[Eruptive vellus hair cysts: prevalence and clinical features]

The eruptive vellous cyst is a benign clinical entity that arises from the infundibulum of the hair unit, characterized by asymptomatic yellowish or brownish papulocystic lesions. In most cases, chest and extremities are involved. Clinical and epidemiological information in Mexico is scarce.

To describe the prevalence and demographic and clinical findings of eruptive vellous hair cysts confirmed by histopatological study.

A descriptive, cross sectional study was performed, including all cases with histological diagnosis of eruptive vellous hair cysts from Hospital General Dr. Manuel Gea González database.

Seventeen cases were included, 11.7% of them had familiar history of eruptive vellous hair cysts; the most affected anatomical areas were chest, head and extremities (43.7, 37.5 y 31.2%, respectively). Differential diagnosis with epidermoid cysts and multiple steatocistoma was performed more frequently. The prevalence of our center from 1993-2012 was 1.6%.

The characteristics of our patients are similar to those described elsewhere. In addition, we estimated the real prevalence of this condition. They had a benign course and are a basically cosmetic concern, but represent a chronic and difficult to treat condition.