Xanthoma | |
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A patient's knee showing multiple xanthoma tuberosum [1] | |
Specialty | Gastroenterology, dermatology |
A xanthoma (pl. xanthomas or xanthomata) (condition: xanthomatosis) is a deposition of yellowish cholesterol-rich material that can appear anywhere in the body in various disease states. [2] They are cutaneous manifestations of lipidosis in which lipids accumulate in large foam cells within the skin. [2] They are associated with hyperlipidemias, both primary and secondary types.[ citation needed ]
Tendon xanthomas are associated with type II hyperlipidemia, chronic biliary tract obstruction, primary biliary cirrhosis, sitosterolemia and the rare metabolic disease cerebrotendineous xanthomatosis. Palmar xanthomata and tuberoeruptive xanthomata (over knees and elbows) occur in type III hyperlipidemia.[ citation needed ]
The term xanthoma stems from Greek ξανθός (xanthós) 'yellow', and -ωμα -oma, a suffix forming nouns indicating a mass or tumor.
A xanthelasma is a sharply demarcated yellowish collection of cholesterol underneath the skin, usually on or around the eyelids. Strictly, a xanthelasma is a distinct condition, being called a xanthoma only when becoming larger and nodular, assuming tumorous proportions. [3] Still, it is often classified simply as a subtype of xanthoma. [4]
Xanthoma tuberosum (also known as tuberous xanthoma) is characterized by xanthomas located over tuberosity of the joints. [2] : 530
Xanthoma tendinosum (also tendon xanthoma or tendinous xanthoma [5] ) is clinically characterized by papules and nodules found in the tendons of the hands, feet, and heel. [2] : 531 Also associated with familial hypercholesterolemia (FH). [6]
Eruptive xanthoma (ILDS E78.220) is clinically characterized by small, yellowish-orange to reddish-brown papules surrounded by an erythematous halo that appear suddenly all over the body, especially the hands, buttocks, and the extensor surfaces of the extremities. [2] : 531 It tends to be associated with elevated triglycerides. [7]
Xanthoma planum (ILDS D76.370), also known as plane xanthoma, is clinically characterized by bands or rectangular plates (macules) and plaques in the dermis spread diffusely over large areas of the body. [2] : 531
Palmar xanthoma is clinically characterized by yellowish plaques that involve the palms and flexural surfaces of the fingers. [2] : 531 Palmar xanthomas are characterised by yellowish to orange, flat macules or slightly elevated plaques, often with a central white area which may be localised or generalised. They often arise in the skin folds, especially the palmar creases. They occur in hyperlipoproteinaemia type III and type IIA, and in association with biliary cirrhosis. The presence of palmar xanthomata, like the presence of tendinous xanthomata, is indicative of hypercholesterolaemia.[ citation needed ]
Tuberoeruptive xanthoma (ILDS E78.210) is clinically characterized by red papules and nodules that appear inflamed and tend to coalesce. [2] : 532 Tuberous xanthomata are considered similar, and within the same disease spectrum as eruptive xanthomata. [5]
Other types of xanthoma identified in the Medical Dictionary include: [8]
Hypertriglyceridemia is the presence of high amounts of triglycerides in the blood. Triglycerides are the most abundant fatty molecule in most organisms. Hypertriglyceridemia occurs in various physiologic conditions and in various diseases, and high triglyceride levels are associated with atherosclerosis, even in the absence of hypercholesterolemia and predispose to cardiovascular disease.
Combined hyperlipidemia is a commonly occurring form of hypercholesterolemia characterised by increased LDL and triglyceride concentrations, often accompanied by decreased HDL. On lipoprotein electrophoresis it shows as a hyperlipoproteinemia type IIB. It is the most commonly inherited lipid disorder, occurring in around one in 200 persons. In fact, almost one in five individuals who develop coronary heart disease before the age of 60 have this disorder.
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment.
Xanthelasma is a sharply demarcated yellowish deposit of cholesterol underneath the skin. It usually occurs on or around the eyelids. While they are neither harmful to the skin nor painful, these minor growths may be disfiguring and can be removed. There is a growing body of evidence for the association between xanthelasma deposits and blood low-density lipoprotein levels and increased risk of atherosclerosis.
A papule is a small, well-defined bump in the skin. It may have a rounded, pointed or flat top, and may have a dip. It can appear with a stalk, be thread-like or look warty. It can be soft or firm and its surface may be rough or smooth. Some have crusts or scales. A papule can be flesh colored, yellow, white, brown, red, blue or purplish. There may be just one or many, and they may occur irregularly in different parts of the body or appear in clusters. It does not contain fluid but may progress to a pustule or vesicle. A papule is smaller than a nodule; it can be as tiny as a pinhead and is typically less than 1 cm in width, according to some sources, and 0.5 cm according to others. When merged together, it appears as a plaque.
