Post-polypectomy ileocolic intussusception: A Case Report of a rare adult complication following colonoscopy

Abstract

Introduction

Adult intussusception is rare, and its occurrence following colonoscopy—especially after multiple polypectomies—is exceptionally uncommon. This case highlights a rare post-endoscopic complication with implications for early diagnosis and management.

Case presentation

A 55-year-old man presented with abdominal pain, bloating, and nausea 24 h after colonoscopy with removal of nine polyps via cold snare technique. CT revealed ileocolic intussusception without a clear lead point. Conservative management failed. Exploratory laparotomy revealed an inflamed bowel segment at the polypectomy site. A right hemicolectomy with ileocolic anastomosis was performed.

Discussion

Histopathology showed mucosal ulceration, mural abscesses, and submucosal oedema without malignancy—supporting inflammation as a transient lead point. Despite SLE and multiple comorbidities, early surgical intervention resulted in full recovery.

Conclusion

This case emphasises vigilant monitoring of high-risk patients post-polypectomy and the need to include intussusception in differential diagnoses of acute abdomen following colonoscopy.

Highlights

• •Rare post-colonoscopy ileocolic intussusception in a 55-year-old male
• •Symptoms developed within 24 h following routine polypectomy.
• •CT confirmed intussusception; no lead point was identified.
• •Surgical resection undertaken due to concerns of bowel ischaemia
• •Histology revealed inflammation, no malignancy; patient made full recovery.

1. Introduction

Intussusception, the telescoping of a bowel segment into an adjacent lumen, is rare in adults, accounting for 1–5 % of mechanical bowel obstructions [1]. Unlike paediatric cases, adult intussusception often has a pathological lead point, such as malignancy (77 % of cases), polyps, or inflammatory lesions [2]. Post-colonoscopy intussusception is exceedingly uncommon, with only a few cases reported globally. Intussusception following colonoscopy may arise either due to the procedure itself or as a consequence of an additional intervention, such as polypectomy, carried out during the examination [3]. This case highlights the importance of recognising this complication in elderly patients after colonoscopy, particularly those with polypectomy. This case report has been reported in line with the Surgical Case Report (SCARE) 2025 criteria [4].

2. Case presentation

A 55-year-old male with a medical history of chronic obstructive pulmonary disease (COPD), multiple deep vein thromboses/pulmonary emboli (DVT/PE), systemic lupus erythematosus (SLE), osteoarthritis, and carpal tunnel syndrome presented to the Emergency Department (ED) with acute abdominal pain, bloating, and nausea 24 h after a routine screening colonoscopy. During the procedure, nine polyps had been excised, including a 6 mm tubulovillous adenoma with low-grade dysplasia in the descending colon and hyperplastic or sessile serrated polyps in other segments. All polyps were removed using the cold snare polypectomy technique, and none required cautery. The patient had no personal or family history suggestive of polyposis syndromes, and no genetic testing was indicated.

On examination, his vital signs were stable (blood pressure 132/80 mmHg, heart rate 86 bpm, temperature 37.2 °C), but abdominal examination revealed mild distension, right lower quadrant tenderness, hypoactive bowel sounds, and guarding without rebound tenderness. Investigations demonstrated leucocytosis (white blood cell count 12,000/mm³) and elevated C-reactive protein (83.5 mg/L), with normal lactate (0.7 mmol/L). Following consultant advice, computed tomography (CT) of the abdomen and pelvis was done that confirmed ileocolic intussusception extending to the mid-transverse colon, with faecal material in the distal ileum but no small bowel dilatation or definitive lead point (Fig. 1). The presence of faecal material in the distal ileum without small bowel dilatation suggests partial obstruction or altered peristalsis, which may have contributed to intussusception. Initial management included nil by mouth status, intravenous fluids, nasogastric decompression, and broad-spectrum antibiotics (ceftriaxone and metronidazole). Due to persistent symptoms and concerns for bowel ischaemia, an exploratory laparotomy was performed, revealing telescoping of the ileum into the caecum up to the hepatic flexure. A right hemicolectomy with terminal ileum resection and ileocolic anastomosis was subsequently carried out.

