What is Allergic Dermatitis?
Allergic dermatitis is a disease that develops as a response of the patient’s body to the effects of an optional stimulus (that is, a substance that does not develop allergic reactions in normal healthy people) by direct contact with the skin for even a relatively short time.
In such cases, it is customary to say that the body of the patient has become hypersensitive, or sensitized, with respect to the substance, which, since the onset of the disease, becomes an allergen for a particular patient. Moreover, sensitization is quite specific and develops, as a rule, with respect to only one particular substance or group of substances similar in chemical structure.
Causes of Allergic Dermatitis
Allergic dermatitis is inherently an allergic reaction of a slow-acting organism, i.e. an allergy itself forms for a sufficiently long period of time, with very long contact of the organism with an irritant. Allergic reactions in these cases are not mainly involved antibodies, but specific immune cells, mainly lymphocytes. Therefore, when a material obtained from a pathological focus is examined under a microscope, a very characteristic feature is always revealed: large accumulations of immune cells that have left the bloodstream and have moved to the pathological focus. Allergens for the body of the patient often become various chemical compounds.
These are mainly different types of laundry detergents, insecticides, chromium, nickel and their compounds. There are a lot of allergens among drugs and cosmetics: syntomycin emulsion, ointments with antibacterial drugs, various dyes for hair dye, etc. The allergen itself cannot often cause an allergic reaction, as it has very small sizes, as a result it is not recognized by immune cells organism. However, when it enters the bloodstream, it enters into a relationship with blood proteins that are large enough. As a result, the resulting compounds begin to play the role of allergens. Of particular importance in the formation of contact allergies, i.e. allergies as a result of direct contact of the irritant with the skin, has recently been attached to phagocytic cells that are located directly in the skin layers.
These cells have the ability to absorb and digest allergens and immune complexes in the skin (an allergen chemically bound to an immune protein). Already after only a few hours after the application of the appropriate allergen to the skin of a sensitive person, their number is able to increase by several orders of magnitude. At the same time, all allergens are adsorbed on the surface of phagocytes and are associated with them. In addition, phagocytes are able not only to digest allergens, but also to facilitate their contact with specific immune cells, as a result of which a developed immune response occurs in the patient’s body. With repeated hits of allergens into the body to the place of their introduction, a huge number of already existing, “familiar” with them immune cells and antibodies rush.
An allergic reaction occurs much more violently than the first time. In turn, the substances secreted by these cells contribute to an even greater penetration of phagocytes and lymphocytes into the inflammatory focus. These substances are also responsible for the general protective reactions of the skin: the development of edema, dilation of blood vessels and redness, increased itching, etc.
Symptoms of Allergic Dermatitis
In many ways, the clinical manifestations of the disease resemble those during the acute stage of eczema. At the very beginning, rather large spots of redness appear on the skin, against the background of which tiny bubbles begin to form. They are multiple, after they burst and emptied, leaving in place their constantly moist surface defects of the skin. Small scales and crusts can also be produced in large quantities.
The main lesion is always located exactly in the place where the allergen affected the skin. However, any allergic reaction, not excluding allergic dermatitis, is not a disease of a separate organ or area of the body, but of the whole organism, therefore, secondary lesions can appear absolutely anywhere on the body. Mostly they are small nodules, areas of edema, vesicles, reddening spots. These foci may be located on the skin very far from the place of direct action of the allergen.
For example, with a disease that develops as an allergic reaction in response to the use of mascara, redness spots can be so large that they seize the skin in the face, neck, and shoulders, and sometimes much lower. In the overwhelming majority of cases, all the rash on the skin is accompanied by complaints from the patient to persistent intense itching, which interferes with daily life, night sleep, sometimes causing the patient very severe pain.
Diagnosis of Allergic Dermatitis
In most cases, the diagnosis of the disease is fairly easy to make by analyzing the data obtained during the examination of the patient and with careful examination of his skin. Manifestations of an allergic reaction in all cases are quite characteristic and specific to the allergic type of dermatitis. Currently, for the final confirmation of the diagnosis, various skin allergy tests have been widely used.
These research methods allow not only to clarify the diagnosis, but also to identify specific allergens, in response to the action of which the disease itself has developed. Their essence is that with the help of syringes, solutions of various most frequently encountered allergens are injected into the patient’s skin. Ordinary sterile water is also added to control. After some time, at the sites of administration of substances for which there is an allergy, a reddening spot appears with a portion of skin edema. There should be no pathological manifestations at the site of water injection. Such studies are mandatory for examining patients in production, as they allow to identify production allergens, to give such a patient recommendations for further work. The only condition is that these samples should be carried out only after all skin manifestations of the disease have been eliminated.
In some situations, an allergic variety of dermatitis has to be distinguished from the initial stages of eczema and toxicoderma (see below). With eczema, the body is allergic to many types of stimuli, while with allergic dermatitis it is only to one specific one. Also, with eczema, all skin manifestations develop for a very long time, while with dermatitis, they occur within seconds from the time of exposure to the allergen. Sometimes it is necessary to distinguish the disease from toxicoderma, with the latter, the irritants are not applied directly to the skin, but are ingested with food or other ways inside.
Treatment of Allergic Dermatitis
Treatment of allergic dermatitis is carried out according to the results of the examination. A dermatologist after determining the allergen selects an individual effective therapy. For the treatment of atopic dermatitis, local and general desensitization therapy is actively used, and a hypoallergenic diet is selected.
Folk treatment of dermatitis, unlike professional medical, does not lead to recovery.