Congenital aplasia of the skin is a focal defect in the development of the skin, in which the formation of the epidermis, dermis, appendages, and in severe cases of the subcutaneous tissue is disturbed. This state has been known to mankind for more than 250 years, but it has not yet been possible to identify the reasons for its development, there are only theories in this respect in dermatology .
The incidence of congenital aplasia of the skin is not precisely known; most researchers estimate it at a level of 1: 10,000. Sometimes this condition is combined with some genetic diseases and other fetal defects. Congenital aplasia of the skin in most cases does not lead to serious consequences, but the cosmetic defect in the form of a scar in place of the pathological focus remains in humans for life.
Causes of Congenital Skin Aplasia
To date, there is no unified and generally accepted theory that would explain the development of this congenital defect of skin development. It is assumed that the cause of congenital aplasia of the skin is a whole group of various pathological factors that lead to disruption of the neural tube closure process or inhibit the development of embryonic germ of the dermis and epidermis.
Sometimes it is possible to identify the family forms of this condition, with the mechanism of its inheritance, presumably, autosomal dominant. But much more common are sporadic forms of congenital aplasia of the skin, and sometimes in combination with other malformations caused by genetic diseases or exposure to teratogenic factors. This makes it possible to consider this state as a consequence of the influence on the forming fetus of various damaging factors.
Symptoms of congenital aplasia of the skin
Aplasia of the skin is detected immediately after birth. Most often, on the parietal region, there is a center of round shape with a diameter of 1-3 cm. In about a third of cases, two lesions occur, three or more areas of aplasia of the skin occur even less frequently. The pathological area is an erosion or an ulcer covered with a crust and granulations, with no hair covering on it. However, longer and darker hairs grow around the ulcer, which is called the hair collar symptom. The color of the formation varies from pink to bright red.
Over time, in the absence of complications (secondary infection, for example), the area of congenital aplasia of the skin begins to resolve with the formation of a white scar. It also does not grow hair in the future, and it stays with a person for life. In addition to skin symptoms, a child with a focus of congenital aplasia of the skin can be registered violations of the formation of more deeply located tissues and other malformations – cleft lip , cleft palate , eye atrophy. Older children and adults at the site of the scar sometimes can develop malignant neoplasms
Diagnosis of congenital aplasia of the skin
Recognizing this disease is usually not difficult for a dermatologist – its symptoms are quite specific, and it is rather difficult to confuse it with other congenital skin conditions. However, in some cases, other pathological processes and conditions may have a picture similar to congenital aplasia of the skin. Therefore, it is necessary to make a differential diagnosis of this pathology with diseases such as focal scleroderma, discoid lupus erythematosus, as well as the effects of perinatal trauma (from forceps and other obstetric tools). Familial forms of facial skin hypoplasia are very similar to aplasia, however, atrophic foci are observed in the area of the temples.
The most accurate diagnostic data can give a histological study of the tissues of the pathological focus. With congenital skin aplasia, a sharp decrease in the thickness (up to the 1st cell layer) of the epidermis, dermis, and sometimes subcutaneous tissue is observed. Signs of inflammation and leukocyte infiltration (in the absence of a secondary infection) are not observed, and do not reveal skin appendages.
Treatment of congenital skin aplasia
Treatment of congenital aplasia of the skin is conditionally divided into two stages. The first is made immediately after the birth of the child – during this period only preventive and care measures are shown (treatment of erosions with antibacterial ointments, moisturizing agents), dressing to reduce the risk of injury. A few weeks later, a scar will form at the site of the pathological focus, which, although it remains for the rest of its life, can be covered with surrounding hair.
The second stage is reduced to the surgical elimination of the defect (most often, for cosmetic reasons), and it can be done in late childhood or adulthood. When correcting large areas of congenital aplasia of the skin, skin grafts can be used. The prognosis of the disease is generally favorable.
Congenital aplasia of the skin is a group of states of unclear etiology, which are characterized by focal impairment of skin formation with the development of scars. Symptoms of this condition are detected immediately after the birth of a child who has one or more erosions or ulcerations on the scalp or, very rarely, on other parts of the body. Diagnosis of congenital aplasia of the skin is carried out on the basis of examination by a dermatologist, histological examination of tissues in the lesion. Treatment is only symptomatic in order to prevent the development of a secondary infection, but surgical correction of scars is possible to reduce the cosmetic defect.