Histological changes in the colon wall in adult patients with chronic slow-transit constipation

The prevalence of chronic constipation in the population ranges from 3% to 27%. Women, senile people, and people of low socio‑economic status are in this risk group more often. Many histological studies of the intestinal wall were performed in order to find the causes of slow‑transit constipation [6, 4]. The different pathological changes, including myopathies, neuropathy, and pathology of the interstitial cells of Cajal, were established. The specific distribution of the types of histological changes in the colon wall in patients with slow‑transit constipation, as presented in the London classification, is currently unknown. Objective — to determine the specific distribution of the types of histological changes in the colon wall in patients with slow‑transit constipation unresponsive to conservative treatment. Materials and methods. A pathomorphological comparative case‑control study was performed. The main group included 105 patients who underwent colectomy as a treatment for chronic slow‑transit constipation in the period 2011—2023. The surgical intervention was indicated for patients with chronic slow‑transit constipation, resistance to conservative treatment, and a notable decline in quality of life. The comparison group included 27 deceased persons who did not experience constipation during their lifetime. The patient exclusion criteria were Hirschsprung’s disease, proctogenic constipation (dysfunction of the rectum and pelvic floor), medication‑associated constipation, as well as mental disorders. The histological and immunological examinations of samples were carried out in both groups, in the comparison group — appendix, ileum, cecum, colon and sigmoid colon. Results. Four main morphological phenotypes of the colon wall structure elements in patients with chronic slow‑transit constipation were identified according to the research data: 1) histologically intact type, 2) myopathic type, 3) Cajal type, 4) neuropathic. A combination of different types of histological changes was also registered, but one of them usually dominated. Conclusions. Four main types of histological changes in the intestinal wall were found in patients with chronic slow‑transit constipation resistant to conservative treatment: myopathic changes (56.2%), Cajal cell pathology (19%), neuropathic changes (19%), and a histologically intact variant (5.8%). The myopathic type is characterised by the heterogeneity of morphological manifestations, which can be referred to as dystrophic changes (dystrophic subtype 79.7%) and inflammatory changes (inflammatory subtype 20.3%), p=0.001.