Nummular eczema is a form of eczema that can affect individuals at any age. Its symptoms are often mistaken for those of other skin conditions, such as psoriasis and fungal infections. To identify nummular eczema, follow our advice.
An overview of nummular eczema.
Nummular eczema, also known as discoid eczema, is a form ofeczema typically localised on the arms, legs, and buttocks. It is often a specific case of atopic dermatitis, meaning it is linked to an atopic genetic predisposition. The skin barrier of individuals suffering from this condition allows water to evaporate easily and allergens to penetrate, due to a low level of filaggrin and other proteins essential for the integrity of the stratum corneum. Furthermore, affected individuals secrete large amounts of immunoglobulin E (IgE) in response to environmental antigens, causing intense immune reactions to common allergens.
It also happens that nummular eczema can occur in individuals who are not genetically predisposed to this type of condition. In these non-atopic individuals, meaning those whose skin barrier does not exhibit any dysfunction, the etiology of nummular dermatitis is unknown.
The symptoms of nummular eczema.
Nummular eczema, sometimes referred to as discoid, is characterised by the emergence of rounded patches of oval or circular shape, clearly defined on the skin. These red patches, which resemble coins in appearance, have a diameter between 1 and 5 cm. The term "nummular" actually comes from the Latin "nummus" which means "coin". Nummular eczema, like other types of eczema, evolves in flare-ups. Another indicator of nummular eczema is the presence of blisters on the red patches. When these rupture, they ooze and form crusts which subsequently turn into scales.
The location of the red patches is another good indicator of nummular eczema. Indeed, the lesions caused by this dermatosis are primarily located on the legs, arms, and buttocks. Less commonly, they appear on the chest or back. The skin lesions due to nummular eczema cause intense itching and can also be painful. The symptoms of this skin condition impair the quality of life of those who suffer from it. Indeed, the itching and pain lead to sleep disturbances. The oozing caused by the bursting vesicles also promotes the social isolation of the patients.
The diagnosis of nummular eczema must be carried out by a healthcare professional who conducts a clinical assessment for this purpose. They first examine the appearance of the skin lesions and pay attention to their distribution, which is quite characteristic in the case of nummular eczema. Furthermore, a medical consultation also allows the identification of the origin of the eczema: atopic or contact. In the case of contact eczema, patch tests are used to determine the allergen responsible for the reaction and to eliminate it from the daily life of the affected person. This subsequently allows to prevent recurrence of nummular eczema.
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