INCIDENTAL DISCOVERY OF COLON PERFORATION BY VENTRICULOPERITONEAL SHUNT MIGRATION REQUIRING SIGMOIDECTOMYJeffrey Baum, MD1; Paige Varney, MD1; Joe Caliendo, BS2; Hsu-Tsai Chi, MD, FACS1; 1Icahn School of Medicine at Mount Sinai Hospital, Mount Sinai South Nassau; 2University of Miami

Background: Ventriculoperitoneal shunts (VPS) are widely used for hydrocephalus but carry risks of infection, malfunction, and catheter tip migration. Among the rarest complications is bowel perforation, reported in 0.01–0.07% of cases, most often involving the sigmoid colon or rectum.[1],[2] If unrecognized, this can result in peritonitis, meningitis, or death.[3] Notably, patients can remain asymptomatic, which complicates a timely diagnosis.

Case Presentation: A 65-year-old male with normal pressure hydrocephalus underwent an uncomplicated VPS placement. Eight weeks later, he presented with right upper quadrant pain and was found to have a localized intra-abdominal abscess at the catheter tip [Figure 1]. He underwent a laparoscopic washout, adhesiolysis and shunt revision, with cultures growing Staphylococcus lugdunensis. After completing six weeks of intravenous antibiotics, a routine follow-up CT scan showed resolution of the abscess but incidentally discovered migration of the distal catheter tip into the sigmoid colon [Figure 2].

Remarkably, the patient remained entirely asymptomatic, with normal bowel function, stable vital signs, and a benign abdominal exam. Given the risk of catastrophic sequelae, urgent exploratory laparotomy was performed and confirmed dense adhesions and intraluminal termination of the shunt in the sigmoid colon [Figures 3 and 4]. Operative interventions included extensive adhesiolysis, two small bowel resections with primary anastomoses, sigmoidectomy with colorectal anastomosis, and a diverting loop ileostomy. The VPS was removed entirely. He recovered well with antibiotics and was discharged home with plans for a staged VPS revision.

Discussion: Colonic perforation by a VPS is exceedingly rare in adults with some reports of a subtle and even silent presentation,[4] with fewer than 25% of patients showing signs of peritonitis.[5] Timely intervention is key for preventing peritonitis and intracranial infection via retrograde bacterial ascension.[6] Proposed mechanisms of VPS migration include catheter tip pressure necrosis combined with risk factors such as fibrous adhesions causing an anchoring effect, and previous intraabdominal infections.[7] Treatment is transection and externalization of the shunt at the neck, surgical retrieval of the intra-abdominal portion and, when indicated, trans-anal extraction of the distal portion via colonoscopy.[8] This case highlights the challenge of asymptomatic presentations, which may only be discovered incidentally on imaging.

Conclusion: VP shunt-related bowel perforation can be entirely asymptomatic yet remains a potentially fatal complication. Clinicians should maintain a high index of suspicion in patients with prior intra-abdominal pathology. Even in the absence of symptoms, prompt imaging, multidisciplinary evaluation, and surgical management are critical to preventing life-threatening outcomes.