Contact allergy (contact dermatitis)

A Contact allergy is also used in medicine as Allergic contact eczema or Contact dermatitis known. All terms mean one and the same disease.

What is a contact allergy?

A contact allergy initially causes skin changes. Within one to three days after contact with the allergen, the skin turns red and swells in the affected area.
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A Contact allergy, allergic contact eczema or Contact dermatitis is an allergic skin reaction that occurs when there is direct skin contact with an allergenic substance (allergen).

Typically, the allergens are substances that the person concerned has to deal with on a regular basis. This can be in the private sector as well as frequently in professional life. Artificially produced substances and natural substances such as plants or parts of plants come into consideration as allergens.

Contact dermatitis does not occur on first contact with the allergen. The formation of the eczema occurs as a delayed reaction of the immune system some time after the contact. In the treatment of contact dermatitis, avoiding contact with the triggering substance is the decisive factor. This often leads to the fact that the previous job or a long-standing hobby can no longer be practiced.

causes

The causes of a Contact allergy are found in hypersensitivity to substances that can cause an allergic reaction through direct body contact. The substances that trigger allergies are different for each person.

Usually, however, it is substances such as flavorings in make-up or commodities, hair dyes and tannins. But cobalt chloride, nickel sulfate, preservatives, cleaning agents, medicines, solvents and plasticizers can also trigger a contact allergy.

But it is not just chemicals that cause contact dermatitis in some people. Plants such as arnica and marigolds, similar to hay fever, can also lead to an allergic reaction.

In women, costume jewelry with nickel components often leads to allergic contact eczema. This is then referred to separately as a nickel allergy. Furthermore, different occupational groups may suffer from contact allergies more often.

Beautician: Solvents, make-up, cosmetics, perfume

Hairdressers: Hair dye, hairspray, hair shampoo

Baker and confectioner: Hypersensitivity to flour

Craftsman: Cement, paints, synthetic resin, adhesives, silicone

Caretaker or cleaning specialists: Cleaning agents, cleaning fluids, room sprays

Symptoms, ailments & signs

A contact allergy initially causes skin changes. Within one to three days after contact with the allergen, the skin turns red and swells in the affected area. Weeping blisters or wheals usually form, which in turn form crusts and scales. This is accompanied by increasing itching and burning.

Long-term contact with the allergen can lead to chronic contact eczema. This forms a cornea that hurts to the touch and can break open after a while. Finally, a chronic skin disease sets in, through which the person concerned permanently suffers from pain, itching and severe discomfort.

In rare cases, the mucous membranes are also affected. Then there is reddening, swelling and rarely ulcers in the area of ​​the mucous membranes. If the respiratory tract is involved, breathing difficulties, swallowing difficulties and acute pain reactions are possible.Occasionally, a contact allergy can lead to an asthma attack.

The symptoms of a contact allergy can appear anywhere on the body. Typically, the hands, face, chest, neck, throat, and ankles are affected. The skin reactions can spread and sometimes affect large areas of the skin. If the allergy is treated early and the allergen is avoided, the symptoms usually subside within a few days.

Diagnosis & course

Schematic representation of the anatomy of the skin as well as the causes and symptoms of allergic skin eczema. Click to enlarge.

The training of a Contact allergy expires in two sections. The first section is called the awareness phase. During this phase, the body comes into recurring contact with the allergen. The exact process and the influencing factors have not been fully researched. What is certain, however, is that the process of sensitization corresponds to the processes involved in defending against infections and that the basis for this is available for every person.

As part of the sensitization, special cells are activated in the lymph nodes, which then multiply. In the second phase, the trigger phase, renewed contact with the allergen leads to the corresponding symptoms.

The skin reactions typical of contact dermatitis usually occur two to three days after renewed contact with the trigger. This shift in time often makes assignment to a specific substance difficult.

With contact dermatitis the same symptoms develop as with other eczema diseases. At the beginning of the disease, the affected area of ​​the skin becomes red and swollen. In the further course, vesicles and nodules, the so-called papules, form. Later the area dries up and scales.

If contact with the allergenic substance is not avoided, the contact allergy can also take the form of chronic eczema. Here the skin becomes coarser and cornifications, so-called hyperkeratoses, and cracks form.

Complications

A contact allergy can lead to various reactions or complaints. As a rule, complications can generally be avoided if the person concerned completely avoids contact with the substance in question. However, this can significantly limit the patient's life and is not always completely possible.

For this reason, the contact allergy often significantly reduces the quality of life of the person affected. This leads to reddening of the skin and itching occurs in different parts of the body. The itching usually increases when the patient scratches the area. Papules can also form, which also lead to reduced aesthetics.

In many cases, the symptoms lead to inferiority complexes or reduced self-esteem. Most patients are ashamed of the symptoms and therefore no longer actively participate in life. By not using a certain ingredient, it can also lead to depression and other psychological complaints.

The contact allergy can be limited with the help of medication. However, complete healing is often not possible. The treatment does not lead to complications and the life expectancy of the person affected is not reduced by the contact allergy.

When should you go to the doctor?

If the typical symptoms of contact allergy reduce the quality of life, a doctor should be consulted. Often symptoms can be avoided by avoiding contact with the triggering substances. Medical advice is needed if the causes of the contact allergy are unknown or if unusual symptoms and symptoms occur. Redness and itching in particular are warning signs that need to be clarified by a doctor. Likewise, pustules and other skin changes as well as shortness of breath, fever and circulatory problems of all kinds.

