A convex birthmark is formed due to pathological changes in the skin (cell proliferation, resulting in a built-up or compacting of the skin of a certain radius). Sometimes the birthmark can contain pigments of melanin, giving it a color of a darker shade. Melanin is synthesized in the presence of melanocyte cells due to exposure to ultraviolet radiation. It should be noted the role of melanotropic hormone, produced by the pituitary gland. Therefore, in the process of pigmentation of moles, not one body system is involved.
The main causes are the presence of some factors - local developmental defects, hereditary predisposition, ultraviolet radiation, hormonal failure in the body, trauma, infection and viruses.
Local causes of developmental defects
It is about birthmarks of an innate nature, which in 60% of cases are the cause of pigmented spots. In this case, a convex birthmark appears as a result of a violation of the correct division of cells during the last periods of pregnancy. In general, such a defect in the birth of a child is not noticeable. And only after 2-3 years the new formation manifests itself in a visual examination.
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Factors of heredity
At the moment, one can not exclude the occurrence of birthmarks due to hereditary pathologies of the skin. Tumor neoplasms and moles are initially encoded in certain genes in the molecule of deoxyribonucleic acid (DNA). This genetic chain is transmitted by the chromosome to the children from the parents.
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Nevuses arising from exposure to ultraviolet radiation
The growth of melanocytes in the basal layer of the skin is stimulated by ultraviolet radiation. With increased insolation, the number of melanocyte cells will increase. Thus, if you want to get a dark tint of skin (tan), resulting from the normal response of cells to the effects of sunlight, there is a danger of pathological changes in the cells of the epidermis and dermis. The appearance of such convex moles is inherent in adults, and has acquired character.
Medical observation of patients with convex birthmarks showed that hormones actively participate in the formation of nevi. According to the results of the research, it was noted that most often birthmarks of acquired character appear in adolescents during the maturation of the reproductive system of the body. Also at risk are people who have serious disruptions in the endocrine system. In rare cases, the appearance of tumors affects women during pregnancy. The main reason is the effect of hormonal adjustment of a pathological or physiological character on the functions of the pituitary gland. In these cases, the prognosis of the disease is favorable, since such birthmarks are small in size and can disappear themselves after a while.
Injuries, bacteriological infections and viruses
The traumatic factor of the formation of nevi (mechanical damage, insect bite) refers to minor and rare causes. In this case, the main role is played by the inflammatory process in various layers of the skin. As a result of inflammation, biologically active substances are formed, which stimulate the growth of cells. A similar mechanism of formation has convex birthmarks, resulting from the entry into the body of infections of viral and bacterial etiology. It should be noted that when a person is infected with the papilloma virus, the formed convex birthmark is different in nature. Therefore, from the point of view of histology and dermatology, it is classified as a papilloma, and not a nevus.
The above-mentioned factors of the appearance of convex moles allow us to determine the risk group. This includes people who are predisposed to the appearance of moles. Particular danger consists of convex birthmarks, prone to develop into malignant tumors.