Circumscribed Alopecia: An Unusual Manifestation of Pediculosis Capitis

Abstract

A healthy 10-year-old girl was referred for evaluation of patchy hair loss on the scalp of longer than 6 months duration. She had been diagnosed and treated for head lice approximately 1 month before onset of the hair loss. Examination of the scalp showed discrete ovoid patches of hair loss at the vertex scalp. A scrape of the area of hair loss was performed, and a nit was visible on microscopic examination. Focal hair loss may represent an atypical manifestation of ongoing pediculosis capitis.

Pediculosis capitis grave en una niña inscrita en una guardería

“…Si la pediculosis capitis persiste, el rascado rara vez altera la epidermis del cuero cabelludo, pero puede causar su despigmentación y adelgazamiento, lo que propiciaría las infecciones secundarias por bacterias que llevan a desarrollar la presencia crónica de impétigo del cuero cabelludo, forunculosis, excoriaciones, costras hemáticas y linfadenopatías locales 7 , 10 , 12 , 14 . La alopecia focal se ha descrito como una presentación atípica de la pediculosis capitis (zonas de alopecia fronto-temporal bilateral) 6 , 15 .…”

Paediatrics: how to manage pediculosis capitis

“…Patchy hair loss has rarely been described as a manifestation of pediculosis capitis. 49 Pediculid, an id reaction secondary to pediculosis capitis, manifesting as pruritic, erythematous, maculopapules or papulovesicles distant from the primary inflammatory focus has been reported. 47 , 48 Rarely, plica polonica characterized by diffuse matting of scalp hair with irreversibly entangled plaits stuck together with dirt and exudates resembling a ‘bird’s nest’ may be observed with florid pediculosis infestation.…”