xanthomas

a papule, nodule, or plaque in the skin due to lipid deposits; it is usually yellow, but may be brown, reddish, or cream colored. Microscopically, the lesions show light cells with foamy protoplasm (foam cells). Xanthomas range in size from tiny pinheads to large nodules, and the shape may be round, flat, or irregular. They are often found around the eyes, the joints, the neck or the palms, or over tendons. Often these lipid deposits are not limited to the skin but are found throughout the body in bones, the heart, blood vessels, liver, and other organs.



The formation of xanthomas may indicate an underlying disease, usually related to abnormal metabolism of lipids, including cholesterol. Abnormally high levels of blood lipids may be found in diabetes mellitus (xanthoma diabeticorum), in diseases of the liver, kidney, and thyroid gland, and in several hereditary metabolic diseases. The excessive lipids carried in the blood may then be deposited as xanthomas. Treatment includes surgery, application of acids directly to the lipid deposits, and management of the disease that causes them.