This article is from the Rosacea Disorder FAQ, by David Pascoe pascoedj+usenet@spamcop.net with numerous contributions by others.
The panel of Rosacea experts agreed on the following broad, non exclusive
text (i.e. there are other factors and types that come into play).
"The system divides rosacea into four subtypes: erythematotelangiectatic,
papulopustular, phymatous, and ocular. As presently worded, papulopustular
rosacea is noted as often being observed following or with
erythematotelangiectatic disease and phymatous rosacea as following or
occurring together with either erythematotelangiectatic or papulopustular
rosacea. However, Dr. Wilkin emphasized that while those descriptions are
consistent with common concepts about rosacea natural history, they are
provisional and subject to change."
"In its current iteration, the classification system excludes rosacea
fulminans, steroid-induced acneiform eruptions, and perioral dermatitis
without rosacea signs from the diagnosis of rosacea."
 
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