Milia

Basics

Description

  • Small (<3 mm) benign, keratin-filled cysts that present as white papules most typically on the face but may occur elsewhere on the body (palate, gingiva, genitals)
  • Subtypes include primary and secondary milia.
    • Primary: spontaneous
    • Secondary: secondary to trauma, medications, or another disease
  • Milia en plaque is a rare type of primary milia which typically occurs in the posterior auricular area as an erythematous plaque.
  • Multiple eruptive milia (MEM) occurs in children and adults when milia erupt in a large number; may be spontaneous, familial, or associated another disease

Epidemiology

  • Congenital milia is the most common form of primary milia.
    • 40–50% of newborns have milia.
    • Less common in premature infants
    • No gender or racial predilection
  • Secondary milia can occur in all age groups.

Risk Factors

  • Full-term newborns
  • Any bullous condition increases the risk of secondary milia, particularly epidermolysis bullosa and porphyria.

Genetics

  • No known genetic predisposition for primary congenital milia, the most common type of milia encountered in pediatrics
  • Milia may be a major feature of rare genetic diseases of the skin.
    • Loeys-Dietz syndrome
    • Oral-facial-digital syndrome type 1
    • Rombo syndrome
    • Bazex-Dupré-Christol syndrome

General Prevention

There are no known preventative measures for primary milia.

Pathophysiology

Retention of keratin and sebaceous material within the sebaceous collar surrounding fine vellus hair (primary milia) or eccrine sweat duct (secondary milia)

Etiology

  • Most commonly spontaneous in newborns
  • May be related to trauma or blistering conditions in older children

There's more to see -- the rest of this topic is available only to subscribers.