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

Abstract

OBJECTIVES: Although appendicitis is a common disease, basic questions about risk factors and its etiology remain unexplained. BACKGROUND: 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. METHODS: We studied samples of human appendices with the histological diagnosis of chronic appendicitis. Fixed cryosections of appendiceal walls were examined by immunofl uorescence methods using neuronal antineurofi lament antibody markers and beta III tubulin. RESULTS: The immunostaining revealed an irregular distribution of myenteric ganglia in infl amed appendiceal walls and unexpected groups of large ganglia unequally distributed in the subserosal area. The comparative analysis of normal and infl amed appendix samples showed differences in the occurrence of myenteric ganglia in the subserosal area. They appeared more frequently on cryosections prepared from the infl amed appendiceal wall. CONCLUSION: 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 fl accid appendix emptying. In addition, superfi cially 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). Text in PDF www.elis.sk.

Subserosal localization of myenteric ganglia in normal human appendix: immunostaining with neuronal and glial markers

“…On the other hand, only several reports with confl icting results are dealing with myenteric ganglia in human appendix. Recently we described the irregular distribution of myenteric ganglia in human appendix (13) and the presence of myenteric ganglia in the subserosal area which occured more frequently in appendices with diagnosis of chronic appendicitis (8). Irregular distribution of myenteric ganglia was described in some studies (14,15).…”

“…However, several studies revealed that the obstruction is not a causative factor of acute appendicitis (6, 7). Recently, we described the atypical myenteric ganglia distribution in relation to appendix pathology (8). Here, we examined the co-expression of neuronal and glial markers in normal human appendiceal wall.…”

Distribution of RET proto‐oncogene variants in children with appendicitis

“…In parallel to HSCR, an altered distribution of intramural ganglia has been found in the appendices of AA patients (Kubikova et al, 2015). Furthermore, up to 50% of HSCR patients are suffering from a recurrent colitis that also persists after resection of the aganglionic colon segment in about half of these patients.…”

“…Recently, genome‐wide association studies (GWAS) found strong association of appendectomies with a SNP near PITX2 (Kristjansson et al, 2017), a gene also involved in intestinal development that has been shown to be significantly less expressed in appendectomy specimen (Orlova et al, 2019). Recent studies also showed an irregular distribution of ganglia in the wall of inflamed appendices, suggesting a possible role of ganglia cell distribution and functioning in the pathogenesis of AP similar to HSCR (Kubikova et al, 2015).…”