Size: 0.1 to 0.4 mm in length, with 4 pairs of stubby legs.
Factors affected response:
(1) number of mites
(2) host response, which may include allergic or immune responses
(3) secondary infection
Typical locations:
(1) forehead and eyebrows
(2) nose
Other sites may be affected but usually go unnoticed.
Clinical findings:
(1) folliculitis not responding to antibacterial agents
(2) dry erythema with follicular scaling. Minor rubbing of the affected area may result in marked erythema.
(3) rosacea
(4) reaction to ruptured follicles
A suggestive finding is improvement of the skin condition following use of anti-mite shampoo.
Demonstration of mites:
(1) skin scrapings, especially following production of sebaceous secretions
(2) tape preparation, using a clear tape on the skin that can be applied sticky side down to a glass slide.
(3) Application of petroleum jelly for several hours. The jelly is then gently scraped off and applied to a glass slide.
(4) skin biopsy, which can help gauge the host response in more severe infestations
Therapy:
(1) 200 µg ivermectin per kg body weight once orally followed by weekly use of topical permethrin cream (Forstinger et al)
(2) Lindane (gamma benzene hydrochloride) can be used but can be toxic if misapplied or allowed to be absorbed.
(3) Periodic use of anti-mite shampoo may be sufficient for less severe cases. It is important not to get the shampoo into the eyes, and not to leave the shampoo on for too long.
