A diagnostic cascade from cholecystitis to Meckel's diverticulum rupture: a case report.

Background: Meckel's diverticulum (MD) is the most common congenital anomaly of the gastrointestinal tract, yet it rarely becomes symptomatic in adults. Perforation is an uncommon and often overlooked complication that may mimic more frequent abdominal conditions, particularly in the postoperative setting. MD presenting shortly after unrelated laparoscopic surgery is exceptionally rare and can pose a significant diagnostic challenge. Case presentation: A 36-year-old woman presented with acute right upper quadrant pain and was diagnosed with calculous cholecystitis. She underwent laparoscopic cholecystectomy and was discharged after an uncomplicated recovery. On postoperative day 3, she returned with abdominal distension, bilious vomiting, and persistent pain. Imaging revealed a port-site hematoma but no clear source of obstruction or leak. Due to sustained leukocytosis and clinical deterioration, diagnostic laparoscopy was performed, revealing bilious peritonitis and a necrotic, perforated MD with terminal ileal herniation. Diverticulectomy was completed, and the patient recovered fully. Discussion: Perforated MD can closely mimic postoperative ileus, small bowel obstruction, or biliary pathology, leading to delayed diagnosis. Imaging modalities frequently fail to detect this condition, underscoring the limitations of relying solely on radiologic evaluation when symptoms persist. Although a direct causal link to recent laparoscopic surgery cannot be confirmed, postoperative mechanical and perfusion-related changes may contribute to diverticular compromise in susceptible individuals. Conclusion: This case highlights the need to consider MD complications in patients who deteriorate unexpectedly after abdominal surgery. When clinical findings are discordant with imaging, early diagnostic laparoscopy remains essential for accurate diagnosis and timely intervention.