Clinical and histopathological response to acitretin therapy in lipoid proteinosis.

Lipoid proteinosis (LP) is a rare autosomal recessive genodermatosis associated with deposition of periodic acid-Shiff (PAS)-positive hyaline material in skin, mucosa, and other tissues. LP is caused by loss-of-function mutations in the extracellular matrix protein 1 gene (ECM1). No curative therapy is available. In this report, we describe the clinicopathological and genetic features of a Turkish LP family with four cases, and evaluate the response of acitretin therapy. Patients were presented with hoarseness and beaded eyelid papules, thickened frenulum, hyperkeratotic plaques and infiltrated warty papules and nodules. Skin biopsies revealed deposition of PAS-positive hyaline material in dermis. A homozygous nonsense mutation in exon 3 of the ECM1 gene, R53X, was detected in the family. Acitretin therapy was administered in two patients, in whom some regression and softening of skin lesions were achieved. However, no histopathological change in PAS-positive deposition could be detected. Although there is no current effective treatment for LP, acitretin may be helpful for patients, especially those who complain about hyperkeratosis.