Hyperlipidemia is abnormally high levels of any or all lipids or lipoproteins in the blood. The term hyperlipidemia refers to the laboratory finding itself and is also used as an umbrella term covering any of various acquired or genetic disorders that result in that finding. Hyperlipidemia represents a subset of dyslipidemia and a superset of hypercholesterolemia. Hyperlipidemia is usually chronic and requires ongoing medication to control blood lipid levels.
Arcus senilis (AS), also known as gerontoxon, arcus lipoides, arcus corneae, corneal arcus, arcus adiposus, or arcus cornealis, are rings in the peripheral cornea. It is usually caused by cholesterol deposits, so it may be a sign of high cholesterol. It is the most common peripheral corneal opacity, and is usually found in the elderly where it is considered a benign condition. When AS is found in patients less than 50 years old it is termed arcus juvenilis. The finding of arcus juvenilis in combination with hyperlipidemia in younger men represents an increased risk for cardiovascular disease.
Diabetic dermopathy is a type of skin lesion usually seen in people with diabetes mellitus. It is characterized by dull-red papules that progress to well-circumscribed, small, round, atrophic hyperpigmented skin lesions usually on the shins. It is the most common of several diabetic skin conditions, being found in up to 30% of diabetics. Similar lesions can occasionally be found in non-diabetics usually following trauma or injury to the area; however, more than 4 lesions strongly suggests diabetes.
Syringomas are benign eccrine sweat duct tumors, typically found clustered on eyelids, although they may also be found in the armpits, abdomen, chest, neck, scalp, or groin area, including genitals, in a symmetric pattern. They are skin-colored or yellowish firm, rounded bumps, 1–3 mm in diameter, and may be confused with xanthoma, milia, hidrocystoma, trichoepithelioma, and xanthelasma. They are more common in women and are most commonly found in middle-aged Asian women. While they can present at any time in life, they typically present during adolescence. They are usually not associated with any other symptoms, although can sometimes cause itchiness or irritation.
Sitosterolemia is a rare autosomal recessively inherited lipid metabolic disorder. It is characterized by hyperabsorption and decreased biliary excretion of dietary sterols. Healthy persons absorb only about 5% of dietary plant sterols, but sitosterolemia patients absorb 15% to 60% of ingested sitosterol without excreting much into the bile. The phytosterol campesterol is more readily absorbed than sitosterol.
Familial hypercholesterolemia (FH) is a genetic disorder characterized by high cholesterol levels, specifically very high levels of low-density lipoprotein cholesterol, in the blood and early cardiovascular diseases. The most common mutations diminish the number of functional LDL receptors in the liver or produce abnormal LDL receptors that never go to the cell surface to function properly. Since the underlying body biochemistry is slightly different in individuals with FH, their high cholesterol levels are less responsive to the kinds of cholesterol control methods which are usually more effective in people without FH. Nevertheless, treatment is usually effective.
Malakoplakia is a rare inflammatory condition which makes its presence known as a papule, plaque or ulceration that usually affects the genitourinary tract. However, it may also be associated with other bodily organs. It was initially described in the early 20th century as soft yellowish plaques found on the mucosa of the urinary bladder. Microscopically it is characterized by the presence of foamy histiocytes with basophilic inclusions called Michaelis–Gutmann bodies.
Primary cutaneous amyloidosis is a form of amyloidosis associated with oncostatin M receptor. This type of amyloidosis has been divided into the following types:
Granulosis rubra nasi is a rare familial disease of children, occurring on the nose, cheeks, and chin, characterized by diffuse redness, persistent excessive sweating, and small dark red papules that disappear on diascopic pressure.
Perforating granuloma annulare (PGA) is a skin condition of unknown cause, usually appearing on the dorsal hands, presenting as papules with a central keratotic core.
Generalized eruptive histiocytoma is a rare cutaneous condition characterized by widespread, erythematous, essentially symmetrical papules, particularly involving the trunk and proximal extremities.
Xanthoma disseminatum is a rare cutaneous condition that preferentially affects males in childhood, characterized by the insidious onset of small, yellow-red to brown papules and nodules that are discrete and disseminated.
Familial dysbetalipoproteinemia or type III hyperlipoproteinemia is a condition characterized by increased total cholesterol and triglyceride levels, and decreased HDL levels.
The xanthogranulomatous process (XP), is a form of acute and chronic inflammation characterized by an exuberant clustering of foamy macrophages among other inflammatory cells. Localization in the kidney and renal pelvis has been the most frequent and better known occurrence followed by that in the gallbladder but many others have been subsequently recorded. The pathological findings of the process and etiopathogenetic and clinical observations have been reviewed by Cozzutto and Carbone.