Hand eczema is a type of dermatitis and eczema that occurs in the hands. It is also called hand dermatitis. The annual incidence rate in China is about 7.3% to 11.8%, and in foreign countries it is 6.5% to 17.5%. It is a common dermatological disease. . The etiology of this disease is complicated, mostly caused by contact with allergic substances or irritants, and can also be caused by genetic atopic constitution. The disease manifests complex and diverse. In the acute phase, there may be erythema, papules, blisters, erosions, and in the chronic phase, hyperkeratosis, peeling, and cleft palate may be seen. Both hands are in frequent contact with the outside world in daily life, and any change in factors can cause changes in the condition, which makes the hand eczema often complicated and chronic, and the treatment is more difficult.
Hand eczema is often caused by a variety of endogenous or exogenous factors. Allergic substances and irritants in the external environment are the main causes of the disease, such as heavy metals such as nickel, chromium and cobalt contained in pigments or ornaments; preservatives, aromatic compounds contained in cosmetics and detergents; and even low irritating water. Or oily substances can cause disease in case of repeated exposure for a long time. In addition, physical damage to the skin such as rubbing and scratching is also an important cause of the disease. At present, it is believed that exogenous factors mainly destroy the skin barrier and reduce the defense ability of the epidermis in the pathogenesis of hand eczema. When the skin’s defense power is reduced, external irritants, sensitizers, and pathogens are more likely to invade the skin, further destroying the skin’s repairing ability and barrier function, thereby causing a vicious circle.
In addition to the influence of the external environment, many endogenous factors also play an important role in the development of hand eczema. The most common factor is atopic physique, which accounts for about 22% to 37% of all hand eczema patients. Other factors include hormone levels, medications, mental status, immune status, smoking, and more. Therefore, in the patient visit, you should ask the medical history in detail to find all possible causes.
2. Classification of diseases
At present, there is no uniform classification standard for hand eczema, which is mainly classified according to the cause and shape. The common types are as follows:
1). Classification of causes
Irritant contact dermatitis (ICD):
This type is an inflammatory reaction of the skin caused by repeated exposure to irritants (low toxic substances) for a long period of time. Symptom severity is usually positively correlated with stimulant dose and contact time. Most patients have experience with wet water (contact with soap or solvents) or long-term use of closed gloves, so they are more common in housewives. This type of diagnosis is usually based on the history of exposure to the relevant stimuli, and a patch test is required to rule out contact allergies.
Allergic contact dermatitis (ACD):
This type is mostly T-lymphocyte-mediated contact delayed type allergy, mainly for chemical substances, especially nickel and chromium. Patients with symptoms such as erythema, blisters, and itching that are rapidly exposed to proteinaceous substances are called protein contact dermatitis (PCD) or contact urticaria, and are more common in chefs, butchers, etc. This type needs to be confirmed by a patch test.
Atopic hand eczema (AHE):
Patients often have a history of asthma, hay fever or atopic dermatitis. Due to impaired skin barrier, this type of patient is susceptible to external irritation and ICD occurs. Allergen prick test and serum IgE test are helpful in diagnosing AHE.
Mixed type and undetermined cause:
Some patients have multiple causes at the same time, called mixed hand eczema. Another 20% of patients do not have the above-mentioned causes, which are unidentified hand eczema. For these patients, morphological diagnosis is often used (see below).
2). Morphological classification
Keratinized hand eczema: more common in middle-aged and elderly people, mainly in the localized clear keratinized plaque, often dry, peeling, and sometimes see crack-like changes with pain. This type is easily confused with psoriasis, but erythema is less common and there is no scaly lesion or nail change typical of psoriasis.
Recurrent blister-type eczema:
Manifested as a large amount of blister in the palm with itching, often repeated attacks. In severe cases, it can involve the soles of the feet and explode blistering, which can be called bullous eczema. Such hand eczema has nothing to do with sweat gland function, and it is necessary to distinguish it from sweat herpes. Contact allergic reactions or atopic hand eczema may also be manifested as the same vesicular rash; in this case, the cause classification is preferable.
It is a blistering disease that can affect the palms and toes. It is related to abnormal sweat gland function, also known as sweating bad eczema. Typical skin lesions are miliary vesicles scattered or clustered in the palm of the hand, which are not easily broken, and peeling can occur after absorption of the blister fluid. It is high in spring and summer, and it can heal itself after the weather turns cold.
Also known as discoid eczema, mainly expressed in the back of the hand and finger rounded coin-sized erythema, common herpes, edema, exudate and scarring. The rash can gradually enlarge and affect other parts of the body. The course of disease is slow and easy to relapse.
Or chronic fingertip dermatitis, characterized by dry, cleft palate, scaly damage to the fingertips, and pain in severe cases. It is usually caused by long-term chronic stimulating of the fingertips leading to sebum deficiency, which is common in the office population.
Impaired skin barrier function is the central link in the pathogenesis of hand eczema. It is the key to successful treatment to remove pathogenic factors and strengthen skin repair. All patients should use emollients for a long time and use gloves properly at work and in life. Moisturizers should be selected from safe products that do not contain fragrances and preservatives to prevent irritation. In addition, proper vitamin and trace elements are also beneficial to the repair of the skin barrier.
2). Topical drugs
Topical corticosteroid cream is a first-line treatment. Hormone types should be selected based on the severity of the symptoms. Patients with mild symptoms and short course of disease can use weak hormones such as hydrocortisone; if the symptoms are slightly heavier, you can choose intermediate hormones such as triamcinolone acetonide; for severe chronic hypertrophic eczema, you can choose betamethasone and halomethasone. To super-potent hormones, keratinolytic agents may be added if necessary, or combined with laser introduction or encapsulation to promote drug absorption. Hormone application time should not be too long. It is generally recommended that the continuous application of potent hormones should not exceed 2 weeks. For chronic severe eczema with severe symptoms, it should not exceed 8 weeks. If the symptoms improve, the dosage should be changed to 2-3 times per week. .
Topical calcineurin inhibitors also have a certain effect on the eczema of the hand. These drugs are prescribed for external use of hand eczema, but in recent years they have been widely used in the treatment of dermatitis and eczema diseases, especially for atopic dermatitis, so it is especially suitable for AHE patients. When other types of hand eczema require long-term treatment, these drugs can be selected as a supplement.
Other topical drugs may be used according to specific conditions. For example, if there is a large amount of exudation in the acute phase, it may be wet-coated with ethacridine or boric acid solution; when the erosion is damaged with a small amount of exudation, zinc oxide paste may be used; when combined with infection, external antibacterial preparations such as 100 may be used. DuPont, clotrimazole cream, etc.
3). Phototherapy and local radiotherapy
UVA1, UVA/UVB and narrow-spectrum UVB have a good effect on moderate to severe chronic hand eczema. Shallow X-rays can be used for severe chronic hand eczema that is difficult to treat, especially for hyperkeratotic hand eczema.
4). System medication
The role is more limited. For patients with severe acute phase, short-term (