TOPICAL TREATMENT OF ICHTHYOSES WITH 13-CIS RETINOIC ACID - A CLINICAL AND IMMUNOHISTOCHEMICAL STUDY

In a prospective, double blind, bilateral ly paired comparative study, a cream containing 13-cis-retinoic acid (13-cis-RA) 0.1% and the crea m base only were applied over a period varying between 4 and 10 weeks in 12 ichthyosis patients (1 patient with autosomal dominant ichthyosi s vulgaris (ADIV), 7 patients with X-linked recessive ichthyosis (XRI) 2 patients with bullous congenital ichthyosiform erythroderma of Broc a (BCIE), and 2 patients with erythrodermic lamellar ichthyosis (ELI)) . A significant unilateral improvement was found for the clinical para meters of scaling and induration. Clinical Improvement was observed in all ichthyosis groups, except for ADIV. Continuation of the treatment beyond the first month, caused a further reduction of skin lesions. S ide effects due to the study medication were only minimal and easily c ontrolled by adjusting the application frequency. Biopsies for immunoh istochemical examination were taken from representative skin lesions f rom 9 patients, one before and one from each side after treatment. The keratins 4, 13, and 8, were induced by treatment with topical 13-cis- RA. These keratins could not be detected in the biopsies taken before treatment nor in the biopsies derived from the cream-base treated side . Keratin 4 was induced in 6 of the 9 patients. induction of keratin 1 3, visualized with respectively. Keratin 8 visualized with mab LE41 an d M20 was induced in respectively 1 and 3 patients. No clear correlati on could be established between expression of keratins and clinical ef ficacy. Cellular proliferation tended to be increased at the 13-cis-RA treated side. No changes were found for the investigated parameters o f inflammation.