Pathogenesis associated with hair follicle mites (Demodex spp.) in Australian Aborigines

Abstract

Demodex folliculorum and D. brevis are found in different habitats in the skin: the former in the hair follicles, the latter in the sebaceous glands. Both seem minor pathogens--merely harvesting the cells of their respective habitats. D. folliculorum was found aggregated (all stages) and plugging the follicular orifices; D. brevis, on the other hand, was usually solitary. In one case marked degeneration of the sebaceous gland, with leukocyte invasion, was associated with D. brevis. No correlations were discovered between either of these species and the gross condition of the skin. Positive samples were obtained from both mainland and island populationf of Aborigines. Incidence values obtained were 66.6% for males and 80% for females; in the latter, the sample was small (5) and their ages over 34 years.

The Hair Follicle Mites <i>Demodex folliculorum</i> and <i>Demodex brevis</i>: Biology and Medical Importance

“…The two Demodex species found in man occur worldwide and have been recovered in all investigated racial groups of man [Nutting, 1964;Nutting and Green, 1976], The incidence of infestation is distinctly related to the age of the patients examined (table I).…”

Prevalence of Demodex in Health Personnel Working in the Autopsy Room

“…8,13,27 In our study, no statistical significance could be found between the prevalence of Demodex and the number of times people washed their face and bathed.…”

“…13,25,27,28 Nutting and Green 27 found a Demodex frequency of 72% in skin with dermatitis and 66.7% in normal skin. Marufi and Köylüoglu 28 reported 44% Demodex in skin with dermatitis and 21% in normal skin.…”

Demodicidosis Mimicking Granulomatous Rosacea and Transient Acantholytic Dermatosis (Grover’s Disease)

“…Some authors distin guish between typical rosacea and a rosacea like dermatosis with smaller papules, super ficial granulomas, and predominating fol licular lesions [17], The mite D. folliculorum, as most of the mites, fed on sucking the content of the kera tinizing and sebaceous cells of the follicle wall [18]. This behavior may eventually, es pecially when the mites are numerous, result in destruction or rupture [19] of the follicle wall leading to penetration of mites in the dermal connective tissue. Additionally, it has been suggested that the mite itself is able to produce an enzyme-like substance which allows destruction of the follicle wall [3].…”