Rosacea and demodex mites
Stanisław Jarmuda,1 Niamh O’Reilly,2 Ryszard Żaba,1 Oliwia Jakubowicz,1 Andrzej
Szkaradkiewicz3 and Kevin Kavanagh2. The potential role of Demodex folliculorum mites and bacteria in the induction of rosacea. J. Medical Microbiology (August 2012)
Rosacea is a chronic skin disorder that affects more than ten million Americans; the disease has been called "the Celtic curse" because it affects more often people of Northern European descent. Women are more likely to suffer rosacea of the milder form, and men more frequently have the severe form, which involves deformity of the nose. Rosacea nearly always appears on sun damaged skin. Except for cases precipitated by use of steroids, the causes of rosacea are not known. At present there is no good treatment that will work for all patients, and the best that can be done is to prevent irritation and inflammation.
The review in the news (Jarmuda et al, 2012) re-introduces a very old player, the Demodex skin mite, and its companion bacterium, Bacillus oleronius, as agents in the development of rosacea, incorporating them in way that complements what has been learnt of rosacea as immunity related disease. In the first stage a specific (innate or acquired) immune defect against Demodex allows the proliferation of the mite; in the second stage, probably when some mites penetrate into the dermis, the immune system is suddenly stimulated and gives rise to an exaggerated immune response against the Demodex, resulting in the papules and the pustules of the rosacea. Several molecular features of its inflammatory process have been identified: an overproduction of Toll-Like receptors 2, of a serine protease, and of abnormal forms of cathelicidin. (Please see the SAS May 2008 Newsletter on the role of antibiotic peptides in rosacea).
This recent re-evaluation of the role of skin mites in rosacea is unlikely to change treatment in the short term, because Demodex had already been blamed for rosacea and treatments to kill the mites and antibiotics (for possible bacterial involvement) had already been tried without too much success.
What can you do about rosacea? Protect your skin from the sun, infection and weakening of the skin barrier. Steroids are not an option, so to control inflammation, try our anti-inflammatory cream. Many clients have found relief using 4-ethoxybenzaldehyde mixed with a base cream. Our rosacea control serum with epidermal growth factor works for others. I usually ask clients to try these products one by one and see whether one of them helps. Azeloyl glycine is another option. With such a complicated condition as rosacea, we should expect that at different stages the skin will respond in different ways to the same treatment. You could also try our Glycan-7 cream, it may help both with strengthening the skin barrier and enhancing the immune response against Demodex.
Yamasaki, Kenshi; Di Nardo, Anna; Bardan, Antonella; Murakami, Masamoto; Ohtake, Takaaki; Coda, Alvin; Dorschner, Robert A.; Bonnart, Chrystelle; Descargues, Pascal; Hovnanian, Alain; Morhenn, Vera B.; Gallo, Richard L. (2007) Increased serine protease activity and cathelicidin promotes skin inflammation in rosacea Nature Medicine 13(8), 975-980.
Forton FM. (2012) Papulopustular rosacea, skin immunity and Demodex: pityriasis folliculorum as a missing link. J Eur Acad Dermatol Venereol. 26:19–28