing Plastic Stent, An Unreported Complication of Endoscopic Retrograde Appendicitis Therapy

Question: A 26-year-old man presented with acute right lower abdominal pain was diagnosed with uncomplicated acute appendicitis after sonogram (Figure A, black arrow) and underwent endoscopic retrograde appendicitis therapy (ERAT). After routine bowel preparation, a colonoscope (GIT-H260; Olympus, Tokyo, Japan) was advanced and appendiceal orifice swelling was observed. A cone-shaped transparent cap was used to push Gerlach’s valve aside, and a zebra guidewire was inserted into the appendiceal lumen, in which the catheter was guided. After injecting contract agent and saline solution, milky pus gushed out and no impacted appendicolith was found. The contrast-enhanced radiograph then showed no filling defect, but a 1.5-cm-long stricture in the proximal of the appendiceal lumen with rough edges (Figure B, black arrow). Therefore, an 8.5F, 5-cm long plastic appendix stent was placed for luminal decompression and stricture dilation.1Liu B.R. Ma X. Feng J. et al.Endoscopic retrograde appendicitis therapy (ERAT): a multicenter retrospective study in China.Surg Endosc. 2015; 29: 905-909Crossref PubMed Scopus (36) Google Scholar The position of the stent was confirmed by colonoscope (Figure C) and radiograph (Figure D, black arrow). The patient was entrusted with a return within 2 months to retrieve the plastic stent. After 2 months, the patient returned to retrieve the stent, claiming no discomfort after the procedure. A regular radiograph scan showed the stent remained in his right lower abdomen (Figure E, black arrow). After the colonoscope was advanced and the Gerlach’s vale pushed aside, the stent could not be observed (Figure F). Where do you infer the stent is? How would you manage this condition? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. After injecting a contrast agent, a radiograph showed that the stent seemed to have migrated into the appendiceal lumen for about 2–3 cm (Figure G, black arrow) and therefore could not be seen. Although the stricture was dilated successfully, the stent no longer connects the appendiceal lumen and cecum, acting as a foreign body instead. Aiming to remove the stent with a stent retriever while preventing it from perforating the appendix, a zebra guidewire to facilitate the retriever was inserted into appendiceal lumen and went through the stent tube under radiographic guidance (Figure H, black arrow). The guidewire was advanced through the stent using the unique flipped-wire or U-wire technique (Figure I, black arrow). The presence of the U-wire, acting as a buffer, provided the stent with adequate support in case the stent migrates deeper into the appendiceal cavity, avoiding complications such as hemorrhage, perforation, or further infection. After that, a stent retriever (Soehendra) was advanced along the guidewire. With the support of the U-curve, after several attempts, the metal retriever was successfully screwed to the proximal of the stent (Figure J, black arrow) and extracted from the appendiceal lumen (Figure K). Then the plastic stent was grasped and retrieved by a rat-tooth forceps from the colon. (The color of the stent has changed because it stayed in the appendiceal lumen for 2 months.) Last, after injecting a contrast agent, a radiograph showed neither perforation nor residue in the appendiceal lumen (Figure L, black arrow). No complications were observed after this procedure. The feasibility and safety of ERAT managing uncomplicated appendicitis is well-established.2BouHaidar D.S. Bawany M.Z. Schubert M.L. ERAT: A new ERA for appendicitis therapy?.Dig Dis Sci. 2016; 61: 3099-3101Crossref PubMed Scopus (5) Google Scholar,3Snyder M.J. Guthrie M. Cagle S. Acute appendicitis: efficient diagnosis and management.Am Fam Physician. 2018; 98: 25-33PubMed Google Scholar Although stent migration out of the appendiceal cavity after ERAT is not uncommon, inward migration remains unreported globally and much more difficult to manage owing to its potential of causing iatrogenic complications like perforation. We report on this world first complication and intend to provide a feasible and safe technique to remove an internally migrated plastic stent. The patient agreed to report on this world first case.