Increased eosinophils in the muscularis propria of appendix may indicate early symptomatic appendicitis
Background: The presence of neutrophils in muscularis propria is known to best correlate with clinical symptoms of acute appendicitis. Eosinophils present in the muscularis propria were noted in cases of acute appendicitis in 2000 (Carr, NJ. Annal of Diagnostic Pathology 2000;4:46–58), but the significance of their presence there has been unclear. The goal of this study was to investigate whether increased eosinophils in muscularis propria could be correlated with early symptoms of patients with clinical diagnosis of symptomatic appendicitis.
Methods: Seventeen patients with clinical diagnosis of acute appendicitis were identified as having acute symptomatology, but the resection specimens displayed a lack or low number of neutrophils (inclusion criteria; neutrophils ttest and P value less than 0.05 was considered to have statistical significance (*).
Result: No neutrophils or eosinophiles were identified in the muscularis propria of normal appendix tissue from colectomy specimens for cancer (n = 10). In symptomatic appendicitis cases (mean age at 17 old years; 15 less than 10 years old and 2 adults), there were higher counts of eosinophils (3.57 ± 0.49), when compared to the number of neutrophils per high power field (0.06 ± 0.06) (P = 0.0001*).
Conclusions: Our findings confirmed the presence of eosinophils in the muscularis propria as observed previously. In addition, our data indicate that eosinophils appeared more sensitive than neutrophils in correlation with early acute clinical symptoms for appendicitis, implying that increased eosinophils in muscularis propria may be a marker for early symptomatic appendicitis.
Zhang PL, Qu Z. Increased eosinophils in the muscularis propria of appendix may indicate early symptomatic appendicitis. Histopathology. 2022 Oct 1; 81(1S):64.