ACNE-LIKE ERUPTION INDUCED BY PSEUDOXANTHOMA ELASTICUM - EFFECTIVENESS OF LIQUID-NITROGEN CRYOTHERAPY

We report a case of pseudoxanthoma elasticum associated with an acneif orm eruption involving the cervical area. When she was 16 years-old ou r patient was diagnosed with pseudoxanthoma elasticum, affecting the s kin (flexural, cervical and neck areas) and the eyes (bilateral ocular angioid streaks). Ten years later, acneiform lesions (inflammatory an d comedones) developed on these lesions:the inflammatory lesions were characterized by phagocytosis of pathological elastic fibers inducing granuloma the histological aspects of pseudoxanthoma elasticum were ob served around large comedones. This association is rarely reported and we think that atypical, cervical acneiform lesions may be an indicati on of pseudoxanthoma elasticum. The mechanism for this association is not clearly understood. In our case, Von-Kossa staining was negative f or the granulomatous lesions and positive for the comedones: calcifica tion could protect elastopathic fibers from phagocytosis. Treatment is difficult: anti-acneic treatments are not effective except for tetrac ylines, the anti-inflammatory effects of which can improve granulomato us lesions. As its efficacy has been reported in elastosis perforans s erpiginosa, we used liquid nitrogen cryotherapy on the inflammatory le sions with good results (separation of epidermis from dermis perhaps p romoting transepithelial elimination of the abnormal dermal elastic ti ssue).