The American Journal of dermatopathology
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Demodex is a saprophytic mite in humans commonly present in the pilosebaceous units, which has been implicated as a pathogen in several skin conditions. The clinical presentation and histopathology of Demodex folliculitis of the scalp have been described in only a few case reports. This study was performed to further elucidate the clinicopathological features of this entity. ⋯ All 4 cases responded completely to metronidazole therapy. In conclusion, Demodex is infrequently found in scalp biopsies for hair loss and alopecia, and, in most cases, it does not seem to be pathogenic. Occasionally, however, it is associated with folliculitis characterized by hair loss, erythema, scales, and pustules clinically; neutrophilic and/or mononuclear-cell folliculitis with occasional granulomas histopathologically; and a prompt response to anti-Demodex therapy.