The appendix vermicularis is probably the last human organ with no apparent function. Some aspects of its pathology are equally puzzling, especially so-called “chronic appendicitis” or “obstructive appendicopathy”, in which loose connective tissue replaces the distal lumen, mucosa and submucosa. In extreme instances no lumen is present throughout. Traditionally, although inflammation is minimal or absent, obliteration of the lumen has been attributed to scarring resulting from one or more previous episodes of acute appendicitis.

To obtain insight into this puzzling entity we examined 15 specimens of obstructive appendicitis. The specimens, after fixation in formalin, were cut longitudinally in two pieces. …