Sebaceous cyst is dome-shaped sac formed under the skin due to rupture or blockage of the duct of the sebaceous glands. It contains a thick, sticky, cheesy material called sebum which builds up over many years and causes the cyst to expand gradually.

Causes

It can cause due to following reasons-

• Damaged follicle involving an acne.
• Injury to that area.
• A sebaceous duct which doesn’t grow correctly.

Clinical Features 

• A harmless and firm skin colored nodule or lump under the skin with a central opening.
• Usually painless and at times get infected which then turns red, swollen and painful on touch. At this stage the cyst may need surgery.
• On draining, a white, creamy, greasy foul-smelling fluid comes out.
• Often arises from an infected hair follicle
• Mostly located on the scalp, trunk, face, buttocks, neck, back and genitals.

Treatments

• Some cysts can be resolved on their own or by antibiotics.
• Intralesional steroids can be given in case of swelling, so we need not drain the cyst.
• Smaller and painful sebaceous cysts can be punctured and drained.
• Prominent cysts with infection may need a removal by simple surgery by giving a local anesthetic. In this procedure a simple incision is given on the cyst and the intact sac with all the contents is removed and the wound is stitched.