Study to compare the mass cell counts in mucosa and submucosa and muscular layer of the appendix in various histopathological groups

Abstract

Background: Mast cells are immune cells distributed throughout connective tissues, particularly in the gastrointestinal tract, where they play a role in immune regulation and inflammation. Their involvement in appendicitis is not well understood. This study compares mast cell counts in different histopathological groups of appendicitis by evaluating their distribution in the mucosa, submucosa, and muscularis propria.Objectives :To compare mast cell counts in the mucosa, submucosa, and muscular layer of the appendix across various histopathological groups.Methods: This study analyzed100 appendix specimens from patients undergoing appendectomy or laparotomy for suspected appendicitis. Specimens were stained with hematoxylin& eosin (H&E) for histopathological evaluation and Toluidine Blue for mast cell identification. Mast cells were counted in 10 high-power fields (HPF) at 400X magnification, and the mean mast cell count per mm² was calculated. ANOVA was used to assess statistical significance.Results: Among the 100 cases, acute appendicitis was the most common (56%), followed by recurrent appendicitis (32%), acute eosinophilic appendicitis (5%), and normal appendices (7%). Mast cell counts were significantly higher in inflamed appendices compared to normal appendices (p<0.05). The lowest mast cell count was in normal appendices (5 ± 1.9 per mm²), while recurrent appendicitis showed the highest count (16.1 ± 7.7 per mm²). The highest mast cell density was observed in the mucosa of eosinophilic appendicitis (15.5 ± 7.5 per mm²) and in the submucosa (21.4 ± 7.9 per mm²) and muscularis propria (13.9 ± 6.2 per mm²) of recurrent appendicitis. Conclusion: Mast cells are significantly involved in recurrent and eosinophilic appendicitis, particularly in chronic inflammation and fibrosis. Their statistically significant increase in inflamed appendices suggests their potential as diagnostic markers and possible therapeutic targets in recurrent appendicitis.