The causes of the disease are unknown. Usually it occurs in women.
Symptoms. Characteristic is the appearance of small, spotted, spotted or spotted-papular elements of round shape from a few millimeters to 1 cm in diameter, dark blue in color. This is due to the effect of Tyndall and is associated with the deep location of melanin in the dermis.
Elements of the rash are usually localized on the face, neck, rear of the hands and feet, buttocks, less often on the mucous membranes.
It is possible to transform into melanoma in old age. Ulceration and bleeding are typical. Sometimes there are multiple eruptive blue nevuses.
Histopathology. In the dermis, fusiform and outgrowth cells containing melanin in the form of large, clearly discernible granules are defined. Proliferation of fibroblast cells.
Treatment. Surgical excision is performed.
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Nevus of Setton
Synonyms: halonews, nevus bordered
Nevus of Setton is a non-celled nevus, surrounded by a depigmented rim.
Causes and pathogenesis. The disease may be based on autoimmune disorders, that is, the appearance of cytotoxic antibodies in the blood and the effect of cytotoxic lymphocytes. In the depigmentation site, a decrease in the melanin content in melanocytes and the disappearance of the melanocytes themselves from the epidermis are noted. It occurs equally often both in men and in women. In a family history, vitiligo is often present.
Symptoms. Before the appearance of the halonovus around the non-vesticular nevus, mild erythema is noted. Then a round or oval lesion is formed - a brown or dark brown papule with a diameter of about 3-5 mm (non-celled nevus), surrounded by a clearly delineated depigmented or hypopigmented rim. Such a halonews is found on any part of the body, but more often on the body. In the future, a non-vesticular nevus may disappear. Halonews can disappear spontaneously.
Differential diagnosis. The disease must be differentiated from a blue nevus, a congenital nevovletochnogo nevus, a nevus Spitz, a primary melanoma, a simple wart and neurofibroma.
Treatment. At an atypical clinical picture and doubts in the diagnosis the nevus is subject to excision.
Synonyms: nevus Spitz, juvenile nevus, juvenile melanoma
The disease occurs at any age. About a third of the patients are children under 10 years old. After 40 years, the disease is rare. 90% of nevi are acquired. There are information about family cases.
The causes and pathogenesis of the disease are unknown.
Symptoms. On the skin of the head and neck there is a papule (or knot) with clear boundaries, round or domed, with a smooth surface devoid of hair, less often - hyperkeratotic, warty. Its dimensions are usually small - less than 1cm. The color of the tumor-like formation is brown, the color is uniform.
With palpation nevus is considered. In rare cases, bleeding and manifestations are possible.
Histopathology. Tumor formation is located in the epidermis and reticular layer of the dermis. There is hyperplasia of the epidermis, proliferation of melanocytes, expansion of capillaries, a mixture of large epithelioid and coarse spindle-shaped cells with abundant cytoplasm, few mitoses.
Differential diagnosis. Nevus Spitz should be distinguished from malignant melanoma of the skin.
Treatment. Surgical excision is performed with obligatory histological examination.
Synonym: Becker-Reuter Syndrome
The causes and pathogenesis of the disease are unknown. Men get sick 5 times more often than women. Possible family cases of the disease.
Symptoms. The disease begins in the puberty period with the appearance of a single plaque with an uneven, slightly warty surface. The color of the lesion from yellow-brown to brown, the color uneven. A large patch of irregular shape, with dentate boundaries, is localized to the skin of the shoulders, back and forearms, under the mammary glands. In the foci of lesion, increased growth of terminal hair is noted. On the part of other organs, shortening of the upper extremities or underdevelopment of the thorax may occur.
Histopathology. Acanthosis, hyperkeratosis, rarely - horny cysts are noted in the epidermis. No nevus cells are detected. The amount of melanocytes is not increased. There is an increased content of melanin in the keratinocytes of the basal layer.
Differential diagnosis. Nevus Becker should be distinguished from the McCune-Albright syndrome and the giant congenital nevokletochnoy nevus.
Treatment. Specific treatment is not.
Causes and pathogenesis. The onset of the disease is associated with disembriogenesis. Family cases are noted.
Symptoms. The disease exists usually from birth: there are oval, linear or irregularly shaped warty, hyperkeratotic papillary formations of different localization, which are often located one-sidedly.
