Ultrastructural features of oral discoid lupus erythematosus.

Tissue from buccal and labial mucosal lesions of discoid lupus erythematosus (DLE) was studied in the electron microscope. The material comprised 10 patients, 7 of whom presented skin lesions as well. The epithelium showed a change in differentiation pattern from nonkeratinizing to keratinizing epithelium. Civatte bodies (filamentous bodies) were present intercellularly in the basal and suprabasal cell layers, and in the juxta-epithelial lamina propria. Dyskeratotic cells, suggesting immature stages of Civatte bodies, were recorded in the lower stratae of the epithelium. The epithelium-connective tissue interface was abnormal, presenting detachments, gaps and multiplications of the lamina densa. Cytoplasmic tubular structures were observed in epithelial and endothelial cells, as well as in fibroblasts, lymphocytes and macrophages. The oral tissue changes recorded were common in both groups of patients studied, i.e. with and without skin lesions, and similar to earlier reported changes of DLE skin lesions.