Unilateral Periocular Intralymphatic Histiocytosis, Associated With Rosacea (Morbihan Disease).

Intralymphatic histiocytosis is a rare reactive skin condition characterized by a nonspecific clinical presentation and, microscopically, by the collections of mononuclear histiocytes within the lumina of dilated lymphatic vessels. We report a rare case of intralymphatic histiocytosis associated with rosacea and prominent periocular edema (Morbihan disease). The patient is a 56-year-old woman with a 12-year history of rosacea who suddenly developed edema of the right upper eyelid that persisted 6 months before she sought medical advice. Because of an unclear clinical diagnosis, surgical excision of the edematous upper eyelid was performed. The histologic slides showed interstitial edema of the dermis with dilated vascular channels and small epithelioid cell granulomas around hair follicles. In addition, there were aggregates of cells inside numerous lymphatic vessels that were immunohistochemically positive for CD45, CD4, CD68, CD163, CD64, CD14, CD11c, and lysozyme and negative for CD3, CD20, CD30, CD56, S100, CD1a, and langerin.