Allergic proctocolitis

    • patchy edema and erythema

    • nodular lymphoid hyperplasia

    • sigmoid colon, rectum and descending colon



    Lesion: Multiple lymphoid follicles with rim of erythema: the “halo” sign and edema of the sigmoid colon.

    Lesion: Lymphonodular hyperplasia with circumscribed erythema (arrow) and tiny bleeding spot (double arrow) in the descending colon in a breast-fed infant with allergic colitis.


    •4 biopsies from the sigmoid colon.

    •Eosinophils were counted in 10 high-power fields (HPF) and the average number of cells was recorded.

    •≥ 6/HPF.