Fig. 1.

CT scan abdomen showing ileocolic intussusception in both coronal and axial view.

Macroscopic examination of the resected specimen confirmed intussusception, while histopathology revealed mucosal ulceration, mural abscess formation, submucosal oedema, and acute inflammation, with no evidence of malignancy or dysplasia.

The patient recovered uneventfully and was discharged on postoperative day seven. At discharge, the patient was able to feed orally and was passing stools normally. During follow-up visits, the patient had no complaints. A surveillance colonoscopy six months later showed no recurrence of polyps or intussusception.

3. Discussion

Complications following colonoscopy are uncommon, with reported global rates of perforation, post-procedural bleeding, and mortality at 0.05 %, 0.26 %, and 0.0029 %, respectively [5]. It is important to distinguish between diagnostic and operative colonoscopies: the former focuses on identifying abnormalities, while the latter involves therapeutic interventions such as polypectomy or haemostasis. Operative procedures carry a higher risk of complications, including bleeding, perforation, and intussusception, some of which arise directly from tissue resections, while others have less well-understood mechanisms [6].

Several mechanisms have been proposed for post-polypectomy intussusception, including local mucosal oedema [7], transmural thermal injury from coagulation [3], and transient motility disturbances [1]. In our patient, histopathological findings of mural abscesses and submucosal oedema support the theory of inflammation-driven intussusception rather than a fixed lead point. We believe a combination of mechanical bowel manipulation, bowel wall inflammation, and peristaltic disruption post-polypectomy contributed to the telescoping of the ileum. Unlike other reports, this patient exhibited no malignancies but had multiple polyps, suggesting mechanical factors such as polypectomy-induced mucosal oedema contributed to telescoping.

This case is consistent with previous reports of post-colonoscopy intussusception, which predominantly affects individuals over the age of 45 [6]. Males are more frequently affected in reported cases, with one review suggesting a male-to-female ratio of approximately 5:2 [7], though this is based on limited case reports and should be interpreted cautiously. Notably, almost all cases of post-colonoscopy intussusception occur on the right side of the colon. Only one instance was an ileocolic intussusception, while the rest were colocolic. In every case, the colonoscopy extended to the right colon [7].

In post-operative colonoscopy, symptoms (abdominal pain, nausea, vomiting and occasionally rectal bleeding) typically manifest within 24 h post-procedure, as seen here, with right-sided involvement (ileocolic or colocolic) likely attributable to ileocaecal manipulation during colonoscopy [7,8]. Key risk factors include polypectomy-induced mechanical traction, terminal ileal intubation, and reduced mesenteric stability associated with low body fat [3]. We believe a combination of mechanical bowel manipulation, bowel wall inflammation, and peristaltic disruption post-polypectomy contributed to the telescoping of the ileum.

Diagnostically, post-colonoscopy intussusception poses challenges due to overlapping symptoms with common complications such as ileus or perforation. Computed tomography (CT) remains pivotal for differentiation, typically revealing classic signs such as the “target sign” or a “sausage-shaped mass” [6,8,9]. In this case, CT confirmed ileocolic intussusception but failed to identify a lead point, highlighting the potential role of inflammation or transient dysmotility as underlying triggers [8]. While no definitive lead point was observed on imaging, histopathology revealed mural abscesses and oedema that may have acted as a transient inflammatory lead point.

