ABSTRACT
Gingival biopsies were obtained at various intervals for a period of two years from 12 patients suffering from Behçet's disease who were under a clinical trial of cyclosporin A (CsA) treatment. The levels of nondialyzable hydroxyproline (Hypro) were determined in the medium of the cultured tissues. Histologic examinations were also performed every three months. Correlations between the CsA blood levels and the levels of nondialyzable Hypro indicated a reciprocal relationship, especially at blood levels of CsA higher than 600 ng/ml. Histologic examination of gingival sections from CsA-treated patients showed swelling of the epithelial cells, formation of perinuclear clear zones, widening of intercellular gaps and formation of several basal cell layers. In addition, foci of PAS-positive material were found in both the epithelium and stroma. It is assumed that the gingival enlargement observed in the CsA-treated patients was not due to an increase in tissue collagen but rather to an increase in epithelium combined with an accumulation of noncollagenous extracellular matrix material.
