Familial retrocecal appendicitis.

A family pedigree containing sixteen individuals with acute appendicitis is presented. In all but one the position of the appendix was retrocecal. In two other members explored for abdominal pain wherein acute appendicitis was not the cause, the appendix was also found to be retrocecal. The anatomic retrocecal location of the appendix in this pedigree shows a degree of uniformity that implies a common predisposing factor inherited as a simple, dominant unit-character.