Table Small-Bowel Mucosal Histology in Certain Malabsorptive Disorders Disorder Histologic Characteristics Normal Fingerlike villi with a villous: crypt ratio of about 4: 1 Columnar epithelial cells with numerous regular microvilli (brush border) Mild round cell infiltration in the lamina propria Celiac disease (untreated) Virtual absence of villi and elongated crypts Increased intraepithelial lymphocytes and round cells (especially plasma cells) in the lamina propria Cuboidal epithelial cells with scanty, irregular microvilli Intestinal lymphangiectasia Dilation and ectasia of the intramucosal lymphatics Tropical sprue Range from minimal changes in villous height and moderate epithelial cell damage to virtual absence of villi and elongated crypts with lymphocyte infiltration in the lamina propria Whipple disease Lamina propria densely infiltrated with periodic acid-Schiff-positive macrophages Villous structure possibly obliterated in severe lesions Small-bowel x-rays (eg, small-bowel follow-through, enteroclysis, CT enterography, magnetic resonance enterography) can detect anatomic conditions that predispose to bacterial overgrowth.