H&E staining of small bowel biopsies from patients II-2 and II-5.

A) Mild villous atrophy associated with a slight increase in number of intraepithelial lymphocytes, and mild chronic inflammation of lamina propria (electron microscopy not shown-normal microvillous architecture); B) the villi appear normal without lymphocytic abnormalities in the intraepithelial and lamina propria compartments. Moreover, very few plasma cells were seen, and the epithelium was devoid of abnormal apoptosis, or abnormalities of microvilli.