HISTOLOGICAL STRUCTURE OF THE COLON WALL WITH LENGTHENING AND ITS FIXATION DISORDER IN CHILDREN

SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 80 HISTOLOGICAL STRUCTURE OF THE COLON WALL WITH LENGTHENING AND ITS FIXATION DISORDER IN CHILDREN Zh.B. Sattarov1, M.Sh. Boboev2 Tashkent State Medical University (TSMU)1,2 https://doi.org/10.5281/zenodo.17451711 Abstract. This study presents a morphological analysis of resected colon sections in 26 children undergoing surgery for colon elongation and fixation anomalies with clinical manifestations of chronic colon stasis. Seven patients (27.0%) were diagnosed with a subcompensated form of the disease, while 19 (73.0%) were diagnosed with a decompensated form. Histological examination revealed pronounced structural changes in all layers of the intestinal wall, especially in the mucosa and vascular bed. The most significant morphological signs are microcirculation disorders, the formation of multiple microthrombi, destruction of the epithelial lining, thickening of the muscle layers and inflammatory infiltration. These changes are especially pronounced in decompensated forms of pathology and confirm the limited possibilities of conservative therapy, justifying the need for timely surgical intervention. Key words: children, colon elongation, fixation disorder, chronic colostasis, histological examination, microvascular changes. Introduction According to American researchers, constipation is diagnosed in 30–50% of the workingage population in developed countries and in 5–20% of children in the general population [1,3]. According to Borowitz S.M. et al. (2005), constipation accounts for 3–5% of visits to pediatric outpatient clinics and up to 35% of consultations with pediatric gastroenterologists. Encopresis is detected in 35% of girls and 55% of boys suffering from chronic constipation [7,10]. Despite the high prevalence of chronic constipation (CC), the literature lacks a unified approach to surgical indications for elongation and fixation anomalies of the colon in children. According to several authors, the ineffectiveness of conservative therapy in this pathology reaches up to 60% [4–5]. The histostructural characteristics of the colon in cases of its anomalies in the pediatric population remain insufficiently studied, and the available data are often contradictory. Meanwhile, knowledge of the morphological features of various parts of the colon under pathological conditions is an important prerequisite for selecting adequate surgical tactics [8–9]. Anatomically, the wall of the large intestine consists of four layers: the mucosa, submucosa, muscular, and serous layers [10]. The mucosa includes three components: the epithelium, the lamina propria, and the muscularis mucosae. The epithelium is represented by columnar cells with a brush border and goblet cells that synthesize mucus. Stem cells, endocrine cells, and Paneth cells are also found within the crypts [8,10]. The lamina propria contains various immune system cells, collagen fibers, blood and lymphatic capillaries, as well as nerve elements. The submucosa consists of connective tissue containing the Meissner’s nerve plexus. The muscular layer includes circular and longitudinal layers, between which the Auerbach’s (myenteric) plexus is located. The serous membrane consists of loose connective tissue covered by mesothelium [2]. At present, the morphological SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 81 characteristics of different parts of the colon in its congenital or acquired anomalies in children are insufficiently explored. This has determined the necessity of conducting morphological studies presented in this section of the work [3,6–7]. Objective of the study. To investigate the morphological changes in resected fragments of the colon in children with subcompensated and decompensated forms of its elongation and fixation disorders, and to assess the dependence of the revealed changes on the degree of compensation and the presence of complications (colostasis, encopresis, pain syndrome). Materials and Methods. At the clinical bases of the Department of Pediatric Surgery of Tashkent State Medical University (TSMU), 731 children were examined and treated after being admitted with suspected intestinal obstruction, recurrent abdominal pain, vomiting syndrome, and/or chronic colostasis. Among the total number of patients, elongation of the colon was diagnosed in 648 children (88.6%), and fixation anomalies of the colon were identified in 83 patients (11.4%). The age of the examined patients ranged from 3 months to 18 years. Boys predominated — 440 (60.1%), while girls accounted for 291 (39.9%). Morphological studies were performed in 26 patients who underwent surgical treatment. Among them, 7 patients (27.0%) had a subcompensated form of the disease, and 19 (73.0%) — a decompensated form. All children (100%) were diagnosed with colostasis; in 4 (15.4%) cases, colostasis was combined with encopresis, and in 9 (34.6%) — with pain syndrome. The indications for surgical intervention included: the absence of effect from complex conservative therapy, persistent abdominal pain syndrome, and refractory chronic constipation. The material for morphological analysis consisted of resected fragments of the colon and sigmoid colon obtained intraoperatively. Samples of the intestinal wall measuring 0.5 × 0.5 cm were fixed for 24 hours in 10–12% neutral formalin (pH 7.2–7.4) prepared with phosphate buffer according to Lillie. Paraffin sections with a thickness of 5–6 μm were stained with hematoxylin and eosin. Microscopic examination and photodocumentation were performed using a light microscope “AXIOSKOP-40” (Carl Zeiss, Germany) equipped with a digital camera ProgRes Capture Pro 2.6 