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Eruptive hairy cysts

What is vellus? hair?

Hairy hairs are fine, blonde hairs normally grow on the face, trunk and limbs (in contrast to terminal hairs, which are longer, pigmented, and that arise mainly in the scalp, beard, armpits and pubic area).

What are eruptives? hair cysts?

Eruptive hairy hair cysts are small papules containing hairy hairs. They are usually found in the central chest. Eruptive hairy hair cysts are quite rare.

Who Has Eruptive Hairy Hair Cysts?

Eruptive hairy cysts are likely to be family when they occur in early childhood. Sporadic forms tend to develop later in adolescence. Boys and girls are equally affected.

They are usually an isolated finding and are not associated with other skin abnormalities. Eruptive hairy hair cysts sometimes arise in children with anhydrotic and hydrotic agents. ectodermal dysplasia, multiple steatocystoma or pachyonychia congenital

What Causes Eruptive Hairy Hair Cysts?

Eruptive hairy hair cysts are believed to be the result of occlusion (blocking) at the level of the infundibulum (the part of the hair follicle just below the epidermis), subsequent cystic dilation (enlargement) of the hair follicle and secondary atrophy (wilting) of the hair bulb. This is probably a developmental abnormality.

Curb gene mutations are a likely association in family cases when they have a autosomal dominant inheritance. This means that an abnormal gene comes from one of the parents. In some cases, mutations have occurred in the gene encoding keratin 17 (K17).

What are the clinical features of eruptive hairy hair cysts?

Hair cysts usually appear as small red or brown bumps on the breastbone. They have also been reported to occur in the extremities. There may be few or numerous cysts, sometimes reaching hundreds.

The individual lesions are usually small smooth dome-shaped papules, 2–3 mm in size. They may be dimpled or umbilical and sometimes have a scaly or crispy surface.

Eruptive hairy cysts


Eruptive hairy cysts


Eruptive hairy cysts


Eruptive hairy cysts

What other conditions should be considered?

Epidermoid /infundibular cysts and multiplex steatocystoma also present as asymptomatic papules or nodules about him previous chest.

the differential diagnosis may include folliculitis and keratosis pilaris

How are eruptive hairy cysts diagnosed?

Diagnosis of eruptive hairy hair cysts is often made clinically, due to the typical age of onset, site of injury, and appearance.

Incision or prick of the cyst and examination of the contents under a microscope will reveal the hairs.

A skin biopsy You can confirm the diagnosis. Histopathology stratified samplescaly epithelium with a granular layer surrounding a cystic space filled with laminated keratin and a variable number of hair shafts.

Histopathology of the eruptive hairy cyst


Low-power view of the cyst


Capillary stems within the cyst


High power view

What is the treatment for eruptive hairy cysts?

In many cases, treatment is unnecessary since the injuries are harmless. The cysts go away on their own in about 25% in children.

Long-term use of keratolytic Creams containing urea or salicylic acid can be helpful. Tretinoin and oral retinoids (Isotretinoin, acitretin) have been used with limited success.

Individual injuries can be removed surgically by excisioncurettage cryotherapy or To be but this is likely to cause scarring.