Congenital abnormalities and anatomical variations of the vermiform appendix and mesoappendix

Abstract Aim The purpose of this review was to present and discuss the anatomical variations and congenital abnormalities of the vermiform appendix and mesoappendix reported in recent years, and their associations with acute appendicitis and other associated pathologies. Methods The search was carried out in the following databases: PubMed, Science Direct, and SciELO. Results Thirty-seven studies were included in this review. Among the abnormalities of the vermiform appendix identified are agenesis and duplicity, and anatomical variations were related to length and positioning. Appendicular duplicity was a more frequent abnormality, mainly Type B2, associated with acute appendicitis, followed by agenesis, Type III. The first case of agenesis associated with acute appendicitis and volvulus-type duplicity of the appendix was identified. The most frequent position was retrocecal in adults and pelvic in children. In the mesoappendix, anatomical variations in its positioning, shape, absence, and length were identified. Conclusion This review sought to present and discuss the anatomical variations and congenital abnormalities of the vermiform appendix and mesoappendix reported in recent years, and their associations with acute appendicitis and other associated pathologies, contributing to aid in clinical diagnosis and surgical interventions in patients with suspected acute appendicitis.