[Hyalinosis cutis and mucosae. Ultrastructural histochemical aspects indicating intracellular accumulation of glycosaminoglycans].

The exact nature of the genetic defect of hyalinosis cutis et mucosae or d'Urbach-Whiete syndrome is still matter of controversy. The present article reports on three new cases in which several different ultrastructural and biochemical investigations add more arguments to support an anomaly of the glycosaminoglycans degradation in the dermal fibroblasts. Cationic dyes as polyethyleneimine and alcian blue show an intense ultrastructural staining of the abnormal basal laminae and the intracellular lysosomal bodies in cultured fibroblasts. These are related to the accumulation of anionic charged proteoglycans. The primary defect of hyalinosis cutis et mucosae is likely due to a lysosomal defect so far not biochemically defined.