Gluten-sensitive enteropathy: sequence of villous regrowth as viewed by scanning electron microscopy

Small-intestinal biopsy specimens from five children with gluten-sensitive enteropathy (GSE) were studied by scanning electron microscopy (SEM) before dietary treatment and sequentially after removal of gluten from the the diet. Compared with biopsy specimens from patients without evidence of villous atrophy, these specimens showed marked architectural changes. In patients with total villous atrophy observed by light microscopy, absent villi and prominent crypts were observed by SEM. Patients with subtotal villous atrophy had the first stages of villous formation characterized by semicircular ridge formation. Biopsy specimens obtained from the five patients with GSE after dietary treatment demonstrated a sequence of changes characterizing villous repair. The earliest change consisted of semicircular elevations of cells around the crypts. Unequal cellular repletion around the crypts and migration of the cells led to the formation of parallel ridges. Increased cell proliferation resulted in thickening and twisting of the ridges to form convoluted ridges. Increased complexity of the ridges appears to lead to the formation of cerebriform ridges, and septation at various points in the ridges results in the formation of mitten-like villi. In biopsy specimens from patients with villous atrophy from other causes, similar reparative changes were seen by SEM. Scanning electron microscopy is a useful adjunct to the light microscopic and dissecting microscopic assessment of small intestine biopsy specimens, and may be more sensitive tan light microscopy in documenting early morphologic response to dietary treatment for gluten-sensitive enteropathy.