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Pseudofolliculitis
Pseudofolliculitis
Clinical features Pseudofolliculitis (pseudofolliculitis barbae, pseudofolliculitis cutis) presents with an acneiform papular and pustular eruption on the beard area. Comedones are not a feature. It develops as a consequence of the reentry of a terminal hair shaft through the epidermis and occurs most often in males with curly hair, but is also seen in women in the pubic region following cosmetic shaving.1โ5 Pseudofolliculitis occurs predominantly in patients of African, African-American, and Hispanic origin.2,3,6 The pathogenesis appears to be multifactorial, and seems to relate to the shape of the hair follicle, the hair cuticle, and the direction of hair growth.3 The presence of curly hair and a single-nucleotide substitution in the gene encoding keratin 75 act in concert to confer an increased risk for the development of the condition.2,7 The
penetration is facilitated by the sharp ends produced on hairs by shaving and the curliness of the hair bringing the cut end back into contact with the skin surface.5 Alternatively, the penetration may occur laterally through the superficial part of the follicular infundibulum following partial retraction of the hair after close shaving. A hypertrophic form of the disease has been described in renal transplant recipients.8
Histologic features The process is not a true folliculitis, and is not usually associated with infection. The reentry of the hair shaft provokes a foreign body granulomatous reaction with accompanying fibrosis. The inflammation is predominantly histiocytic with occasional multinucleate giant cells. Secondary infection may result in superimposed suppuration. Resolution occurs rapidly, with slight scarring, once the hair shaft is removed.
869 Plague