Clinical and morphological features of allergic enterocolitis in young children

Abstract

The purpose was to study the clinical and morphological features of allergic enterocolitis in young children.Material and methods. 29 patients aged from 2 months to 2 years with severe allergic enterocolitis, who underwent endoscopic examination with targeted biopsy of the intestinal mucosa, were treated. For comparison of morphological, histochemical and immunohistochemical features, intestinal mucosal biopsies of children of the same age with gastrointestinal disorders, caused by protracted or chronic course of non-specific non-ulcer process in the intestine, were used. Immunohistochemical studies were performed on serial paraffin sections in accordance with standard protocols using Ab68 (Macrophage Marker) Ab-3 (Clone KP1), IgA (Heavy Chain) Ab-2, IgE (Epsilon-Heavy Chain) Ab-1 monoclonal antibodies and Imaging Ultra Vision Quanto Detection System HRP DAB (USA).Results. The debut of gastrointestinal symptoms in young children with allergic enterocolitis was observed in the first months of life and was characterized by vomiting or persistent regurgitations, intense griping, diarrhea with large amounts of mucus and/or blood, and delayed physical development. Presence of inflammatory process of intestinal mucosa with eosinophilic infiltration was morphologically established. According to immunohistochemical study, expression of CD68-macrophages and increased expression of IgA and IgE in the duodenal mucosa were detected.Conclusions. The diagnosis of allergic enterocolitis at an early age is complicated by the absence of specific clinical gastrointestinal symptoms and non-informative allergic examination (IgE-independent mechanism of inflammation), which may require morphological study to verify the diagnosis. Morphologically, in the examined patients, not only the presence of inflammatory process of the mucous membrane of the intestine with expressed eosinophilic infiltration is established, but also the immunohistochemistry data revealed the increased expression of CD68-macrophages, IgA and IgE in the mucous membrane of the duodenum, indicating the activation of both cellular and local humoral immunity.