<Things you should know> The correct knowledge about "eczema": Explanation of the causes, symptoms, and treatment of "hand eczema" What is hand eczema? Types, symptoms, and causes of hand eczema The mechanism of hand eczema Skin conditions similar to hand eczema How to prevent hand eczema How to treat hand eczema Common problems with hand eczema explained (Q&A) What kinds of eczema can appear on the hands? Even though we refer to it simply as "hand eczema," the treatment methods vary depending on the cause and symptoms. This article, supervised by a dermatologist, provides a detailed explanation of the different types of hand eczema and similar skin conditions. What is hand eczema? Hand eczema is a condition characterized by redness, swelling, blisters, itching, and cracking of the palms, backs of the hands, and fingers. The symptoms can vary widely, appearing as round spots, bumpy rashes, or spreading over a large area.Hand eczema is a general term encompassing various causes, including the loss of the skin's natural oils and moisture-retaining function in the stratum corneum (the outermost layer of skin that prevents external stimuli from penetrating and excessive evaporation of moisture from the body) due to hot water and detergents, developing due to prolonged exposure to chemicals (such as hair dyes, nail polishes, and inks) as a job, becoming sensitive to chemical irritants, and developing the condition due to allergies. Types, symptoms, and causes of hand eczema Hand eczema can be classified into several categories depending on the mechanism of its occurrence and the condition of the skin. Classification based on the mechanism of hand eczema development These can be classified into the following four categories, but it is not uncommon for multiple mechanisms to overlap. irritant contact dermatitis This accounts for 70% of hand eczema cases. It develops due to the high toxicity and irritancy of the causative substance itself.This reaction can occur to anyone, even on their first contact, and is more frequent in individuals with weakened skin barrier function, those in environments or occupations that easily cause skin dryness, or those with atopic dermatitis. The affected area is marked with redness and swelling, and itching is severe. In severe cases, blisters and erosions (where blisters burst and the skin peels off) may develop. Removing the source of contact may alleviate the symptoms.Detergents, cosmetics, chemicals, medicines, foods (meat, fish, vegetables, etc.), plant-derived substances such as tree sap, and friction from clothing and paper are often the causes of irritation.Housewife's eczema, commonly known as "hand roughness," is thought to be a form of contact dermatitis caused by contact with detergents and water. Allergic contact dermatitis After becoming sensitized to a particular substance, an allergic reaction develops upon contact with that same substance. The symptoms are similar to those of non-allergic contact dermatitis, as described above. While almost anything that touches the hands can cause an allergy, common examples include metals such as nickel and chromium, rubber products, ingredients in detergents, shampoos, and hair dyes, and plants (such as poison ivy, primroses, and chrysanthemums). Contact dermatitis to protein antigens This is dermatitis caused by an allergic reaction to allergens that come into contact with the skin. The most common allergens are foods (meat, dairy products, seafood, vegetables, fruits, and spices), but other causes may include animal dander, urine, pollen, and latex.Allergic contact dermatitis is classified separately because its mechanism of allergic reaction is different.Swelling and itching occur in the area that has come into contact with the allergen. The symptoms disappear within a few hours if contact is stopped, but scratching can cause redness, swelling, and peeling of the stratum corneum on the skin's surface. Atopic hand eczema This condition occurs when inflammation caused by acne, insect bites, friction, burns, etc., releases inflammatory cytokines that trigger melanin production, resulting in hyperpigmentation in the affected area. A characteristic feature is that hyperpigmentation occurs after the inflammation subsides. It will naturally fade away by normalizing the skin's turnover cycle. Classification by skin condition In addition to the four classifications mentioned above, skin conditions can also be used for classification. Keratinized hand eczema The keratinized skin on the palms of the hands thickens and peels off in flakes, sometimes resulting in cracks. Similar symptoms are often seen on the soles of the feet. The cause is often unknown, and it is more common in middle-aged and older men. Progressive palmar keratoderma This refers to a type of housewife's (hand) eczema that is characterized by a strong tendency for the skin to harden. Symptoms include dryness and cracking of the fingertips and palms, and loss of fingerprints. Symptoms can appear not only when there is a sudden increase in housework involving water, but also in people whose professions involve heavy physical strain on their fingertips, such as pianists or those who frequently use keyboards. Numb-shaped hand eczema This symptom can occur in irritant contact dermatitis, allergic contact dermatitis, or atopic hand eczema. It mainly appears as coin-sized, circular eczema on the