Demodicosis is caused by demodex mites, also known as hair follicle mites.


Causes

Demodex mites, mostly demodex folliculorum and demodex brevis, are found in the hair follicles and sebaceous glands of humans, especially facial hair follicles with strong sebaceous gland secretion, mostly in the forehead and nose, rarely in the extremities and other areas, and can hardly be found in children under 5 years of age. Demodex mites feed on sebum and cell debris in the sebaceous glands or hair follicles and are harmless to humans, but are often accompanied by expanded hair follicles, rosacea, acne vulgaris, or other diseases that may be related to hair follicle or sebum dysfunction.

Figure 1 demodex mites


Signs and Symptoms

Demodex mites can be found in facial itches with or without erythema, acneiform rash without telangiectasia or flushing, blepharitis, seborrheic dermatitis, papulopustules on the face or scalp, rosacea-like demodicosis, rosacea, and perioral dermatitis.

Figure 2 demodicosis


Diagnosis

If there are clinical manifestations and live demodex mites found in microscopy, the disease can be diagnosed.


Treatment

Topical benzoyl peroxide with or without erythromycin, benzyl benzoate, benzene hexachloride, metronidazole, permethrin, and oral ivermectin are effective.