High cholesterol skin warning signs: Identification and significance of seven types of xanthoma

Clinical Manifestations of Hyperlipidemia

Clinical Manifestations: Lipid Deposition in the Dermis Causes Xanthoma

Xanthoma is an abnormal, localized skin protrusion. Its color can be yellow, orange-yellow, or brownish-red, often appearing as nodules, plaques, or papules. The texture is generally soft, mainly due to the accumulation of lipid-phagocytic macrophages in the dermis. Based on morphology and location, xanthomas can generally be classified into the following types:

● Tendon Xanthoma
Tendon xanthoma is a special type of nodular xanthoma occurring in tendons, commonly found in the Achilles tendon, extensor tendons of the hand or foot, rectus femoris in the knee, and deltoid tendon of the shoulder. It is a round or oval, firm subcutaneous nodule, adherent to the overlying skin, with clear borders. This type of xanthoma is often a characteristic manifestation of familial hypercholesterolemia.

● Palmar Crease Xanthoma
Palm crease xanthoma is a linear, flat xanthoma occurring on the palm, appearing as a slightly raised, orange-yellow protrusion, distributed in the creases between the fingers and palm. This type of xanthoma has some diagnostic value for type III hyperlipoproteinemia.

● Nodular Xanthoma: Nodular xanthoma develops slowly and commonly occurs on the extensor surfaces of the body, such as the elbows, knees, finger joints, hips, ankles, and buttocks. It presents as round nodules of varying sizes with well-defined borders. Early on, the texture is relatively soft, but it hardens later due to fibrosis. This type of xanthoma is mainly seen in type III hyperlipoproteinemia or familial hypercholesterolemia.

● Nodular Papillary Xanthoma: Nodular papillary xanthoma commonly occurs on the elbows, extensor surfaces of the limbs, and buttocks. Lesions often appear in batches within a short period, presenting as nodules with a tendency to coalesce. Papillary xanthomas often surround nodular xanthomas. The skin of the lesion is orange-yellow and often has an inflammatory base. This type of xanthoma is mainly seen in type III hyperlipoproteinemia.

● **Papular Xanthelasma:** Papular xanthelasma appears as pinhead or match head-sized, orange-yellow or brownish-yellow papules with an inflammatory base. Sometimes the oral mucosa may also be involved. It is mainly seen in hypertriglyceridemia.

● **Flat Xanthelasma:** Flat xanthelasma, also known as palpebral xanthelasma, occurs around the eyelids and is a relatively common type of xanthelasma. It presents as orange-yellow, slightly raised, flat papules or patches around the eyelids, with clear borders and a soft texture. Widespread cases can involve the face, neck, trunk, and limbs, appearing as flat, pale yellow or brownish-yellow papules, ranging in size from a few millimeters to several centimeters, with clear borders and a smooth surface. This type of xanthelasma is common in various types of hyperlipidemia, but can also be seen in individuals with normal blood lipid levels.

The above-mentioned different forms of xanthelasma can be seen in different types of hyperlipidemia, and patients with the same type of hyperlipidemia may present with various forms of xanthelasma. With effective lipid-lowering treatment, most xanthelasmas can gradually regress.