High-Cholesterol Skin Rash: Causes, Treatments, And When To See A Doctor

Cholesterol is a waxy, fatty substance that’s transported through the bloodstream. It can be obtained through animal-based food products, but it’s also produced in the body.

The two main types of cholesterol are:

• Low-density lipoprotein (LDL) cholesterol, which is sometimes called “bad cholesterol”

• High-density lipoprotein (HDL) cholesterol, which is often called “good cholesterol”

Healthy cholesterol levels keep your body functioning optimally. Too much cholesterol can negatively affect your health and increase your risk of developing heart and blood vessel diseases.

Is there a connection between cholesterol and skin disorders?

Researchers¹ have found connections between abnormal cholesterol levels and skin disorders. For example, there’s an association with:

• Xanthomas: bumps on the skin that have fats inside them

• Psoriasis: a skin disease characterized by itchy, scaly patches

• Lichen planus: an inflammatory condition involving swelling and irritation of the skin

• Granuloma annulare: an inflammatory skin rash with raised bumps that form in a ring pattern

There’s evidence the connection between cholesterol and skin disorders goes both ways. While skin disorders aren’t known to affect cholesterol levels, some types of medications used to treat them, such as prednisolone,² could contribute to high cholesterol levels. 

In this article, we’ll focus on the most common high-cholesterol skin rash — xanthomas.

Xanthomas

Xanthomas are the most common skin abnormalities linked to cholesterol levels. These small, raised bumps typically appear on the skin's surface, in the connective tissue. However, they can also grow on tendons and in the subcutaneous layer below the skin’s surface.

Xanthomas are common among older adults and people with high concentrations of lipids in their blood. 

How do xanthomas form?

Xanthomas contain cholesterol and other fats. When fats, such as LDL cholesterol, build up in your blood, they can leak through your capillaries (small blood vessels). As a result, the fats are engulfed by macrophages, a type of white blood cell. When this happens, the macrophages transform into foam cells.

Types of xanthomas 

Xanthomas are categorized based on their appearance and clinical presentation. 

The main types of xanthomas are: 

Eruptive xanthomas 

Eruptive xanthomas are an uncommon type. They’re inflammatory and may be tender to touch. These bumps grow rapidly and are orange or yellow. 

Tuberoeruptive and tuberous xanthomas 

Tuberoeruptive and tuberous xanthomas are similar to one another. They both appear as red or yellow bumps, which may be flat or elevated. Sometimes, tuberous xanthomas merge to form one large mass. 

Tendinous xanthomas 

Tendinous xanthomas feel firm and often have normal overlying skin. They commonly affect the elbows and Achilles tendons. They progress and develop slower than other types of xanthomas. 

Planar xanthomas 

Planar xanthomas are flatter than other types. They typically form on the eyelids or skin around the eyes, appearing as yellow plaques. They can also develop in the creases on the palm of the hand and the surfaces of the fingers and skin folds and are often seen in people with liver cirrhosis. 

Xanthelasma palpebrarum

These are the most common skin xanthomas and are a subtype of planar xanthomas. They’re yellow and flat (or slightly elevated) plaques that form on the eyelids. 

Causes of xanthomas

The direct cause of xanthomas is high cholesterol levels in the blood, which leads to accumulation in the skin. 

Several factors cause high cholesterol; if not adequately managed or treated, high cholesterol levels can lead to xanthomas. 

Genetic conditions

Numerous inheritable conditions cause high cholesterol levels and may lead to the development of xanthomas. 

Familial hypercholesterolemia 

Familial hypercholesterolemia (FH) is an inherited condition that causes high LDL cholesterol and is the main cause of xanthomas in children. FH is specifically associated with tendinous and tuberous xanthomas, which affect around 30% of people with FH.

Cerebrotendinous xanthomatosis 

Cerebrotendinous xanthomatosis³ is a rare metabolic disorder that prevents the breakdown of cholesterol. Impaired breakdown causes cholesterol to be stored in the body and increases a person’s risk of developing tendinous or tuberous xanthomas. 

Familial sitosterolemia 

Familial sitosterolemia is a rare metabolic disorder where people absorb excessive amounts of plant sterols (substances similar to cholesterol but made by plants). This puts people at a greater risk of tendinous or tuberous xanthomas. 

Medical conditions

Numerous medical conditions can cause high cholesterol levels or other fats in the blood, leading to xanthomas. These include: 

• Underactive thyroid (hypothyroidism)

• Chronic kidney disease

• Liver diseases, such as fatty liver or liver cirrhosis (when the liver scars due to blocked bile ducts)

• HIV/AIDS

• Inflammation and swelling of the pancreas (pancreatitis)

• Some cancers

• Type 2 diabetes

• Lipemia retinalis

• Lupus 

In some cases, xanthelasma palpebrarum occurs in the absence of underlying medical conditions. 

Lifestyle factors

Lifestyle factors can lead to high cholesterol levels. In turn, this may increase your risk of xanthomas. 

Some of these lifestyle factors include:

• Being overweight or obese

• Drinking alcohol excessively

• Eating a diet high in saturated fat

• Being sedentary

• Smoking cigarettes 

Medications

Certain medications can make your body store fat and predispose you to develop xanthomas. For example:

• Steroids, such as prednisolone and estrogen replacement

• Sertraline (an antidepressant)

• Oral retinoids

• Protease inhibitors (commonly used to treat HIV) 

High cholesterol isn’t the only factor thought to trigger xanthomas. For example, there’s evidence⁴ that tattooing can cause a Koebner phenomenon, where new xanthoma lesions appear on healthy skin.

