To the Editor.—
Demodex mites are parasites normally present in human skin. In up to 10% of skin biopsy samples, these organisms can be seen as an incidental finding colonizing the pilosebaceous complex.1 It is well known that the greatest concentration of Demodex is found in areas where sebaceous glands are numerous and sebum production is pronounced.2 Aylesworth and Vance1 demonstrated that the face is by far the most heavily infested area, especially the temple and the nasal region. To a lesser degree, Demodex have been found around nipples, neck, chest, back, and genital regions.3 An isolated report has shown the presence of Demodex in ectopic sebaceous glands of the oral mucosa.4 This observation suggests that Demodex has an affinity for the sebaceous glands, and that hair follicles need not be present for the mites' survival.
Materials and Methods.—
Formaldehyde-fixed paraffin-embedded sections from a consecutive series
Jimenez-Acosta F, Planas L, Penneys N. Demodex Mites Contain Immunoreactive Lipase. Arch Dermatol. 1989;125(10):1436-1437. doi:10.1001/archderm.1989.01670220134028