Metallic clip-associated colonic perforation after peroral endoscopic myotomy: A case report

Abstract

BACKGROUND

Colonic perforation secondary to a metallic clip following peroral endoscopic myotomy is exceptionally rare, particularly in patients with achalasia and concomitant chronic constipation.

CASE SUMMARY

We presented a case of a 48-year-old woman with acute abdominal symptoms in which intraoperative exploration revealed a detached metal clip adjacent to the colonic perforation site. A sigmoid colectomy with colostomy was subsequently performed. No discomfort was reported during the 5-month follow-up period.

CONCLUSION

This case highlights vigilance for acute abdominal pain after peroral endoscopic myotomy in chronically constipated patients with possible clip migration.

Key Words: Colonic perforation; Peroral endoscopic myotomy; Achalasia; Chronic constipation; Case report

Core Tip: Colonic perforation potentially related to metallic clip migration after peroral endoscopic myotomy is an unprecedented complication. This case of a 48-year-old woman with achalasia and chronic constipation demonstrates that clip dislodgement may lead to clip-associated acute sigmoid colon perforation, requiring urgent sigmoid colectomy with colostomy. Clinicians should remain vigilant for sudden abdominal pain in post-peroral endoscopic myotomy patients, especially those with chronic constipation, and consider clip-associated injury as a potential etiology.

INTRODUCTION

Colonic perforation, a severe surgical acute abdomen, is associated with a high mortality rate. It is reported to range from 6.2% to 33.3%[1-3]. Patients with colonic perforation typically present with diffuse or localized peritonitis as the primary clinical manifestation. Studies indicate that delayed surgical debridement of infected foci can lead to mortality rates as high as 66% to 72% in patients with diffuse peritonitis[4], primarily due to the delayed onset of abdominal symptoms and signs. Computed tomography (CT) is indispensable in the diagnostic evaluation of colonic perforation, serving as a cornerstone of preoperative assessment by enabling precise localization of the perforation site and facilitating identification of its underlying etiology[5]. Surgery remains the mainstay of treatment.

Achalasia is an esophageal motility disorder characterized by the absence of esophageal peristalsis and inadequate relaxation of the lower esophageal sphincter, primarily caused by degeneration of inhibitory neurons in the myenteric plexus[6]. Among conventional therapeutic approaches, peroral endoscopic myotomy (POEM) has emerged as a leading treatment modality[7]. Notably, while gastrointestinal perforation following POEM has been reported, the majority of cases involve esophageal perforation[8]. Colonic perforation due to migration of metallic clips into the colon after POEM is exceedingly rare, and to the best of our knowledge, no case has been previously reported. Here, we present a case of clip-associated sigmoid colon perforation in a 48-year-old female with chronic constipation following POEM for achalasia, accompanied by a literature review.

CASE PRESENTATION

Chief complaints

A 48-year-old woman presented to the emergency department with sudden-onset severe abdominal pain.

History of present illness

One day prior to admission, the patient had developed lower abdominal pain.

History of past illness

She had a history of chronic constipation but no prior abdominal surgery, inflammatory bowel disease, intestinal tuberculosis, familial intestinal disorders, colonic tumors, or diverticular disease. Twenty-six days before admission, she underwent POEM for achalasia (Figure 1A). Following submucosal tunneling, myotomy, and hemostasis of approximately 20 bleeding points, 8 rotatable and repositionable soft tissue clips (Micro-Tech ROCC-D-26-195; clip diameter 2.6 mm, effective working length 1950 mm) made of medical-grade stainless steel were applied to close the submucosal tunnel entry after confirming the absence of active bleeding, thereby preventing leakage and maintaining mucosal integrity. On postoperative day 3, upper gastrointestinal contrast imaging demonstrated normal esophageal peristalsis without stenosis, a patent cardia, and several metallic clip shadows in the distal esophagus (Figure 1B).

