Epidermal nevus is a malformation of the skin that originates from melanocytes. The abnormality is benign and is also known as a birthmark. Excision may be performed if cosmetic impairment occurs.
What is an epidermal nevus?
Nevus are circumscribed skin and mucosal malformations of a benign nature and usually originate from pigment-producing melanocytes. Brownish-stained nevi of melanocytes are also referred to as pigment nevi. Colloquially, they are referred to as moles or liver spots. Epidermal nevi are moles of the epidermis. The epidermis corresponds to the uppermost, keratinizing layer of skin epithelium and carries neither nerves nor vessels. Epidermal nevi usually manifest as striated, often brownish thickenings of this skin layer. This is usually accompanied by hyperkeratosis, i.e. keratinization of the squamous epithelium. The epidermal nevus shows a high prevalence. Instead of the spelling “nevus” the medical literature also uses the spelling “nevus”. From the epidermal nevus in the form of an isolated appearance is to be distinguished the so-called syndrome of epidermal nevus (ENS). This is the association of epidermal nevi with developmental disorders of nerves, skeleton, urogenital tract and cardiovascular system. Various subtypes of epidermal nevus exist, some of which are associated with additional syndromes.
Causes
Epidermal nevi usually originate from melanocytes. These are the pigment-forming cells of the skin that are found primarily in the epidermal basal cell layer. The cells produce melanin, which absorbs teratogenic UV radiation and protects those in deeper skin layers from degeneration. Melanin production is mainly related to the level of melanocyte-stimulating hormone. This is a cleavage product of proopiomelanocortin. In addition, vitamin D metabolites and stimuli such as UV radiation play a role in production. Moles can be congenital or acquired. The causes of congenital epidermal nevi have not yet been conclusively clarified. A genetic predisposition is assumed for both congenital and acquired forms of epidermal nevus. Also disorders of the immune system and environmental influences or hormonal causes are discussed as causal factors for nevi. The development of moles is always a complex process, shaped by internals such as genetic predisposition and favored by various externals.
Symptoms, complaints, and signs
Epidermal nevi may be present from birth. Usually, they develop during childhood at the latest. The epidermal nevus is sharply demarcated and manifests as a cobblestone-like, scaly or verrucous thickening of the epidermal skin layer. In isolated cases, itching is reported. Different forms of epidermal nevus are distinguished. The circumscribed variant corresponds to a soft, striated, verrucous change of the skin. This variant is more commonly associated with itching than the other variants. In addition, a well-known form of epidermal nevus is the purely verrucous form, which is accompanied by signs of inflammation. In addition to pruritus, this variant may present with linear or hemispheric systemic spread of the skin lesion. This form in particular occurs almost exclusively in childhood. The spread usually occurs at a low rate. In isolated cases, dystrophy of the nails has been observed in patients with this type of epidermal nevus.
Diagnosis
The diagnosis of epidermal nevus is initially made by visual diagnosis. In congenital forms, the skin abnormality is noticed immediately after birth. However, epidermal nevi are most commonly diagnosed in childhood. Like all other moles, the malignancy of the changes must be ruled out by histology. Differentially, psoriasis and licher ruber must be considered. Histopathologically, the epidermal nevus appears as acanthotic thickening of the epidermis, usually associated with hyperkeratosis. In patients with pruritus, lymphocytic infiltration of the dermal skin layers may also be observed. The prognosis is excellent for patients with isolated epidermal nevus. There is usually no risk of degeneration.
Complications
An epidermal nevus is referred to as a dermatologic malformation. The mostly congenital anomaly originates from the pigment cells of the skin and has benign characteristics. Colloquially, the symptom is known as a birthmark or mole. The epidermal nevus shows itself in a stripy to blotchy as well as beige-colored expression. At times, the affected skin layer is speckled dark brown and slightly thickened. Depending on the manifestation, there is keratinization of the outer and inner organ surface of the skin at this point. The symptom may develop subtypes over the years, some of which vary with other clinical pictures. In addition to the congenital birthmark, there are variants which occur due to immune disorders, environmental factors or hormonal. Usually, an epidermal nevus is free of complications. However, some birthmarks may be accompanied by severe itching, resulting in scarring. As a concomitant to the symptom, affected individuals may have malgrowth of the nails. The actual complication is more cosmetic. If the birthmark is located in the visible area of the head, neck or décolleté, it is considered disturbing, especially if it becomes unattractively keratinized, raised or considerably scarred. In this case the skin lesion is removed. If the lesion is too pronounced or symptoms recur, the procedure may need to be repeated.
When should you go to the doctor?
