A xanthoma is a yellow-orange lump in the skin made up of fat. The fat within xanthomas accumulates within a type of immune cell, called macrophages.
Xanthomas have various types according to their clinical presentation. Different types of xanthomas have different causes and associations. While many xanthomas are idiopathic, some xanthomas may be associated with fat metabolism disorders including lipid metabolism disorders, blood disorders, or even rarely, genetic disorders
Different types of xanthomas look differently:
- Xanthelasma of eyelids: soft yellow irregular lumps and bumps on both eyelids
- Tuberous xanthoma: firm, painless, red-yellow lumps on elbows, knees, heels and buttocks
- Tendinous xanthoma: firm nodules on Achilles tendon and tendons of back of hands
- Eruptive xanthoma: numerous red-yellow bumps on limbs, buttocks, skin folds and mouth
- Palmar creases plane xanthoma: yellow soft bumps on creases of the palms
- Intertriginous plane xanthoma: yellow soft eruption on skin folds and web of fingers
- Diffuse plane xanthoma: large yellow flat sheets over face, trunk and skin folds
- Xanthoma disseminatum: numerous small yellow bumps on bilateral face, trunk and skin folds, which may join together to form large flat sheets
- Verrucous xanthoma: scaly white-yellow lesion in the mouth or genital area
If there is an underlying lipid disorders associated with the xanthoma, then metabolic problems such as pancreatitis, atherosclerosis, heart disease, diabetes and obesity can occur. If the xanthoma is associated with underlying blood disorder, then serious blood count problems and other organ dysfunctions may occur.
A skin biopsy may be necessary to confirm the diagnosis. Your Dermatologist/medical practitioner may also order some fasting blood tests, urine tests and x-rays to check for the associated disorders.
For underlying lipid disorders, lifestyle changes including eating healthily and exercise frequently is important. A lipid-modifying medication such as a statin, a fibrate or ezetimibe may be needed. For underlying blood disorders, it will need to be further investigated and managed by a haematologist.
Xanthomas, particularly xanthelasma, that don’t resolve with the above measures, a Skin-based treatment may be needed include:
- Topical Chemical peel, e.g. trichloroacetic acid
- Freezing treatment
- Laser destruction or
- Surgical excision
The outcome of the xanthoma varies considerably between types and would depend on whether the associated underlying cause is optimally managed. Xanthomas may recur after skin-based treatments alone.
This information has been written by Dr Cathy Zhao and Dr Tanumay Raychaudhury