Histopathology. There is hyperplasia of the epidermis, especially of the appendages, sometimes vacuolation.
Treatment. Cryotherapy, electrocoagulation, carbon laser, aromatic retinoids are used.
Synonym: gray-cyanotic gland-maxillary nevus
Causes and pathogenesis. The causes remain unclear. Pathology is considered hereditary. It is inherited autosomal dominantly. Some authors consider Nevus Oto as a variant of the blue nevus. The cup is found in people of Asian descent (Japanese, Mongols, etc.), as well as people of other nationalities.
Symptoms. Nevus Oto can develop from birth or appears in childhood, women suffer more often. The clinical picture of the disease is characterized by a unilateral change in skin coloration in the innervation zone of the first and second branches of the trigeminal nerve (forehead skin, around the eyes, temples, cheeks, nose, ears, conjunctiva, cornea, iris). The color of lesions varies from light brown to gray-black with a bluish tinge. Their surface is smooth, does not rise above the level of the skin. The sclera is often colored blue, the conjunctiva is brown. The boundaries of the hearth are incorrect, unsharp. Vision usually does not suffer. Over time, the color intensity is weakened. Spotted rashes can also be located in the area of the lips. Oral cavity (soft palate, pharynx), on the nasal mucosa. The cases of degeneration into melanoma as a result of irritation of the nevus, a combination with neovus Oto, and bilateral location of the focus are described.
Histopathology. Characterized by the presence of dendritic melapocytes between bundles of collagen fibers.
Differential diagnosis is performed with other pigment nevi.
Treatment. Specific therapy is absent. It is necessary to have a follow-up at the dermatologist and oculist.
Congenital nekvletchetochny nevus
Synonyms: congenital pigmentary nevus, congenital melanocytic nevus
The disease is congenital, although its rare varieties appear during the first year of life. Men and women get sick the same way.
Causes and pathogenesis. Congenital nekvletchetochny nevus occurs as a result of a violation of differentiation melanotsigov.
Symptoms. There are small, large and giant congenital nekvletchetochny nevus localized in any area of the skin. The nevuses to the touch are soft, pliable, their surface is tuberous, wrinkled, folded, lobed, covered with papillae or polyps, reminiscent of cerebral convolutions. The color of the lesions is light or dark brown. The shape of small and large nevuses is rounded or oval, and giant occupies an entire anatomical region (neck, head, trunk, limbs). With age, they can increase in size, possibly the development of perivoneous vitiligo.
Treatment. Given the risk of localization, it is desirable to remove surgically.
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Systematized pigment nevus
Symptoms. Systematized pigment nevi can be congenital or acquired. They can occur in utero and under the influence of various injuries, infectious or other common diseases of the mother.
With the congenital systematized pigment nevus, symmetrical, flattened or slightly raised spots of yellow-brown color, often scattered throughout the skin, appear on the skin level. These spots are sharply delimited from undamaged skin and do not have inflammatory changes along the periphery.
Foci of lesion, sometimes merging, form vast areas of hyperpigmentation with fuzzy boundaries. Most often located on the neck, in the field of natural folds, the trunk. The skin of the face, palms and soles, as well as nail plates are often free from damage. There are no subjective sensations.
Differential diagnosis. The disease should be distinguished from pigmentary urticaria, skin melanosis, acquired lentiginosis and Addison's disease.
The causes and pathogenesis of the disease are unknown.
Symptoms. The comedon nevus is a rare variant of nevi, it is clinically manifested by the lesion, within which there are closely grouped follicular papules slightly rising above the surface of the skin, the central part of which is impregnated with a dense horny mass of dark gray or black. With the forcible removal of the horn plug a deepening is formed, at the site of which there is atrophy.
A nevus is congenital or acquired. The foci often have a linear configuration and can be located in an inferior or bilateral manner. The nevus can appear on any part of the body, including the palms and soles. Foci of lesion are usually asymptomatic, without subjective sensations.
Histopathology. Histologically, comedonic nevi are detected by horny masses filled with invaginations of the epidermis, into the lumen of which the ducts of atrophic sebaceous glands or hair follicles can be opened. A pronounced inflammatory reaction in the dermis is characteristic.
Differential diagnosis. The disease should be distinguished from Mibelli's porokeratosis, papillomatous developmental malformation.
Treatment. Often resorted to electroexcision.
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