Sebaceous Cysts

Question 1

Define:

Answer 1

Refers to either an epidermoid (arising from the epidermis) or pilar (arising from hair follicles)

These are epithelium lines, keratinous and debris filled cysts

DO NOT CONTAIN SEBUM OR ORIGINATE FROM THE PILOSEBACEOUS GLAND.

Question 2

Aetiology:

Answer 2

Arise when the pilosebaceous gland gets occluded

Can be caused by traumatic insertion of epidermal elements into dermis

Embryonic remenants

Question 3

Risk factors:

Answer 3

Gardener’s syndrome - autosomal dominant characterised by polyps in extracolonic regions

Question 4

Symptoms:

Answer 4

Non-tender + slow growing

Often multiple

Common in hair baring areas

red, hot, tender and superimposed if infected (infection is common)

discharge cheesy and foul smelling pus

Question 5

Signs:

Answer 5

Firm + round + subcutaneous nodule of varying size

Characteristic central punctum (epidermoid only)

Foul pus (granular and creamy) exits from the punctum

Question 6

Investigations:

Answer 6

none needed usually clinical diagnosis

FNA or skin biopsy to exclude other causes