Medical research has often pointed to the microscopic skin mite Demodex folliculorum as a potential factor in rosacea, specifically the bumps and pimples of subtype 2 (papulopustular) rosacea. Now the mite has surfaced again as a possible offender and therapeutic target for rosacea at this year’s American Academy of Dermatology summer meeting. 

In a presentation on the management of facial skin disorders, Dr. Erin Lesesky, assistant professor of dermatology at Duke University, summarized a meta-analysis published in 2010 in the Archives of Dermatology that looked at 48 case-controlled studies on Demodex to analyze the potential association between the presence of Demodex and the development of rosacea.¹ The study found a significant association between the relative presence of the mites and the development of rosacea, suggesting that the microscopic mites may be involved in the disease process. The study authors also proposed that increased mite density in skin might trigger inflammatory responses, block hair follicles or help transmit other bacteria in the skin, leading to signs and symptoms of rosacea.

Dr. Lesesky noted that the strong results of the study may point to the possibility of Demodex as a missing link for treatment of patients with subtype 2 rosacea who don’t respond to traditional therapy.

“Patients who don’t respond to traditional treatment for papulopustular rosacea may have an increased density of Demodex mites or an increased immune response to these mites,” Dr. Lesesky said.  “Alternative treatments targeting Demodex might be useful for successful patient management.”

1. 1. Zhao YE, Wu LP, et al. 2010 Aug. Retrospective analysis of association between Demodex infestation and rosacea. Archives of Dermatology. 146(8):896-902.