Milium, Milia

Key Points
Harmless, very common skin condition which may affect various parts of the body, typically found around the eyes
May be caused by a variety of factors, but thought to be related to undeveloped sebaceous glands
Consists of small, pearlescent white or yellow bumps under the top layer of skin

Milium is a harmless and very common skin condition, which may affect various parts of the body, but is typically found around the eyes. The condition consists of small, pearlescent white or yellow bumps, which are small keratin cysts.

There are several variants of the condition. Neonatal milia appear in approximately half of newborns, and consists of lesions typically on the nose, but which may appear in the mouth interior, scalp, upper torso, and face. Primary milia is typically found around the cheeks, forehead and eyelids, as well as the genitals, and is persistent in some cases. Juvenile milia are typically found in association with assorted genetic disorders which present at birth, such as Rombo syndrome, basal cell nevus syndrome, pachyonychia congenita, and Gardner syndrome. Milia en plaque consists of milia which form on an irritated plaque, typically on the cheeks, jaw, behind the ears, or the eyelid, and may be associated with other skin conditions such as lichen planus, discoid lupus erythematosus or pseudoxanthoma elasticum. Multiple eruptive milia presents as groups of numerous lesions which form over a long period, which may be accompanied by itching. These lesion groups typically appear on the upper arms, face, or upper torso. Traumatic milia presents at the site of an injury to the skin. Milia are also occasionally seen as a drug reaction to some topical medications, include hydroquinone, 5-fluorouracil, and corticosteroids.

Milia can develop due to a variety of factors, but their formation may be related to sebaceous glands which do not develop before birth. Injury and drug reactions may also play a role in some cases. Milia are very common, and affect all age, ethnic and gender groups.

Differential Diagnosis (Other conditions with similar appearance)
Acne Vulgaris
Syringoma
Trichoepithelioma

Diagnosis
Key Points
Diagnosis based on appearance of the affected area
Biopsy may be performed to confirm diagnosis and rule out other conditions

Diagnosis of milia is typically based on the appearance of the affected area. A skin biopsy may be performed to confirm diagnosis and to rule out other conditions.

Treatment
Treatment is generally not required, as the condition is benign
When treatment is required, destruction is the most common
In cases where lesions are widespread, other therapies may be recommended

Milia do not typically require treatment, as they are benign and usually resolve themselves within several months. Any injury to the affected area should be avoided, as this may exacerbate the condition. When treatment is required, destruction is the most common method, using various techniques such as diathermy, curettage, cryotherapy, and surgical excision. In persons with lesions which are widespread, topical retinoids, chemical peels, dermabrasion, and laser therapies may be helpful in resolving the condtion. Milia en plaque is often treated with antibiotic medications, and milia due to drug reaction should clear when the offending medication is stopped.