Acute intestinal intussusception revealing Peutz–Jeghers Syndrome in a 16-year-old male: a case report

Introduction and importance: Peutz–Jeghers Syndrome (PJS) is a rare autosomal dominant disorder characterized by hamartomatous polyps throughout the gastrointestinal tract and mucocutaneous pigmentation. Patients are at high risk for complications such as bleeding, obstruction, and especially small-bowel intussusception, which often occurs in childhood or adolescence. Early recognition is essential, as intussusception can be the first life-threatening presentation of PJS. This case highlights the importance of considering PJS in young patients presenting with acute intestinal obstruction. Presentation of case: A 16-year-old male with no medical history presented with 48 hours of diffuse abdominal pain, vomiting, cessation of feces and flatus, and melena. Examination showed generalized abdominal guarding and a palpable left-flank mass. Laboratory tests revealed leukocytosis, elevated CRP, metabolic acidosis, and high lactate. CT scan demonstrated a jejuno-jejunal intussusception with suspected distal ileal intussusceptions. Emergency laparotomy revealed a 2-meter gangrenous jejuno-jejunal intussusception and two additional ileal invaginations caused by polypoid lesions. A segmental small-bowel resection with primary anastomosis and enterotomy for polyp removal was performed. Histology confirmed multiple hamartomatous polyps consistent with PJS. The postoperative course was favorable, and the patient was referred for genetic counseling and surveillance. Clinical discussion: PJS often presents with gastrointestinal polyps that can act as lead points for intussusception. Up to 69% of patients experience at least one episode, particularly in adolescence. Multiple synchronous intussusceptions, as in this case, require thorough intraoperative evaluation of the entire small bowel to identify additional polyps and prevent recurrence. While bowel preservation through reduction and polypectomy is preferred, extensive resection may be necessary when ischemia or necrosis is present. Long-term management includes routine endoscopic surveillance, removal of polyps ≥15 mm, and monitoring for the significantly elevated lifetime risk of gastrointestinal and extra-intestinal malignancies. Genetic counseling is critical for confirming STK11 mutations and informing family screening. Conclusion: This case demonstrates that PJS may initially present as severe, multifocal small-bowel intussusception in adolescents. Prompt diagnosis, surgical management, and comprehensive evaluation for additional polyps are essential to prevent recurrence and complications. Long-term multidisciplinary follow-up is vital due to the high risk of malignancy and recurrence inherent to PJS.