Acute appendicitis is the most common cause of acute abdominal pathology in children. However, other rare non-inflammatory non-neoplastic disorders involving the appendix may manifest as surgical emergencies. This study aimed to describe these atypical entities and present representative cases. The database of a tertiary children's medical center was reviewed for all the patients aged 0-18 years who underwent urgent appendectomy between June 2014 and December 2019, for rare disorders of the appendix unrelated to inflammatory or neoplastic processes. Of 1367 patients who underwent appendectomy, 1345 were operated urgently or emergently. Of these, six, all males, mean age 32.6 months (range 0.7-76), underwent appendectomy for rare surgical complications that involved the appendix. These included torsion of the appendix (2), a strangulated internal hernia through an appendicular ring (1) or through a mesoappendix gap (1), an incarcerated appendix in an acute hernia sac (1), and appendiceal intussusception (1). In all cases, the role of the appendix in the pathologic process was unexpected and came as a surprise to the surgeon. During a median follow-up of 4.2 months (range 1-8 months), one patient underwent relaparotomy for small bowel obstruction 4 weeks after the original procedure.Conclusion: The appendix in children can be the source of rare pathological disorders that present as surgical emergencies. Familiarity with these entities may aid in achieving accurate preoperative diagnosis and contribute to surgical team orientation on exploratory laparotomy. However, correct diagnosis is often only established during timely surgical intervention.
Keywords: Amyand hernia; Appendicular ring; Appendix; Internal hernia; Intussusception; Torsion.