Figure 1 Imaging results. A: Metallic clips were used to close the mucosal layer after peroral endoscopic myotomy surgery; B: Upper gastrointestinal contrast study was performed on postoperative day 3 after peroral endoscopic myotomy, revealing several metallic clip shadows (arrow) in the distal esophagus; C: Abdominal computed tomography scan showed a metal clip was identified adjacent to the perforation site (arrow); D: Coronal computed tomography image clearly depicted the clip (arrow); E: Laparoscopic exploration showed a metal clip was identified adjacent to the perforation site (arrow); F: Resected sigmoid specimen; G: Submucosal abscess with mixed neutrophilic and lymphocytic infiltration (intestinal wall); H: Submucosal abscess with mixed inflammation, necrosis, and focal vascular congestion (intestinal wall); I: Fibroadipose tissue with abscess, mixed inflammation, and focal vascular dilation/hemorrhage (mesentery).

Personal and family history

The patient had no history of substance abuse, consanguineous marriage with parental relatives, or familial genetic disorders.

Physical examination

Physical examination revealed abdominal distension, marked tenderness, rebound tenderness, and muscular rigidity in the lower abdomen.

Laboratory examinations

Laboratory findings included a white blood cell count of 7.69 × 10⁹/L (3.5-9.5), neutrophil ratio of 91.6% (40-75), lymphocyte percentage of 4.8% (20-50), eosinophil percentage of 0% (0.4-8), neutrophil count of 7.04 × 10⁹/L (1.8-6.3), lymphocyte count of 0.37 × 10⁹/L (1.1-3.2), eosinophil count 0 × 10⁹/L (0.02-0.52), and C-reactive protein level of 4.82 mg/L (0-10), with other parameters within normal ranges.

Imaging examinations

Abdominal CT demonstrated a metallic clip adjacent to the sigmoid colon perforation site (Figures 1C and D).

FINAL DIAGNOSIS

Diagnosed as colonic perforation.

TREATMENT

Following cardiopulmonary evaluation, emergency laparoscopic exploration was performed under general anesthesia. Intraoperatively, a metallic clip was identified adjacent to the perforation site, with marked bowel wall edema, impaired perfusion, and gross fecal contamination (Figure 1E). Given the poor bowel viability secondary to impaired perfusion, and the presence of gross fecal contamination, a primary anastomosis was considered unsafe, and a sigmoid colectomy with colostomy was performed (Figure 1F). Histopathological examination of the resected sigmoid colon revealed a focal, full-thickness disruption of the bowel wall, with granulation tissue, necrosis, and inflammatory exudate present at the perforation edges (Figures 1G-I). Marked inflammatory cell infiltration and abscess formation were observed in the adjacent mesentery. A detached metallic clip was identified in the fecal material adjacent to the perforation, without evidence of direct wall penetration, suggesting that localized pressure necrosis was the underlying injury mechanism.

OUTCOME AND FOLLOW-UP

The patient recovered uneventfully and was discharged. No discomfort was reported during the 5-month follow-up period (Table 1).

Table 1 Case timeline.

Time	Event
Day 0	Peroral endoscopic myotomy was performed for achalasia. Eight metallic clips (Micro-Tech ROCC-D-26-195) were placed to close the submucosal tunnel entry
Day 3	Upper gastrointestinal contrast imaging showed normal esophageal peristalsis, a patent cardia, and multiple metallic clip shadows in the distal esophagus
Day 25	The patient developed sudden-onset severe lower abdominal pain
Day 26	Emergency admission. Physical examination revealed lower abdominal distension, tenderness, rebound tenderness, and muscular rigidity. Abdominal computed tomography demonstrated a metallic clip adjacent to a sigmoid colon perforation
Postoperative	Histopathology showed full-thickness bowel wall disruption with granulation tissue, necrosis, and inflammatory exudate at the perforation margins. A free metallic clip was found in the adjacent fecal material, consistent with localized pressure necrosis
5 months after discharge	The patient reported no discomfort and recovered uneventfully

