Chapter 81. Rosacea

Integration: Unifying Concept

It is extremely difficult to integrate the various features of rosacea because they are so disparate from one another. How are telangiectases, i.e., dilated end venules, related to papules that consist largely of perifollicular granulomas in company with telangiectases? And how is rhinophyma that represents infundibular cysts that have ruptured and induced suppurative, granulomatous, and fibrosing inflammation combined with prominent sebaceous gland hyperplasia related to keratitis? The answers are not known. Yet another conundrum is posed by the many clinical presentations of the papular expression of rosacea, among them, perioral and periocular dermatitis, rosacea-like tuberculid of Lewandowski, and lupus miliaris disseminatus faciei. In short, rosacea remains an enigma. One issue is clear, namely, that the mite Demodex folliculorum, long claimed to be the etiologic agent of rosacea, is irrelevant to the condition.

A diagnosis can be made of all variants of rosacea clinically, and of papular and rhinophymatous presentations of rosacea histopathologically if attributes of the process pictured in this chapter are identified.