Xanthoma is characterized by the accumulation of fat under the surface of the skin. It can appear anywhere on the body and ranges in size from small to large and to a diameter of 3 inches. It is considered a common condition, particularly among the elderly people. It is also indicative of lipid metabolism disorders such as hyperlipidemia and associated with a high risk of coronary artery disease. Other conditions associated with xanthoma include certain types of cancer, diabetes, hypothyroidism and primary biliary cirrhosis. The goal is to identify the underlying cause such as the lipid disorder and their treatment usually resolves the xanthoma. The treatments for xanthelasma include laser vaporization, excision, topical trichloroacetic acid and electrodesiccation.
There are various types of xanthoma based on the location of the body and how they develop.
- Xanthelasma palpebrum is the most common cutaneous xanthoma characterized by the yellowish plaques that develop symmetrically on upper and lower eyelids. The lesions can be soft and flat papules. These lesions generally begin as small bump and increase in size with time. Some of the triggering factors of this include thyroid dysfunction and diabetes mellitus. Although it is a benign condition, patients often consult dermatologists or plastic surgeons for lesion removal.
- Tuberous xanthomas
The most common hyperlipidemia underlying this condition is familial hypercholesterolemia which is caused by the defects in certain genes. Tuberous xanthomas is characterized by the firm, painless nodules developing around the pressure areas such as the surfaces of elbows, knees, knuckles and buttocks. The lesions can also join together to develop multilobated masses.
- Tendinous xanthoma
Tendon xanthomas are subcutaneous nodules that appear in fascia, ligaments and tendons which can particularly occur in the Achilles tendon. This type is also associated with the severe hypercholesterolemia and high levels of LDL levels.
- Eruptive xanthomas
These are cutaneous manifestations of hyperlipidemias and typically present as yellow-orange papules and often associated with extreme hypertriglyceridemia in individuals with diabetes mellitus. They commonly erupt over the shoulders, arms, legs and the buttocks but could also appear all over the body. The lesions can be tender and may itch but the condition could resolve spontaneously over a few weeks.
- Diffuse plane xanthomatosis
This is characterized by the large reddish-yellow plaques over the chest, face, buttocks and on the skin folds such as the armpits and the groins. This can be divided into two groups: group 1 is associated with high lipids due to familial hyperlipemia or biliary cirrhosis and group 2 is the normal lipid levels. Around 50% of affected cases will have a malignancy of the blood such as leukemia.
- Xanthoma disseminatum
This is a rare benign condition presenting extensive cutaneous and mucous membrane xanthomas. It occurs as multiple, red-brown to yellow papules and nodules which are evenly spread on both sides of the face and the trunk. It can continue to affect the armpits and the groins. It could also manifest in the central nervous system, the respiratory and gastrointestinal tract. Although the lesions in important anatomical locations could result in morbidity and mortality, it is a self-limiting condition that eventually improves by itself but could persist for years.