Xanthoma

• Xanthelasma palpebrum is the most common type where soft, white/yellow, flat papules or plaques are found on the upper or lower eyelid (see image below).
• Eruptive xanthomas are crops of small (2–5 mm), red-yellow lumps over the buttocks, elbows, knees and shoulders. They may spread like a rash and can spread further to involve your limbs or mouth. They can be a sign of very high blood lipids and other underlying illness. They may go away on their own, or after treatment for the underlying cause, over a few weeks (see image below). 
• Tendinous xanthomas develop in the skin over tendons and ligaments, eg, on the hands, Achilles tendon, elbows or feet. This is also associated with high blood cholesterol (hypercholesterolaemia and/or high LDL levels.)
• Tuberous xanthomas are firm, painless red to yellow coloured lumps that can grow very round and large. They appear over pressure areas, eg, the knees, elbows, heels and buttocks. They are often associated with high cholesterol levels. 
• Diffuse plane xanthomatosis involves flat papules or patches occurring anywhere on the body. When they are found around the fingers and toes, this is commonly a sign of familial high blood cholesterol (when it is genetic or runs in the family). 

Image credit: DermNet NZ

Xanthomas are generally painless white or yellow lumps found on different parts of your body. They may be a sign of an underlying lipid or metabolic problem that's led to increased cholesterol or lipids circling in your blood. Xanthomas are your body's way of storing the extra fats, which is why they can be reabsorbed and go away when the underlying conditions are treated. 

Conditions that cause xanthomas or contribute to their growth include:

• high cholesterol and inherited metabolic disorders such as familial hypercholesterolemia (high blood cholesterol caused by a gene that runs in families)
• certain cancers
• diabetes
• hypothyroidism
• primary biliary cirrhosis
• pancreatitis.

If you think you may have a xanthoma appearing, show your doctor as it can be a pointer to other problems. You may need to have a blood test to check for cholesterol and lipid levels, metabolic disorders, liver function, thyroid problems and diabetes.

You can just leave them alone, as the growths are painless and treatment is for visual or cosmetic benefit only.

However, if you wish to treat them the options include:

• Treating any underlying causes of high cholesterol and lipids in the blood, eg, with dietary changes and medications (if recommended). This can reduce their size and prevent new ones appearing.
• Topical trichloroacetic acid.
• Electrodesiccation.
• Laser vaporization along with surgical removal. However xanthomas can reoccur or new ones may appear if the underlying causes are not treated.

Keeping your blood cholesterol and lipids within a normal range will help prevent xanthomas. This can be achieved through healthy eating, maintaining an ideal body weight and getting regular exercise. Your doctor or nurse can talk through a plan to help you, based on your symptoms and results. Xanthomas can be a warning sign for cardiovascular disease, and eating healthily and exercising can slow the progression of this too.

If your whānau members have xanthomas, ask your doctor about a lipid test to check for familial (genetic) lipid disorders in your family.