A revised and updated set of criteria and treatment recommendations by a global panel of dermatologists and ophthalmologists establishes a new approach to diagnosing and classifying rosacea by phenotype rather than by subtype.
Jerry Tan, M.D., panel co-chair and adjunct professor of internal medicine and dermatology, Western University, Windsor, Ontario, tells Dermatology Times that the position paper from the global ROSacea COnsensus (ROSCO) helps to clarify the diagnostic criteria for rosacea.
“The prior criteria were based on the 2002 recommendations from the National Rosacea Society. Because research has advanced over the last decade and a half, we have updated these diagnostic criteria to what is currently presented in the first ROSCO paper,” he says.
The ROSCO publication indicates that there only two specific diagnostic features, each of which can be individually diagnostic of rosacea; or major criteria, of which any two in combination can be diagnostic of rosacea.
“That’s a significant change from the prior recommendations from the National Rosacea Society. This increases the accuracy of diagnosis to focus on either centrofacial erythema or phymatous changes as diagnostic features independently,” Dr. Tan says. “In the past, any one of almost five different clinical criteria would be individually diagnostic of rosacea, which we felt needed revision.”
From old to new
An aspect that was important in the National Rosacea Society 2002 recommendations was the grouping of common presentations to subtypes. For example, erythematotelangiectatic rosacea was the combination of flushing, background erythema and telangiectasia. Subtype two, called papulopustular rosacea, was the presence of centrofacial erythema with papules and pustules.
“…with those two different subtypes, there are multiple phenotypes within those subtypes—phenotypes being the actual clinical sign or symptom presenting,” Dr. Tan says. “…that has led to confusion in terms of the research that is being conducted into rosacea. Much of the research conducted in the last decade and a half is based on grouping into these common presentations, as opposed to grouping into rosacea in general, with specific phenotypic segregation.”
To illustrate the change, Dr. Tan cites the example of a patient that presents just with background centrofacial erythema and not much in the way of telangiectasia or significant episodic flushing. Technically, he says, that patient did not have subtype one rosacea – erythematotelangiectatic - because the patient did not have flushing, nor did the patient have significant telangiectasia.
“Practically, in our current phenotypic-led classification, it’s not important to be grouping into subtypes. It’s more important to be categorizing based on patients’ presentation in terms of signs and symptoms,” he says. “So, if they simply presented with centrofacial erythema that would be diagnostic of rosacea, but we wouldn’t go onto subtype. We would just leave them as is, as that predominant phenotype. Then, we would manage them based on that, with various treatment options that are indicated for background centrofacial erythema.”
In the past, dermatologists treating a patient with erythematotelangiectatic rosacea, might have used multiple treatments to address each of the three phenotypes: flushing, centrofacial erythema and telangiectasia. There is no singular treatment for the three, according to Dr. Tan.