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Abstract Gastroesophageal reflux disease (GERD) has a global impact on health and quality of life, affecting much of the world’s population. Gastroesophageal reflux disease (GERD) develops when the reflux of gastric contents into the esophagus leads to troublesome symptoms and/or complications and is the most common chronic upper digestive disorder encountered by the gastroenterologist. Typical GERD is defined by the presence of troublesome heartburn with/without regurgitation. Based on endoscopic findings GERD is differentiated in erosive (erosive reflux disease or ERD), non-erosive reflux disease (NERD) and Barrett’s esophagus (BE). ERD is characterized by endoscopic visible breaks of esophageal mucosa integrity and classified according to various endoscopic classifications, most recently the Los Angeles classification. However, two thirds of patients with typical GERD symptoms do not exhibit visible mucosal changes in conventional esophagogastroduodenoscopy (EGD) and are thus diagnosed as having NERD. Frequent histological changes as basal cell hyperplasia, elongation of the papilla, inflammatory infiltrates and dilatation of the intercellular spaces are observed in the distal esophagus of patients with both ERD and NERD. Dilations of the intercellular spaces (ICS) are characteristic changes of the esophageal mucosa of patients with ERD and NERD. ICS were described by various others using electron microscopy and are even characterized by light microscopy. This feature is being more widely proposed as an additional morphological feature of acid induced damage to the squamous epithelium. The widened ICS are supposed to permit the diffusion of molecules to the lamina propria where sensory nerve endings are located Therefore, ICS dilation even in the absence of endoscopically visible Summary and Conclusion 79 mucosal damage may explain the occurrence of symptoms in patients with NERD. The integrity of epithelial surfaces is based on various cell-cell contacts that provide the structural basis for barrier function by regulating the diffusion of molecules and sorting of transmembrane proteins to apical and basolateral surfaces. Tight junctions, adherens junction and desmosomes are the three major structural units mediating barrier and sorting function. At least 19 claudins have been found in the esophageal mucosa, but claudin 1 and 4 are the most prominent. The structure of claudin based tight junctions is yet to be fully resolved, but the primary role of claudins seems to be related to the regulation of paracellular selectivity to small ions. The heterologous expression in monolayers of the majority of claudin isoforms leads to an experimental increase of the transepithelial electrical resistance (TER), predominantly due to a selective decrease in cation permeability. In addition to the more apically orientated tight junction, an intact adherens junction is also required for integrity of the epithelial barrier. The adherens junction performs important roles in cell-cell adhesion and regulation of the actin cytoskeleton. Cadherins, especially E-cadherin, are the major protein components of the adherens junction. They initiate cellular contacts through pairing between cadherins on opposing cells. They can also bind to cytoplasmic proteins (catenins) which locally regulate actin cytoskeleton organization, cadherin stability, and intracellular signaling pathways that control gene transcription. We aimed to study the immunohistochemical expression of Claudin-1 and E-cadherin in patients with gastroesophageal reflux disease Summary and Conclusion 80 Summary of our results: • As regard age and sex, there was an insignificant difference between Erosive and NERD group. • As regard type in erosive group, type A was 11 (52.4%), B was 8 (38.1%), C was 2 (9.5%). • According to Claudin-1, epithelium expression was positive in 11(52.4%) in Erosive group and 9(42.9%) in NERD group. There was no significant difference between both groups as regard epithelium expression, Localization, Pattern, H-Score. Regarding sub epithelium, All cases were negative. • According to E-cadherin, epithelium expression was positive in 17(81.0%) in Erosive group and 19(90.5%) in NERD group. There was no significant difference between both groups as regard epithelium expression, and H-Score. As regard epithelium Localization, the Pattern was significant difference between both groups. Regarding sub epithelium, All cases were negative. • There was no significant relation between Claudin-1 (H-Score) and sex in both groups Erosive and NERD groups. There was no significant relation between Claudin-1 (H-Score) and type in erosive group. • There was an insignificant correlation between Claudin-1 (H-Score) and Age in both Erosive and NERD group. • There was an insignificant relationship between E-cadherin (H-Score) and Sex in both Erosive and NERD group. There was no significant relation between E-cadherin (H-Score) and type in erosive group. • There was an insignificant correlation between E-cadherin (H-Score) and Age in both Erosive and NERD group. |