Introduction: Twenty to thirty percent appendices removed from patients with suspected appendicitis appear normal on histology. The cause of pain in these patients is unknown. The presence of eosinophils and mast cells should be looked at skeptically which may explain the cause of pain. The aim was to study the eosinophils, mast cells, nerves and ganglions in normal and inflamed appendices.
Materials and methods: A total of 329 appendices including 192 case of acute appendicitis (group A), 94 cases of clinically acute but histologically normal appendices (group B), 13 cases of complementary/elective appendicectomies (group C) and 30 normal controls from medico-legal autopsies(group D), were studied for the presence of eosinophils, mast cells, nerves and ganglia in mucosa, submucosa and muscularis propria. Routine haematoxylin and eosin stained sections were used for eosinophils, nerves and ganglia and Toludine blue sections for mast cell counts. One way ANOVA and logistic regression was used for statistical analysis
Results: The mean eosinophil and mast cell counts were significantly higher in mucosa, submucosa and muscularis propria in Group A and B, when compared to group C+D. The number of nerves and ganglion cells were significantly higher in group A when compared to groups B and C+D. The correlation between eosinophil and mast cell count was not found to be statistically significant.
Conclusion: A significant increase in Eosinophils, mast cells, nerves and ganglion cells was seen in acute appendicitis. Increase in eosinophils and mast cells may explain the pain in histologicaly normal but clinically suspected acute appendicitis.
Keywords: Appendicitis; Eosinophils; Ganglion; Mast cells; Nerves.