Symptoms of xanthomas

Xanthomas are waxy nodules, bumps, or flat patches that develop on the skin, so they’re easy to spot. They can be soft or firm, but firm xanthomas are more common. 

Xanthomas are typically 1–5mm (0.04–0.20in) in size, but in rare cases, they can reach up to 75mm (2.95in). The size depends, in part, on the type of xanthoma. For example, eruptive xanthomas are generally smaller than tuberous xanthomas. 

Xanthomas can form almost anywhere on the skin. However, the most common locations are the: 

• Backs of the arms and legs

• Hands

• Joints, such as the knees and elbows

• Buttocks

• Shoulders

• Eyelids 

Xanthomas may present as single bumps or clusters. Although most often yellow-red, they can be darker. The yellow color is indicative of more fat inside the xanthoma. 

Xanthomas are harmless but may be tender, itchy, and painful.

Treatments for xanthomas

Xanthomas can go away without treatment, especially if they’re small. They generally don’t leave permanent scars. 

Although evidence is limited, researchers believe that:

• Eruptive xanthomas usually resolve within weeks

• Tuberous xanthomas may take a few months to resolve

• Tendinous xanthomas are often more persistent and may take years to resolve

It’s essential to see your doctor about your xanthomas, even if you have no symptoms. Xanthomas can indicate an undiagnosed or poorly-managed health condition and are associated⁵ with an increased cardiovascular risk. 

Treating the underlying medical conditions

Treating the underlying conditions associated with high cholesterol and xanthomas is important to prevent them from forming again. 

• Diabetes: lowering and controlling blood sugar levels, making healthy lifestyle changes, and taking insulin if required 

• Hypothyroidism: taking thyroid hormones to bring thyroid levels under control

• Liver disease: liver transplants and plasmapheresis (the removal, treatment, and return of blood plasma) can lead to the spontaneous disappearance of small xanthomas

• Familial hypercholesterolemia: monoclonal antibodies can lower LDL cholesterol levels to improve xanthomas

Removing the xanthomas

Xanthoma removal is usually done when the xanthomas are large or cause discomfort, but some people have them removed purely for cosmetic purposes. 

After removal, xanthomas can grow back, and if you opt to have yours removed, it’s essential to note that you’ll still need to seek treatment for the underlying medical conditions and other causes of the xanthomas. 

Xanthoma removal methods include:

• Topical treatments, such as trichloroacetic acid (a chemical peeling agent)

• Cryosurgery, which involves using liquid nitrogen to freeze and destroy the cells instantly

• Laser surgery, where the xanthoma is removed using a precisely-calibrated laser

• Surgical excision, which involves cutting the affected tissue 

Xanthomas often grow in areas of the body where wounds heal slowly. This is an important consideration when seeking treatment. Additionally, extra precautions must be taken to ensure adequate wound healing when xanthomas are in areas that may become irritated through close contact with the external environment. 

Medications 

Medications that reduce blood cholesterol levels can help treat xanthomas. Before starting a new treatment, speak with your doctor about the possible risks, benefits, and side effects. Medications that may help with xanthomas include:

• HMG-CoA reductase inhibitors, including statins, to lower cholesterol and help manage hyperlipidemia

• Ezetimibe (Zetia) to reduce the amount of cholesterol in the gut

• Fibrates to reduce triglyceride production in the liver

• Niacin, a form of vitamin B3, to lower triglyceride and LDL cholesterol levels

• Bile acid resins, which bind to cholesterol-containing bile acids, to prevent absorption into the blood and facilitate elimination through the stool

Your doctor may also recommend lipid-lowering antioxidants to improve your lipid levels.

Stopping medications that cause you to store fat may also help treat xanthomas, but check with your doctor first. 

Lifestyle changes to reduce blood cholesterol levels 

Certain lifestyle changes can help reduce cholesterol levels and prevent xanthomas from growing back. 

Recommended lifestyle changes include:

• Exercising

• Maintaining a healthy weight and losing weight if necessary

• Reducing your alcohol intake

• Making healthy dietary choices — avoiding foods high in saturated fat by choosing low-fat or non-fat dairy products, limiting egg yolks, using vegetable fats rather than animal fats, and adding omega-3 fatty acids

When to see a doctor 

See your doctor if you notice any abnormalities or unusual growths on your skin, especially if you have (or have risk factors for) other medical conditions, such as diabetes. While these unusual spots may be harmless (as with xanthomas), they may indicate an underlying condition. 

Seeing your doctor will help you:

• Get treatment to reduce the impact of your xanthomas and minimize the risk of more forming

• Confirm the bumps are xanthomas

• Identify coexisting health conditions of which you may not be aware

• Reduce your risk of developing cholesterol-related complications

Your doctor will carry out several tests and examinations. These may include cholesterol, pancreatic function, liver function, and diabetes tests. 

A skin biopsy, MRI, or ultrasound imaging may be used to confirm if the bumps are xanthomas and not something else, such as tumors or cysts. 

If your primary care doctor feels it’s necessary, they may refer you to a dermatologist (skin specialist).

The lowdown

Xanthomas develop when cholesterol deposits form in the skin because of too much cholesterol circulating in the blood. They’re harmless and most often painless, but they can signify underlying medical conditions that are associated with high cholesterol, such as heart disease, pancreatitis, and atherosclerosis.