Biological aspects of appendix pathology: irregular distribution of myenteric ganglia in human appendiceal wall

Although appendicitis is a common disease, basic questions about risk factors and its etiology remain unexplained.

An obstruction of the appendix lumen is usually considered to be the main cause of acute appendicitis. However, more studies are currently dealing with neuroimmune appendicitis.

We studied samples of human appendices with the histological diagnosis of chronic appendicitis. Fixed cryosections of appendiceal walls were examined by immunofluorescence methods using neuronal anti-neurofilament antibody markers and beta III tubulin.

The immunostaining revealed an irregular distribution of myenteric ganglia in inflamed appendiceal walls and unexpected groups of large ganglia unequally distributed in the subserosal area. The comparative analysis of normal and inflamed appendix samples showed differences in the occurrence of myenteric ganglia in the subserosal area. They appeared more frequently on cryosections prepared from the inflamed appendiceal wall.

We propose that the high variability and irregular location of myenteric ganglia in the appendiceal wall are due to an alteration in the motility which results in flaccid appendix emptying. In addition, superficially located myenteric ganglia are exposed to abdominal irritation and may explain the chronic abdominal pain which is often considered to be a sign of chronic appendicitis (Fig. 2, Ref. 23).