Eczema is a so-called pruritic (itchy) dermatosis which is characterized by non-contagious inflammation of the skin and which is accompanied by redness, fine blisters and itching. This eczema can appear very early in life since it is seen even in infants. It is characterized by periods of flare-ups during which the symptoms worsen interspersed with periods of remission or the damage to the skin and the itching regress.
Eczema is often associated with asthma or various allergic reactions. Among all the skin diseases, eczema is the most frequent skin disease since in industrialized countries it affects 15 to 30% of children and up to 10% of adults. In addition, recent studies have shown that these eczema cases have doubled in the past 30 years. So why ?
The mechanism of eczema is not yet well understood: it affects both the immune system and the skin cells that act as a barrier for allergens. A component of genetic heredity is proven but the presence of environmental factors such as chemical irritants or stress would influence the appearance of eczema.
Several hypotheses have been put forward to explain this upsurge in eczema cases and in particular the change in infant eating habits. Indeed, the early introduction of diversified foods at the expense of breastfeeding would lead to very early exposure to food allergens while the infant’s immune system is still immature. This would be especially true for one of the forms of eczema called atopic eczema. This is because there are many different types of eczema and the term eczema is often a generic name used regardless of the type of variant of the disease. There are three types of eczema: atopic eczema, contact eczema and seborrheic eczema.
What is atopic eczema?
Atopic eczema is the most common form of chronic eczema which occurs in 90% of cases before the age of 5 and which even appears very often in infants. Atopy is the tendency to react with allergic reactions to contact with normally harmless allergens such as dust, pollen, animal hair, etc.
People with atopia often have various other allergic reactions, such as hay fever, hives, asthma or food allergies, simultaneously or alternately. There is very often a hereditary component since this atopic eczema is observed in families where at least one of the members suffers from it.
In babies, this eczema mainly affects raised areas such as the cheeks, scalp, shoulders, thumb when it is put in the mouth, while in children over 2 years old it is mainly the folds of the elbows. , wrists and knees folds that are affected. In adolescents, it is always the flexion folds but also around the eyes or the soles of the feet and in adults: the neck, ankles, feet and hands.
What is contact eczema or contact dermatitis?
Contact eczema, also called contact dermatitis, is an irritation of the skin on contact with products such as cosmetics ( for the bath, shower, face, body ) but also on contact with saliva, sweat or even metals (nickel for jewelry or coins). This eczema can have an allergy mechanism or quite simply activate on contact with an irritant substance. The reaction is then immediate or appears within a few hours after contact. Symptoms may vary depending on the nature of the product being used and the intensity of sensitization to simple redness up to ulceration. The diagnosis to determine the offending substance is made by a doctor a few times using skin patches.
What is seborrheic eczema?
Seborrheic eczema is manifested by the appearance of fatty, yellowish and scaly patches that form on the skin but most often on the scalp, even in infants. It causes a very serious problem of dandruff in adults and this eczema can spread to the face, the wings of the nose, the ears or even the chest. At the level of the plaques, we note the presence of a fungus of the Malassezia type which is a normal host of the skin.
How does eczema progress?
Depending on the type of eczema, symptoms can last for one to two weeks or last for years as regular attacks. Good news: atopic eczema generally appears before 18 months but it decreases most of the time during childhood to disappear in 70% of cases at the beginning of adolescence with some possible relapses, however, in adulthood.
Complications of eczema
If the eczema patches are scratched, they will ooze, become more irritated and can sometimes become infected. It is then possible to contract:
- – A bacterial superinfection in particular due to a staphylococcus which can cause an impetigo with the appearance then of yellowish crusts on the lesions of eczema.
- – Cellulitis which results in a sudden onset of swelling on the skin in a place affected by an eczema lesion. This area then becomes very sensitive, red and hot.
In these 2 cases, it is imperative to consult the best skin doctor in south delhi very quickly or to seek advice from your pharmacist who will then refer to the doctor if necessary. Beyond the irritated red patches that itch and flakes, the evolution of eczema can eventually lead to thickening of the skin, which can become drier, lose its hairiness and eventually change in pigmentation.
Eczemas: what are the causes and origins?
The causes and risk factors of atopic eczema
The occurrence of atopic eczema is often linked to a family history since approximately 50 to 70% of children with atopic eczema have a first-degree relative (father, mother, brother, sister) who has had it themselves. . In fact, atopic eczema results from both genetically transmitted immunological and skin abnormalities. These anomalies in the structure of the skin transmitted by genes allow allergenic molecules to penetrate the epidermis and be in contact with skin immune defense cells which are activated in an exaggerated manner, then causing an inflammatory reaction: ‘eczema.