Eruptive Vellus Hair Cysts

Abstract

Eruptive vellus hair cyst (EVHC) is a rare follicular developmental abnormality of the vellus hair follicles. The usual onset is between 17 and 24 years but may be congenital. It can arise sporadically or may be inherited in an autosomal dominant fashion. They are caused by an abnormality at the infundibular level of vellus hairs. They usually appear as yellow to reddish-brown papules over the chest, limbs, and abdomen. Histologically, cyst has a stratified squamous epithelium and it contains lamellated keratin and several vellus hairs. We present this rare case of a 12-year-old male because of its unusual morphology and distribution and also to generate awareness about this rarely diagnosed condition. To the best of our knowledge, no case of an axillary variant of EVHC has been reported till date.

Case for diagnosis. Unusual involvement of asymptomatic facial papular eruption: eruptive vellus hair cysts

“…The most relevant differential diagnosis for this atypical presentation of EVHC is steatocystoma multiplex, which shows a very marked clinical overlap and can be distinguished only by histopathological examination. 4 , 5 Other differential diagnoses are acneiform eruptions, milia, and folliculitis.…”

“…Topical lactic acid, topical and oral retinoids, and urea creams have also been tried with varying degrees of success. 2 , 5 …”

A Facial Solitary Vellus Hair Cyst: A Rare Entity

“…Vellus hair cysts, or trichofolliculomas, represent a rare category of benign skin lesions characterized by cystic spaces containing vellus hairs within the wall and lumen. These cysts typically manifest in regions with a high density of hair follicles, including the face, neck, and upper trunk [1]. While vellus hair cysts are generally asymptomatic and slow-growing, their relative rarity can contribute to diagnostic challenges, especially in atypical anatomical locations [2].…”