Eruptive Vellus Hair Cysts: An Underdiagnosed Entity.

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.