Steatocystoma multiplex is a benign autosomal dominant congenital condition resulting in multiple cysts on body.
The onset at puberty is presumably due to hormonal stimulus of the pilosebaceous unit. They most often arise on the chest and may also occur on the abdomen, upper arms, armpits and face. In some cases cysts may develop all over the body.
The cysts are mostly small (2-20 mm) but they may be several centimetres in diameter. They tend to be soft to firm semi-translucent bumps, and contain an oily, yellow liquid. Sometimes a small central punctum can be identified and they may contain one or more hairs (eruptive vellus hair cysts). They may become inflamed and heal with scarring, like acne nodules .
Steatocystomas are thought to come from an abnormal lining of the passageway to the oil glands (sebaceous duct).
Localised, generalised, facial, acral, and suppurative types of steatocystomas multiplex have been described.
It is associated with defects in Keratin 17.
Individual cysts can be removed surgically. In most cases, small incisions (cuts into the skin) allow the cyst and its contents to be extracted through the opening. If it is tethered to the underlying skin, excision biopsy may be necessary. Cysts can also be removed by laser, electrosurgery or cryotherapy. Inflammation can be reduced with oral antibiotics. Oral isotretinoin is not curative but may temporarily shrink the cysts and reduce inflammation.