Demodex Bacteria and Low Sebum in PPR Sufferers

Written by David Pascoe on November 21, 2013 in Demodex Mites, research with 1 Comment

One more baby step in the quest to describe what role demodex mites might or might not play in how rosacea progresses as disease.

This latest paper tells us that in those rosacea sufferers who have a reaction to 2 proteins isolated from demodex related bacteria, you will also likely find low levels of sebum.

Demodex mites eat sebum so perhaps this result is not entirely unexpected. It might suggest, though, that the mites are thriving in this class of skin, causing an immune reaction whilst they multiply in larger than normal numbers.

We know that papulopustualar rosacea sufferers produce sebum with an altered fatty acid profile that may appeal to the mites.

We also know that PPR sufferers also have a increased immune response to B. Olernius, a bacteria that has been isolated from demodex mites.

Slowly, slowly more pieces of the jigsaw puzzle are coming together.

Paper Abstract

Correlation between serum reactivity to Demodex-associated Bacillus oleronius proteins, and altered sebum levels and Demodex populations in erythematotelangiectatic rosacea patients.

J Med Microbiol. 2013 Nov 18., Jarmuda S, McMahon F, Zaba R, O’Reilly N, Jakubowicz O, Holland A, Szkaradkiewicz A, Kavanagh K.

Department of Dermatology and Medical Mycology, University of Medical Sciences, Poznań Poland;

Rosacea is a chronic inflammatory condition that affects the skin of the face and the eyes. The etiology of rosacea is not clearly established but increasing evidence suggests a potential role for bacteria in the induction of the condition.

A role for Bacillus oleronius, originally isolated from within a Demodex folliculorum mite, in the etiology of the condition has been suggested.

The aim of the study was to determine whether a correlation existed between the level of sebum and the density of D. folliculorum in the skin of erythematotelangiectatic rosacea patients, and the reactivity of these patient’s sera to proteins of B. oleronius.

Serum reactivity to the 62 and 83 kDa B. oleronius proteins was found in 82.6% (62/75) of the rosacea patients and in 26.9% (14/52) of controls (p = 0.0016).

In the group of rosacea patients whose sera reacted to B. oleronius proteins, the level of sebum was statistically lower than in controls (p = 0.01).

The density of D. folliculorum on the face of Bacillus positive rosacea patients was statistically higher compared to controls (p = 0.0001).

Rosacea patients demonstrated increased Demodex populations on their faces and reduced sebum levels.

Their sera also showed reactivity to B. oleronius proteins suggesting a potential role for this bacterium in the etiology of rosacea.