Concomitant Meckel's Diverticulum With Focal Paneth Cell Metaplasia and Acute Appendicitis Presenting as Chronic Periumbilical Pain in a Child.

Meckel's diverticulum is the most common congenital anomaly of the gastrointestinal tract but remains diagnostically challenging in children because of its varied and nonspecific clinical presentation. Concomitant Meckel's diverticulum and acute appendicitis are uncommon and may further obscure diagnosis. We report a 9-year-old boy who presented with chronic periumbilical abdominal pain of 3 months' duration, with acute worsening over 3 days accompanied by vomiting. Physical examination revealed localized right periumbilical tenderness without signs of peritonitis. Laboratory investigations demonstrated mild anemia and eosinophilia, while ultrasonography identified an appendicolith with mesenteric lymphadenitis, raising suspicion for appendiceal pathology. Owing to persistent symptoms and concern for evolving subacute intestinal obstruction, diagnostic laparoscopy was performed. Intraoperatively, acute appendicitis was identified along with a dilated Meckel's diverticulum ~100 cm proximal to the ileocecal junction and associated proximal small-bowel dilatation. Laparoscopic-assisted Meckel's diverticulectomy with appendectomy was successfully performed. Histopathologic examination confirmed acute appendicitis with a fecolith and transmural inflammatory infiltrates. The Meckel's diverticulum demonstrated focal Paneth cell metaplasia and lymphoid aggregates consistent with Peyer patches without ectopic gastric or pancreatic tissue or atypia. The mesenteric lymph node showed reactive lymphoid hyperplasia. The postoperative course was uneventful, and the child remained symptom-free at 2-month follow-up. This case highlights the importance of considering dual intraabdominal pathology in children presenting with prolonged or atypical abdominal pain. Diagnostic laparoscopy plays a pivotal role by enabling comprehensive abdominal evaluation and definitive treatment in a single setting. Furthermore, symptomatic Meckel's diverticulum may occur in the absence of heterotopic mucosa, and uncommon histopathologic findings such as focal Paneth cell metaplasia underscore the value of meticulous examination of resected specimens.