title: Role of Eosinophils in Acute Appendicitis.
abstract: BACKGROUND
  High negative appendectomy rate still prevails on conventional histologic examination. Increased mural eosinophilic infiltrate had been observed in acute appendicitis. Present study aimed to evaluate the role of mural eosinophils in clinically suspected acute appendicitis but histological normal appendix, as an indicator of acute inflammation, alone or in association with edema and to estimate the cut off value for high eosinophil count for the diagnosis of acute appendicitis.
  
  
  METHODS
  A prospective cross sectional study was conducted on appendectomy specimens which were categorized into three groups of classical acute appendicitis, negative appendectomy and control. HandE and Giemsa stained section were studied for the presence of mural eosinophilic infiltrate, mast cells and edema.
  
  
  RESULTS
  Of total 170 cases, group 1 comprised of 68 cases, group 2 consisted of 78 cases and group 3 consisted of 24 cases. Mean eosinophil and mast cell counts in the muscularis propria were significantly higher in CAA and NA categories when compared to control group. Positive association was found between high eosinophil count and edema in CAA and NA categories. Cut off value of ≥6/ mm2 for mural eosinophil count was not significantly different in between NA and control categories.
  
  
  CONCLUSIONS
  Increased mural eosinophils were significantly present in acute appendicitis and clinically suspected acute appendicitis but histological normal appendix when compared with control group. Sole presence of increased mural eosinophils might represent acute inflammation. However, cut off value for high eosinophil count could not be established to suggest acute appendicitis.
authors.affiliation: Department of Pathology, Nepalese Army Institute of Health Sciences, Kathmandu, Nepal.
authors.forename: R
authors.initials: R
authors.lastname: Shrestha
authors.affiliation: Department of Obstetrics and Gynaecology, Chitwan Medical College Teaching Hospital, Bharatpur, Nepal.
authors.forename: A
authors.initials: A
authors.lastname: Shrestha
authors.affiliation: Department of Pathology, Chitwan Medical College Teaching Hospital, Bharatpur, Chitwan, Nepal.
authors.forename: M
authors.initials: M
authors.lastname: Tiwari
authors.affiliation: Department of Pathology, Chitwan Medical College Teaching Hospital, Bharatpur, Chitwan, Nepal.
authors.forename: S
authors.initials: S
authors.lastname: Ranabhat
authors.affiliation: Department of Pathology, Chitwan Medical College Teaching Hospital, Bharatpur, Chitwan, Nepal.
authors.forename: S
authors.initials: S
authors.lastname: Maharjan
mesh_terms: D000328:Adult; D001062:Appendectomy; D001064:Appendicitis / Q000175:diagnosis* / Q000276:immunology* / Q000601:surgery; D001065:Appendix / Q000276:immunology*; D015415:Biomarkers / Q000378:metabolism; D003430:Cross-Sectional Studies; D004487:Edema / Q000276:immunology; D004804:Eosinophils / Q000276:immunology*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008297:Male; D008407:Mast Cells / Q000276:immunology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers
keywords: acute appendicitis; eosinophil; edema; negative appendectomy.