People who perceive any pustules or redness as cosmetic blemishes should consult their family doctor. Other contact persons are the dermatologist or an internist. An allergist can also be called in. The best way to go to the pediatrician is to go to the pediatrician with children with the symptoms mentioned. Severe breathlessness and serious cardiovascular problems are a medical emergency. The affected person should immediately call the emergency doctor or go to the nearest hospital. If you lose consciousness, the emergency services must be alerted. The contact allergy is then treated in a hospital and the patient is provided with an allergy pass and emergency medication.

Treatment & Therapy

A Contact allergy In acute cases, it is usually treated with ointments containing glucocorticoids. Alternatively, UV therapy can also provide relief. This is mostly used when the patient has other diseases that make the use of glucocorticoids impossible.

The treatment of contact dermatitis is only promising if the allergenic substance is avoided at the same time. The most important thing in the treatment of contact dermatitis is therefore to find its trigger. In some cases there is no improvement in the eczema even after treatment and avoidance of contact with the allergen that is suspected to be the cause.

The prick test is an allergy test, e.g. check for an allergic reaction to pollen or animal hair. Possible allergic substances are dripped onto the skin and then gently pierced with a lancet. After 20 minutes, the reddening of the skin and the size of the wheals are assessed.

It must then be assumed that there are other substances that trigger the allergy. In this case it must be investigated which other substances could be involved. In the case of recurring contact allergies, the cause can be a lack of avoidance of contact with the allergen. In individual cases it is often difficult to avoid the allergen if it is necessary to deal with it almost daily, for example for professional or private reasons.

It is also possible that the symptoms are not due to a pure contact allergy. Sometimes the contact allergy and other allergic reactions or other forms of eczema occur at the same time, which makes diagnosis and treatment difficult.

Outlook & forecast

The chances of finding a complete cure for a contact allergy (contact dermatitis) vary. There may be a cure if the cause of the contact allergy can be determined. If this is the case, professional treatment can take place. In the process, efforts must be made to avoid or eliminate the cause of contact dermatitis. This is often not possible or only possible to a limited extent.

In most cases, contact dermatosis lasts for life. The eczema can be kept in check by giving corticosteroids. In the case of chronic contact allergies, exposure to UV light can be helpful. This can lead to an improvement, especially in the hands. However, since the immune system is involved in contact dermatitis, the prognosis is usually not so positive. Contact with the allergen can often not be avoided completely.

The healing prospects depend on several parameters. If the triggering substance can be kept completely out of life, the contact dermatitis can heal. A contact allergy depends on the presence of the allergen. In the case of work-related contact dermatoses, a change of profession may be advisable or absolutely necessary.

Cortisone ointments may suffice for mild allergy symptoms. In the case of severe and chronic skin dermatoses, the affected skin can become more susceptible to bacterial or fungal attack. It is affected by infections much more often than healthy skin.

prevention

A prevention against the formation of Contact allergies is not possible according to the current state of research. It is never foreseeable which person will react to which substance with the development of contact dermatitis.

Anyone prone to allergies should try to protect their skin with protective gloves and clothing, especially when handling cleaning agents or disinfectants.

The use of pH-neutral products is also recommended. Many allergen-rich products from everyday life, such as soaps, deodorants and fabric softeners, can be replaced by other products. However, the development of a contact allergy cannot be completely ruled out.

Aftercare

The attending physician informs the sick about targeted behavior as part of the initial diagnosis. In addition, it only occurs with acute problems. The patient bears a high degree of personal responsibility for freedom from symptoms. Scheduled follow-up examinations, as is known from tumor diseases, are rare and are related to recurring, serious complaints.

Correctly pinpointing all of the triggers can be time consuming, especially at the beginning. Complications arise when the skin has been damaged for a long time. Often only acute antibiotic treatment will help. Knowledge transfer is a particularly important part of everyday support. The person concerned learns what to do in the event of an allergic reaction.

Ointments and tablets should be available in advance. The best way to avoid the symptoms is to avoid them in the first place. To do this, the patient must bypass the typical triggers or remove them from their surroundings. Aids such as gloves and clothing prevent infections. The patient's actions are decisive for the success of the measures.

You can do that yourself

The best form of self-help for a contact allergy is to identify the allergen and avoid it as much as possible. If finding the cause is difficult, an allergy diary can help. In this diary, the person concerned records his activities and the observed symptoms. The recordings have to be kept for several weeks and then often reveal statistical relationships between a certain activity and an allergic reaction. These evaluations help the attending physician to narrow down the possible allergen.

Allergic reactions to fragrances and other additives in cosmetic products and household cleaners are common. In this case, only care products that are labeled as "hypoallergenic" should be used. There is now a wide range of care products as well as decorative cosmetics that have been formulated with the special needs of allergy sufferers in mind. If you are allergic to cleaning agents, it is usually sufficient to wear gloves when doing household chores.

If, due to a contact allergy, there is a risk that the current job can no longer be exercised, it is extremely important that the patient not only seek medical advice, but also legal advice. A person concerned should contact his trade union or a specialist lawyer for social law as soon as possible. In larger cities, charities often offer free legal advice to people in such situations.