Persistent Milia, Steatocystoma multiplex and Eruptive Vellus Hair Cysts: Variable Expression of Multiple Pilosebaceous Cysts within an Affected Family

Abstract

Background: Steatocystoma multiplex (SM) and eruptive vellus hair cysts (EVHC) are conditions characterized by numerous cutaneous cysts with a clinical resemblance, such as age of onset, location, appearance of the lesions and mode of inheritance, but with distinctive histologic features. Recently, some authors have proposed that the two conditions are variants of one entity originating in the pilosebaceous duct, while others suggest that SM and EVHC are two distinct entities, on the basis of the different expression of keratins. Milia are small round cysts, commonly involving the face. In 1994, Menni and Piccinno reported the first association, in a family, between persistent infantile milia in a 9-month-old girl and SM in the father. The authors hypothesized a relationship between these two conditions. Objective: We describe a family in which the mother showed cystic lesions and milia and her 4-year-old son and her 18-month-old daughter presented persistant infantile milia. Methods: In addition to the clinical and genetic documentation, a biopsy was performed in the son and two biopsies in the mother. Results: The histologic examination of one of the son’s milium-like papules showed in the superficial dermis a small cyst typical of a milium. In serial sections it was possible to see a connection with a vellus hair follicle by an epithelial pedicle. The histologic examination of one of the mother’s papules on the forehead showed a large round cystic structure with histologic features of EVHC. Close to the cyst wall, serial sections showed flattened sebaceous gland lobules. The histologic findings of the second biopsy taken from the chest showed the typical features of a steatocystoma. Conclusions: The relationship between milia, SM and EVHC is discussed; the three diseases should be considered as subtypes of multiple pilosebaceous cysts that may all present overlapping histologic features. The different level of the pilosebaceous duct where the cyst originates should explain the different clinical manifestations.

Eruptive vellus hair cysts on the face: a case report and literature review

“…Beş (%25) hastada eşlik eden başka bir hastalık (milia, steatokistoma multipleks, atopik dermatit, anhidrotik ektodermal displazi, diyabet ve kronik böbrek yetmezliği) izlendi. Hastaların 13'ünde (%65) lezyonların rengi deri renginden farklıydı, sadece birinde subjektif yakınma olarak kaşıntı mevcuttu 2,[6][7][8]13,14,16,[19][20][21][22][23][24][25][26] . Lezyonlardaki ağrı ve hassasiyete bizim olgumuz dışında rastlanılmadı.…”

A Case of Eruptive Vellus Hair Cysts That Developed on the Labium Major

“…Several authors have referred to the close relationship of between the EVHC and steatocystoma multiplex (SM). They suggested that both EVHC and SM may result from a cystic change of the pilosebaceous duct and so they may represent a spectrum of the same clinical entity 7,15 . Some case reports have described the simultaneous presence of EVHC and SM at one biopsy site 3,16,17 , or a hybrid cyst showing the combined histopathologic features of EVHC and SM 11 .…”

“…Kumakiri et al 2 experienced a localized form of EVHC on the forehead and they called it the facial variant, and there has since been several case reports of such facial variants. Less than 15 cases of the so-called facial variant form of EVHC, which is localized exclusively on the face, have been reported [1][2][3][4][5][6][7][8][9][10] . There have also been a few cases on an unusual site such as the buttocks [10][11][12] .…”

“…Their diameters range from 1 to 5 mm. They are usually localized on the chest and proximal extremities, but they may be present at unusual sites, including the face [1][2][3][4][5][6][7][8][9][10] , groin and buttocks [10][11][12] . Histologic examination reveals that the cysts are found in the mid-dermis, they are lined by several layers of squamous epithelium and they are filled with cutting vellus hair shafts and laminated keratin materials.…”

Two Pilosebaceous Cysts with Apocrine Hidrocystoma in One Biopsy Site: A Spectrum of the Same Disease Process?

“…13 at one biopsy site. Patrizi et al 5 suggested that milia and EVHC may represent an early sign of multiple pilosebaceous cystic disease and can be considered as a subtype of a multiple pilosebaceous cyst.…”