If there are changes in the general appearance of the skin, a doctor should be consulted. If the skin blemishes spread or increase in intensity, it is advisable to consult a doctor. In case of itching or an unpleasant skin sensation, a visit to the doctor is recommended. If open wounds develop, they should be treated sterilely. If this cannot be ensured to a comprehensive degree, medical wound care should be sought. Germs can enter the organism via the open areas on the body, which can lead to further illnesses. In severe cases, there is a risk of blood poisoning and thus a life-threatening condition. A doctor should be consulted in good time as soon as malaise, fever, dizziness or a general feeling of illness develop. If there is skin discoloration, swelling or inner restlessness, a doctor should be consulted. If emotional as well as mental impairments occur due to the changed skin appearance, a visit to the doctor is necessary. In case of social withdrawal, reduced well-being, shame or a depressive mood, it is advisable to contact a doctor or therapist. If there are behavioral problems, sleep disturbances or reduced performance, a doctor is needed. If the affected person wishes to have the skin abnormalities removed, he or she should seek contact with a surgeon and obtain comprehensive information about the cosmetic procedure and its options.
Treatment and therapy
Because epidermal nevus is often congenital and thus appears to be largely due to genetic factors, no causal therapy exists. Symptomatic treatment is possible but not mandatory. Symptomatic treatment measures are used in the context of skin abnormality, for example, when the patient perceives the birthmark as a cosmetic nuisance. In addition, symptomatic therapy may be useful in cases of more or less severe itching. Patients with itchy nevi are advised not to scratch their mole. Since itchy skin lesions may affect the quality of life of patients to a greater or lesser extent, excision is often suggested to the affected individuals in this case. Excision is an invasive treatment model. In the procedure, the mole is surgically removed by a dermatologist. Smaller nevi can be removed within minutes under local anesthesia. For facial epidermal nevi or larger nevi, a plastic surgeon usually performs the excision. After complete removal, the surgeon usually performs aesthetic defect closure in this case. The defect closure is usually performed by local skin displacement, especially in the face. In case of large changes in the epidermis, serial excision is performed. Thus, the removal takes place in repeated procedures, stretching the surrounding skin piece by piece using skin expanders. The resulting defect is finally compensated with the stretched skin.
Outlook and prognosis
The prognosis of epidermal nevus is favorable. It is a benign change in skin appearance that does not normally show mutations over the lifespan. Although the skin change is genetic and therefore there is no causal therapy, the epidermal nevus is in most cases without a medical disease value. Treatment is usually only required if the affected person feels an emotional suffering due to the visual conspicuousness and sees a need for action. In the case of complications such as itching or a psychological impairment, removal of the skin change is performed in a routine surgical procedure. The procedure is performed locally and is completed within a few minutes. Once the subsequent process of wound healing is complete, the patient can be discharged from treatment as symptom-free. In rare cases, irregularities in scar formation occur. These worsen the favorable prognosis, as do unexpected disturbances in the wound healing process. While laser treatment can significantly improve scarring, irregularity in wound healing carries the risk of sepsis. This has a potentially life-threatening course and must therefore be treated by a doctor as quickly as possible and receive intensive medical care. Delayed medical treatment will result in premature death of the patient due to sepsis.
Prevention
Epidermal nevus cannot be completely prevented to date. Avoidance of stimulating stimuli such as UV light and control of hormone balance usually helps only in moderation if a genetic disposition is present.
Aftercare
In this disease, the measures of aftercare are very limited or even impossible. However, they are usually also not necessary if the disease does not need to be treated.First and foremost, a quick and, above all, early diagnosis is very important in order to treat the disease properly and to classify the symptoms accordingly. An independent cure cannot occur with this disease, so that the affected person is always dependent on a medical examination. Since this disease can also cause significant impairment of aesthetics, those affected are not infrequently dependent on psychological treatment. In this context, intensive and loving conversations with one’s own parents or friends are very useful, and contact with other affected persons can also be useful in this context. If the symptoms are removed by a surgical procedure, the wound should be protected after the procedure to prevent infection. Likewise, follow-up checks are very important to ensure that healing also proceeds without discomfort. Usually, this disease does not reduce the life expectancy of the affected person and no further measures of a follow-up are necessary.
What you can do yourself
In any case, an epidermal nevus should be clarified by a physician and then treated if necessary. Symptomatic therapy is not mandatory, but action should be taken against the individual symptoms to avoid serious complications. Strict hygiene measures help with itching. The affected skin area is best protected from irritating influences such as skin care products or cold. Special remedies from natural medicine alleviate the discomfort. For example, an ointment made from chamomile extract applied directly to the skin lesion has proven effective. If further skin changes occur, there may be a serious underlying cause that must first be found and remedied. If a hormonal disorder is the cause, hormone therapy may have to be administered. In most cases, however, it is sufficient to change one’s lifestyle and reduce stress, for example. A healthy and balanced diet is also effective in treating hormonal disorders, as well as disorders of the immune system. If the symptoms are due to a vitamin D deficiency, the substance must be replenished through the diet. If these measures show no effect, the epidermal nevus should be taken to the doctor again.
