Eczema is an inflammatory skin disease often associated with red patches and itching. However, there are other manifestations of eczema. Are joint pains among them?
Joint pain and eczema: Is there a connection?
Eczema: Definition, Causes, and Symptoms.
Eczema is a chronic skin condition characterized by red lesions on the skin surface and intense itching. This disorder is very common, in fact, it is the second most common skin disease, behind acne. Children and infants are the most affected by eczema, and it is estimated that about 17% of 6 - 11 year olds suffer from it. Eczema can be either innate or acquired, depending on its type.
One of the most common forms of eczema is atopic eczema, which is due to a specific genetic predisposition. Individuals with atopic eczema have a skin barrier that no longer fulfills its function, accompanied by a significant permeability of the stratum corneum. This results in substantial water loss and increases the ease with which microorganisms and allergens can penetrate the skin. It is also possible to suffer from eczema without having any genetic predispositions. This is referred to as contact eczema, which is a reaction to a specific allergen in the environment.
Joint pain: definition, causes, and symptoms.
Joint pain affects a large number of individuals. It is estimated that about one quarter of the French population suffers from arthritis. Athletes, people engaged in strenuous activities, and the elderly are most susceptible to this issue. Generally, the areas affected by loss of muscle flexibility are the back, hips, elbows, knees, and hand joints. In general, joint pain manifests during movements that involve a joint. They are a result of the gradual degradation of the cartilage that covers the bone ends of the joints, which leads to pain and stiffness.
At the molecular level, osteoarthritis is characterized by the release of interleukin-1 (IL-1) into the cartilage. This stimulates the production of free radicals, which are involved in theapoptosis of chondrocytes, the resident cells of the cartilage. Interleukin-1 is also responsible for the release of pro-inflammatory prostaglandins, which cause inflammation in the area. Finally, high levels of NGF (nerve growth factor) are observed in patients with osteoarthritis. This growth factor binds to cellular receptors and sensitizes the nociceptive terminals.
A link between eczema and joint pain?
Sometimes, it is assumed that certain joint pains are related to eczema and vice versa. However, even though both of these conditions are caused by inflammation, there is no connection between them. Indeed, eczema is the result of inflammation in the skin, while joint pain originates from inflammation in the joints. Nevertheless, it is entirely possible for a person to suffer from both eczema and joint pain, as these two conditions are not mutually exclusive.
The confusion and supposed link between eczema and arthritis actually stems from a disease called psoriatic arthritis, a specific form of psoriasis that causes joint pain. By analogy, it is sometimes thought that there is also a form of eczema that affects the joints. However, although both eczema and psoriasis are inflammatory skin diseases, they do not cause the same symptoms and should not be confused.
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