Objectives: Cow's milk protein-sensitive enteropathy (CMSE) may persist in children to school age. We sought to define the morphologic and immunohistochemical features of persistent CMSE.
Study design: We studied 15 children with a definite diagnosis of CMSE on the basis of a blind challenge, 12 children with suspected cases of CMSE, 11 children with celiac disease, and 12 control children.
Results: Typical findings in children with CMSE were endoscopically visible lymphonodular hyperplasia of the duodenal bulb and lymphoid follicles without villous atrophy in biopsy samples. The patients with definite CMSE showed significantly increased densities of intraepithelial T cells skewed clearly to gammadelta(+) cells, compared with the control patients but fewer than in the patients with celiac disease. The study children showed no aberrant upregulation of HLA-DR expression in the duodenal mucosa, and the prevalence of HLA DQ2 antigen among them was equal to that in the control children.
Conclusions: Our observations corroborated the claim that CMSE at school age is an identifiable clinical entity. Immunohistochemical findings suggest the abrogation of antigen tolerance locally on the gastrointestinal mucosa. A careful clinical assessment that includes a long elimination-challenge test supported by typical endoscopic and histologic findings form the basis for diagnosis.