Management of intussusception after colonoscopy is not standardised due to its rarity. Generally, adult intussusception warrants resection because of the high risk of an underlying pathology [1]. However, when occurring acutely after a benign colonoscopic procedure, a more conservative approach may initially be justified. In reported cases, initial non-operative management (bowel rest, intravenous fluids, and observation) has been attempted [10]. Endoscopic reduction can also be considered if the patient is stable and there are no signs of peritonitis [11]. When conservative measures fail or if there is evidence of bowel compromise, surgical intervention is indicated. In the largest review, 63 % of patients ultimately required surgical resection [6]. In operative cases, laparoscopic reduction is usually attempted first; resection is performed if the bowel is non-viable or if a pathological lead point is suspected [6,11]. In our case, open surgery was chosen due to concerns about bowel ischaemia and the need for complete inspection and resection. Laparoscopic reduction was not attempted, given the patient's worsening symptoms and intraoperative findings suggestive of non-viable bowel. One author recommends that, if surgery is required, reduction should be attempted before resection once ischaemia has been excluded [11]. The biopsy of the resected tissue, coupled with intraoperative findings of mural abscesses and ischaemia, justified the need for surgical intervention.

After considering the possible mechanisms, it is likely that intussusception in this patient resulted from a combination of patient- and procedure-related factors. The presence of multiple polyps and underlying systemic lupus erythematosus (SLE)—a condition associated with vasculitis and bowel inflammation—may have increased mucosal vulnerability. Scope-related factors, including terminal ileal intubation, air insufflation, and repeated manipulation during multiple polypectomies, could have disrupted normal peristalsis and promoted invagination. Right-sided involvement, as observed in this case, is consistent with the greater mobility of the right colon, relative mesenteric laxity, and the tendency for transient functional paralysis of the ileocaecal region after extensive manipulation. Together, these factors likely triggered inflammation-driven intussusception without a fixed pathological lead point. This underscores the importance of meticulous endoscopic technique, particularly in high-risk patients, to minimise trauma and prevent such rare but serious complications.

4. Conclusion

This case highlights intussusception as a rare but serious complication following colonoscopy with multiple polypectomies. A combination of patient-related factors, including systemic comorbidities, and scope-related factors, such as ileocaecal manipulation and air insufflation, likely contributed to the development of this complication. Early recognition and timely surgical intervention remain key to successful outcomes.

To minimise risk, we recommend: (1) careful selection of patients undergoing multiple polypectomies in a single session; (2) minimising insufflation and avoiding excessive manipulation of the ileocaecal valve; (3) considering staged procedures in patients with high polyp burden; (4) meticulous technique to reduce bowel wall trauma; and (5) structured observation for at least 24 h in high-risk patients, coupled with clear post-procedure instructions regarding early return if abdominal symptoms develop.

Further research and accumulation of case data are needed to better understand the pathophysiology and to refine peri-procedural protocols for prevention and monitoring.

CRediT authorship contribution statement

Study concept or design: Muhammad Ijaz, Umar Mahmood, & Ibtissam Bin Khalid.

Data collection: Muhammad Ijaz & Ibtissam Bin Khalid.

Data analysis or interpretation: Umar Mahmood, Zainab Amir, Fatima Amir Cheema & Nabila Shaukat.

Writing the paper: Umar Mahmood, Zainab Amir, Nabila Shaukat & Fatima Amir Cheema.

Consent

Informed consent was taken from the patient.

Ethical approval

Ethical approval was not required for this case report as per hospital guidelines, as it involves the description of a single clinical case and does not constitute systematic research. Written informed consent for publication of this report, including the use of clinical details and images, was obtained from the patient.

Guarantor

Dr Umar Mahmood MBBS, MRCS (Eng), BSc (Eng).

Post-graduate Resident Paediatric Surgery, The Children’s Hospital and University of Child Health Sciences Lahore Pakistan.

Email: umarmahmud1992@live.com.

Cell #+92-332-4741778.

Declaration of Generative AI and AI-assisted technologies in the writing process

During the preparation of this work, the author used Chat GPT 4.5 to enhance clarity, improve the structure of the writing, and generate suggestions for the presentation of the case report. After using this tool/service, the authors reviewed and edited the content as needed and took full responsibility for the content of the publication.

Source of funding

This research did not receive any specific grant from funding agencies in the public, commercial, or non-profit sectors.

Declaration of competing interest

There is no conflict of interest.