connected to a computer based on Pentium IV. Results and Discussion. Light-optical examination showed that the mucous membrane of the colon had a typical structure and consisted of tubular crypts lined by a single-layered columnar epithelium. On the luminal surface, absorptive brush-border cells predominated, whereas in the crypts, the main cellular component was represented by goblet cells (Fig. 1). The lamina propria of the mucosa contained a moderate number of connective tissue cells. The muscular layer of the mucosa (muscularis mucosae) was thin and composed of 3–4 layers of smooth muscle cells. The submucosa was formed by connective tissue similar in structure to the lamina propria. It mainly contained blood and lymphatic capillaries as well as connective tissue fibers. Cellular elements were represented in small numbers (see Fig. 1). At the border between the submucosa and the muscular layer, a predominance of irregularly oriented connective tissue fibers was observed. Adjacent to the submucosa was a circular layer of smooth muscle fibers, which is part of the muscular layer, the distinctive feature of which is the presence of the submucosal nerve plexus (Meissner’s plexus). The muscular layer consists of an inner circular and an outer longitudinal layer. Between them are located numerous large Auerbach’s plexuses, which exceed the Meissner’s plexuses in size and occur much more frequently. At the base of the crypts, cells with intensely basophilic cytoplasm predominate. The columnar cells on the luminal surface of the epithelium are reduced in size, and the surface itself appears slightly swollen (see Fig. 1). In the lamina propria, lymphoid SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 82 infiltrates with the formation of follicle-like structures are revealed. In several cases, the muscle fibers of the muscular layer do not exhibit clear stratification into circular and longitudinal layers but are arranged in a chaotic manner. Fig. 1. The connective tissue framework formed by collagen and other types of connective tissue fibers interlacing with each other and creating a felt-like structure. H&E. ×10×10. The connective tissue framework of the muscular layer is mainly formed by collagen and other types of fibers of various diameters, which interweave with each other, forming a felt-like structure. The lumina of most microvessels are plethoric, and in some of them, microthrombi are visualized. Lymphatic capillaries have thin walls and dilated lumina; in some cases, a homogeneous eosinophilic substance, presumably of lymphatic origin, is detected within them. In cases of developmental anomalies of the large intestine, the mucous membrane undergoes pronounced morphological changes. In the subcompensated stage, shortening and tortuosity of the crypts are observed, as well as a disruption of the ratio between goblet and columnar cells toward the predominance of the former. Degenerative changes of the epithelial lining are clearly expressed, especially on the luminal surface (Fig. 2). Fig. 2. Disruption of the integrity of the superficial epithelial layers of the colon in its developmental anomaly. Subcompensated stage. H&E. ×10×10. Fig. 3. Marked hypertrophy of the nerve endings in the wall of the colon. Subcompensated stage. H&E. ×10×40. Pronounced inflammatory infiltration of the epithelium is observed, extending to both its superficial and deep layers (see Fig. 2). At the level of the crypt bases, accumulations of lymphoid SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 83 cells organized in the form of Peyer’s patch–like structures are formed. The muscular layer, as well as the muscularis mucosae, are characterized by marked thickening. Within the thickness of the muscular layer, numerous Auerbach’s nerve plexuses are visualized (Fig. 3), whose number and size are significantly increased. Significant pathological changes were also revealed in microvessels of various calibers. These vascular disturbances involve all layers of the colonic wall — from the epithelial lining to the serous membrane (Fig. 4). Fig. 4. Congestion of the blood vessels in the wall of the colon and edema of the submucosal layer. Subcompensated stage. H&E. ×10×40. A characteristic feature is the formation of both parietal and occlusive (intraluminal) microthrombi. The vascular alterations are accompanied by pronounced edema in the surrounding connective tissue (see Fig. 4), which indicates impaired tissue trophism and local microcirculation. The conducted morphological studies demonstrated that in decompensated forms of the disease, the changes in all layers of the colonic wall are more pronounced. The most significant lesions were identified in the epithelial lining: deep destructive processes, mainly in the luminal zone, disruption of epithelial integrity, marked inflammatory infiltration of the mucosa, and generalized edema of all layers of the intestinal wall were observed. These changes were accompanied by thickening of both the muscularis mucosae and the muscular layer as a whole. In addition, significant alterations were observed in the microcirculatory bed: venous stasis, dilation of vascular lumina, and the presence of multiple microthrombi. These morphological signs indicate pronounced tissue ischemia and impaired tissue perfusion, accompanied by interstitial edema in all layers of the intestine (Fig. 5). Fig. 5. Congestion of the blood vessels in the wall of the colon and formation of thrombi. Decompensated stage. H&E. ×10×40. DS. The most severe destructive and inflammatory changes are recorded in the decompensated forms of the disease. Of particular note are the microcirculatory disorders represented by stasis, SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 84 microthrombosis, and edema, which probably constitute one of the key pathogenetic bases of clinical manifestations such as pain syndrome, colostasis, and encopresis. Conclusion The histomorphological studies of the colonic wall in children with elongation and fixation disorders made it possible to establish that the pathological process affects all structural components of the intestinal wall — from the mucosa to the serosa — with the most pronounced changes observed in decompensated forms of the disease. 