Eruptive vellus hair cyst: An uncommon and underdiagnosed entity

Abstract

Eruptive vellus hair cyst (EVHC) is a rare follicular developmental abnormality of the vellus hair follicles. They are usually seen in children, adolescents, or young adults and manifest as reddish-brown smooth papules most commonly involving the chest, limbs, and abdomen. An 18-year-old male presented with asymptomatic papules on the trunk and flexor aspect of both forearms for the past 2 years. There was no family history of similar lesions. His medical history was also not contributory. A clinical diagnosis of steatocystoma multiplex and chronic folliculitis was given, and a punch biopsy from the papule was performed and sent for histopathological examination. On microscopic examination, a final diagnosis of EVHC was rendered. The patient was advised topical treatment of retinoic acid cream (0.05%) for 6 months, and he is currently under follow-up period. Due to its rarity and resemblance to many similar entities, histopathological examination plays a major role in establishing a definite diagnosis and further proper management of the patient. We report this unusual case to generate awareness about this rarely diagnosed condition.

Mosaic proximal trisomy 13q and regular trisomy 13 in a female patient with long survival: Involvement of an incomplete trisomic rescue and a chromothripsis event

“… 2009 ; Faletra et al, 2012 ). Our patient also had clinically diagnosed EVHC, which are usually sporadic, although an autosomal dominant inheritance pattern has also been proposed (Anand et al, 2018 ). However, these lesions could be originated by the MT13, as hidradenitis suppurativa has been reported in an MT13 patient (González del Angel et al, 2014 ), and also in a patient with mosaicism for trisomy 13q distal (Faletra et al, 2012 ).…”

Asymptomatic Blue-Green Bumps on Skin Inherited from Father to Daughter in an Indian Family

“…Usually, the EVHC located on the trunk is distributed near the midline, whereas in the present cases, the midline was relatively spared [1]. EVHCs may be easily mistaken for conditions with similar clinical presentations such as comedonal acne, milia, steatocystoma multiplex, keratosis pilaris, and syringomas [2,3]. It is likely that EVHCs are underdiagnosed due to the lack of awareness about this entity amongst the dermatologists.…”

“…These may be skin colored or bluish green and are usually dome-shaped, soft tender papules with smooth surface, chiefly affecting the anterior chest, upper trunk, and upper limbs [1]. The histopathological findings of EVHCs are monomorphic too, characterized by collection of multiple horizontally and obliquely sectioned vellus hair shafts in a cystic cavity [1][2][3]. Reduced Ki-67 expression on IHC suggests that EVHCs are clinically stable lesions with a low proliferation rate [4].…”

“…We prescribed topical tretinoin 0.025% which showed no benefits. Although various treatment modalities for EVHCs have been tried such as topical retinoids, electrocautery, incision/excision, CO 2 laser, and Erbium-YAG laser, but they failed to provide complete remission [1][2][3]13]. Therefore, studies concerning pathogenetic mechanisms of EVHCs and potential therapeutic options for EVHCs are warranted in future.…”

Eruptive Vellus Hair Cysts

“…The cyst cavity contains a variable amount of loose lamellated keratin and multiple transversely and obliquely cut vellus hairs. [ 3 ] The cyst wall may be present in continuity with a rudimentary hair follicle or arrector pili muscle. In general, no sebaceous glands are present in the cyst wall.…”