Eosinophil Counts in Mucosal Biopsies of the Ileum and Colon: Interobserver Variance Affects Diagnostic Accuracy

Box 2

Instructions for participating pathologists. These instructions follow known procedures in identifying and counting eosinophils in human mucosa [10, 12, 13, 21, 22].

Intructions for Examination:

 (i) The aim of this study is to count the maximum number of eosinophils per

   HPF in the ileal, colonic, and rectal mucosa.

  (ii) To do this, identify the 5 HPF with the highest number of eosinophils in

   every slide, then count the eosinophils in each!

  (iii) HPF must be located > 4 crypts from the next lymph follicle.

  (iv) Do not count intravascular and / or degranulated eosinophils.

  (v) Do count mucosal esoinophils that can clearly be identified by their

   granula, even if their nucleus is out of focus or out of the cutting plane.