1. Changes in the mucosa. In the mucosa, during subcompensated and especially decompensated stages of elongation and fixation anomalies of the colon, pronounced architectural disturbances were identified: shortening and tortuosity of the Lieberkühn crypts, disruption of their parallel orientation; alteration of the cellular composition of the epithelium with a shift in the ratio between goblet and columnar cells toward an increase in the former, which probably has a compensatory character aimed at enhancing mucus production; areas of epithelial destruction and desquamation were noted, along with disruption of the integrity of the superficial epithelium, especially at the tips of folds and crypts. The lamina propria of the mucosa showed marked inflammatory infiltration consisting of lymphocytes, plasma cells, and macrophages; in some cases, accumulations of lymphoid tissue forming structures analogous to Peyer’s patches were observed. 2. Changes in the muscularis mucosae and muscular layer. The muscular layer of the mucosa was thickened, showing signs of compaction and connective tissue proliferation. The muscular coat (tunica muscularis) lost its distinct stratified structure: circular and longitudinal fibers were arranged chaotically, violating the typical topography. In the intermuscular spaces, elements of fibrosis and focal inflammatory infiltration were revealed. The Auerbach’s nerve plexuses (plexus myentericus) were enlarged and hypertrophied, which may indicate their reactive state against the background of chronic motility disturbances. 3. Vascular changes. Significant pathological alterations were found in the microcirculatory vessels of all layers of the colonic wall: signs of vascular stasis, dilation of capillary lumina, and increased permeability of vascular walls. Microthrombi of both parietal and occlusive types were detected in venules and capillaries. These vascular changes were accompanied by pronounced connective tissue edema, particularly in the submucosal and serous layers, indicating ischemic and congestive processes leading to tissue hypoxia. 4. Clinicomorphological correlation. The severity of histomorphological changes directly correlates with the stage of the disease: during decompensation they reach a maximum, while during subcompensation they remain less pronounced but already noticeable. Morphologically confirmed alterations in the epithelial, muscular, and vascular components of the intestinal wall serve as the structural substrate of clinical manifestations — chronic colostasis, encopresis, and pain syndrome. Impaired neural regulation (hypertrophy of the nerve plexuses) and microcirculation confirm the pathogenetic nature of peristaltic and intestinal transport disorders. 5. Practical significance. The detected morphological changes in the wall of the colon during subcompensated and decompensated stages of elongation and fixation anomalies indicate the progressive nature of the pathology. The obtained data suggest the insufficient effectiveness of conservative therapy at these stages of the disease. SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 10 OCTOBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 85 Thus, the morphological signs of decompensation can serve as a basis for the timely selection of surgical treatment in children with this pathology, aimed at preventing further irreversible changes in the intestinal wall and improving the clinical prognosis. REFERENCES 1. Javadov E.A., Kurbonov F.S. Diagnostic criteria for selecting the treatment tactics of chronic colostasis in patients with dolichocolon. Annals of Surgery: Scientific and Practical Journal. Moscow: Meditsina; 2011;(1):53–55. 2. Komissarov M.I. Diagnosis and treatment of chronic constipation in children. Abstract of PhD Dissertation (Candidate of Medical Sciences). Saint Petersburg; 2009. 18 p. 3. Sattarov J.B., Tillaboev S.V. Selection of treatment tactics and methods of surgical correction in anomalies of fixation and elongation of the colon in children. Journal “New Day in Medicine.” 2017; 9(20):588–594. 4. Sattarov J.B., Tillaboev S.V. Immediate and long-term results of conservative and surgical treatment of children with anomalies of fixation and elongation of the colon. Eurasian Journal of Pediatrics. Tashkent; 2022; 1(4):10–14. 5. Khavkin A.I. Chronic constipation: approach to therapy. Russian Medical Journal. 2006;(3):3–6. 6. Khamraev A.J., Karimov I.M., Mirzakhmedov U.M. Surgical treatment of children with chronic colostasis. Surgery of Uzbekistan. 2018;(4):24–30. 7. Ergashev N.Sh., Tillaboev S.V., Sattarov J.B., Baybekov I.M. Morphistological changes in the wall of the colon with elongation and impairment of its fixation in children. Annals of R.S.C.B. 2021; 25(1):356–366. Available at: http://annalsofrscb.ro 8. Johnson M.R., Smith K.L., Brown A.C. Enteric nervous system abnormalities in pediatric dolichosigma: histological analysis. Journal of Pediatric Gastroenterology and Nutrition. 2024; 78:112–119. 9. Ross M.H., Rommel L.J., Kaye G.I. Histology: A Text and Atlas. Digestive System. 4th ed. 2020; Vol. 1:404–495. 10. Volkov A.I., Sidorova O.P. Morphofunctional changes in the muscular layer of the sigmoid colon in childhood dolichosigma. Children’s Surgery. 2023; (–):34–40.