Recurrent peritoneal cyst in an adolescent: A case report

Background: Peritoneal cysts are rare intra-abdominal lesions, typically diagnosed in children under the age of 5 years, with an estimated incidence of 1 per 140,000 general hospital admissions. Although histologically benign, they may cause significant morbidity due to their size, anatomical location, and complications such as obstruction, infection, or hemorrhage. Recurrence after aspiration is a well-documented limitation of conservative management.Case Presentation: We report the case of a 15-year-old male who presented with intermittent abdominal pain, vomiting, and altered bowel habits. Imaging revealed a large cystic lesion in the right upper abdomen, adjacent to the liver, gallbladder, and kidney. Ultrasound-guided aspiration removed approximately 550 mL of serosanguineous fluid, but recurrence was noted on follow-up ultrasound within weeks. Patient’s family opted for observation as patient remains asymptomatic at the moment. Discussion: This case highlights the uncommon presentation of a large peritoneal cyst in an adolescent, confirming that this entity should remain a diagnostic consideration for intra-abdominal masses beyond early childhood. The recurrence after aspiration demonstrates the limitation of this approach, reinforcing complete surgical excision as the definitive management strategy to prevent recurrence and reduce morbidity. Although our patient remained asymptomatic post-recurrence under observation, surgical intervention is recommended due to the long-term risk of enlargement and complications.