DISCUSSION

Colonic perforation may result from a variety of etiologies, such as colonic neoplasms, diverticulitis, inflammatory bowel disease, colonic ischemia, iatrogenic injury, or foreign body ingestion, necessitating a comprehensive diagnostic approach[9]. Colonic perforation most commonly occurs in the sigmoid colon, primarily linked to the high prevalence of diverticulosis-related complications. In contrast, perforations of the transverse or descending colon are more commonly associated with penetrating trauma or malignant neoplasms, whereas rectal perforations are typically iatrogenic, often resulting from endoscopic procedures[10]. The incidence of colonic perforation displays a bimodal age distribution, with diverticular disease and malignancies predominantly affecting older adults, whereas ulcerative colitis and iatrogenic injuries are more prevalent in younger and middle-aged populations. The male predominance in incidence may be attributed to behavioral risk factors such as smoking and alcohol consumption.

Following colonic perforation, leakage of colonic contents into the peritoneal cavity may result in severe complications such as intra-abdominal abscess, septic shock, and multiorgan dysfunction syndrome, underscoring the critical importance of prompt diagnosis and timely intervention. The typical clinical manifestations of colonic perforation include fever, abdominal pain, localized tenderness, rebound tenderness, abdominal distension, leukocytosis, tachycardia, and hypotension. However, approximately 6% of cases may present with atypical or subclinical symptoms[11]. Laboratory examinations in patients with colonic perforation may demonstrate inflammatory changes; however, systemic inflammatory markers do not always correlate with the severity of intra-abdominal pathology, particularly in localized gastrointestinal perforation. Colonic perforation must be differentiated from other acute abdomen conditions, such as acute appendicitis, acute pancreatitis, and intestinal obstruction. CT imaging is the primary diagnostic modality for gastrointestinal perforation, demonstrating high sensitivity for detecting free abdominal gas[12]. In addition, positive abdominal signs, including abdominal tenderness, rebound pain, and muscle guarding, can reflect the severity and prognosis of the disease to a certain extent, providing important clinical insights for disease assessment and treatment decisions. When a definitive diagnosis can not be reached after all these examinations, a laparoscopic exploration or exploratory laparotomy should be performed immediately. In this case, diagnostic laparoscopy revealed a marked accumulation of fecal material within the colon, with the perforation site localized distal to the sigmoid colon. A metal clip was identified immediately adjacent to the perforation site.

Previous studies have demonstrated that gastrointestinal perforations following POEM for achalasia predominantly occur in the esophagus. The sigmoid colon perforation associated with metal clip dislodgement is exceptionally rare, particularly among patients with chronic constipation. In patients with chronic constipation and delayed colonic transit, stercoral stasis may develop, particularly within the sigmoid colon. A migrated metallic clip may become entrapped within impacted fecal material, leading to sustained localized mechanical compression against the colonic wall. This combined effect of the clip and fecal impaction may impair local mucosal perfusion, resulting in progressive ischemia, pressure necrosis, and eventual perforation. This subacute, pressure-induced mechanism is supported by intraoperative and histopathological findings, which demonstrated marked fecal accumulation without evidence of sharp traumatic injury. Instead, granulation tissue and localized abscess formation at the perforation margins suggested a gradual ischemic and inflammatory process rather than an acute perforation mechanism. Awareness of this rare clip-related mechanism may facilitate earlier recognition of atypical gastrointestinal perforation in patients with achalasia and chronic constipation.

CONCLUSION

This case report describes potentially the first case of sigmoid colon perforation in a patient with achalasia due to ectopic metal clip dislodgement following POEM. Metal clip dislodgement may be a potential etiological factor for occult gastrointestinal perforation in patients with chronic constipation, warranting further case accumulation and experimental studies to clarify the precise pathomechanism and incidence of clip-induced colonic trauma.

ACKNOWLEDGEMENTS

We sincerely thank the patient featured in this case report and especially appreciate the medical staff of the Department of General Surgery at Lanzhou University Second Hospital for their involvement and support in the patient’s diagnosis and treatment.