back of the hand, accompanied by intense itching. blister-type hand eczema Small blisters, 2-5 mm in diameter, appear on the palms of the hands and soles of the feet (dyshidrotic eczema). These blisters can then spread to the backs of the hands and fingers due to some irritation, resulting in an itchy, eczematous condition. While it usually heals naturally if the cause is avoided, it can be very difficult to treat for people who use their hands for work or who frequently wash and disinfect their hands. Dry, cracked hand eczema This type of hand eczema is thought to be caused by a weakened skin barrier function and is characterized by dryness and cracking of the palms and fingers, without the formation of blisters. Symptoms often worsen during the winter months. The mechanism of hand eczema It is believed that eczema, including hand eczema, is caused by a complex interplay of external and internal factors. External factors include medications, pollen, chemicals, and bacteria. When these foreign substances enter the skin, the body attempts to eliminate them, triggering an inflammatory response. The degree of this inflammatory response varies depending on internal factors such as health status, sebum secretion, sweating, and the presence or absence of allergies. This mechanism is thought to be what creates the diversity of eczema. Factors that cause eczema Skin conditions similar to hand eczema What skin conditions resemble hand eczema? We will explain below. Palmoplantar pustulosis Palmoplantar pustulosis is a disease characterized by the appearance of numerous pustules (fluid-filled blisters) on the palms of the hands and soles of the feet, which repeatedly improve and worsen. The cause is unknown, but it is more common in smokers. Other contributing factors may include tooth decay, tonsillitis, and dental metal allergies. Tinea manuum Tinea is an infection caused by a fungus called dermatophyte, and symptoms can appear not only on the hands but also on the scalp, feet, trunk, and genitals. Athlete's foot is what is commonly known as "tinea pedis." In the case of hand tinea, the skin between the fingers often peels thinly, or the skin thickens and hardens, sometimes cracking, or small blisters appear. Symptoms may appear on only one hand, and in many cases, athlete's foot is also present. scabies This infection is caused by a mite called Sarcoptes scabiei that infests the skin, and it is accompanied by severe itching, especially at night. Pale red or linear skin lesions, about 2-5 mm in size, appear between the fingers. The mites can also infest the nails, in which case the nails may thicken. psoriasis This condition is characterized by red rashes on the skin, which can occur anywhere on the body. The red rashes are covered with a whitish, scab-like layer of keratin that peels off easily when lightly scratched (scaling). When the red rash appears on and around the nails, it can resemble hand eczema. The nail surface may become uneven, or the nails may weaken and peel off. Candidal interdigital erosion, candidal paronychia This condition is caused by an abnormal overgrowth of Candida, a type of fungus that is normally present in the body. It is often seen in people who work with water. Candidal interdigital erosion causes peeling (erosion) of the skin between the middle and ring fingers, and may be accompanied by itching and mild pain.Candidal paronychia is characterized by redness and swelling around the nail, and pus may be released when pressed. It is difficult to treat and prone to recurrence. How to prevent hand eczema This section explains how to prevent housewife's (hand) eczema.It is important to avoid irritation and prevent dryness. Avoid washing your hands too often, and wear rubber gloves when washing dishes, etc. If rubber gloves cause itching, wear thin cotton gloves over them. Wearing cotton gloves not only when doing housework but also in daily life will reduce irritation. After doing housework or washing your hands, be sure to dry them thoroughly and moisturize with a moisturizing cream.In addition, during the winter months, the air is dry, and exposure to the wind further dries out the skin, so it's important to get into the habit of wearing gloves when going outside.If the eczema is related to allergies, it is necessary to avoid contact with the allergen. How to treat hand eczema If you develop hand eczema, how should you deal with it? The treatment method varies depending on the type of hand eczema, so let's take a look. Irritant contact dermatitis, allergic contact dermatitis The most important thing is to eliminate contact with the substance or allergen that caused the dermatitis. Without doing this, complete recovery will be difficult. In some cases, you may need to consider changing your living environment or occupation. Dermatologists will prescribe topical steroid creams or ointments to reduce skin inflammation, and oral medications to relieve itching if it is severe. Housewife (hand) eczema Even if it heals once, it will recur if you continue the same lifestyle, so it is necessary to make adjustments to your lifestyle to avoid dryness and irritation. As mentioned in the prevention method, wear rubber gloves when doing housework involving water, avoid dryness, and make sure to moisturize with creams, etc. Dermatologists will prescribe topical steroids to suppress skin inflammation, and oral medications to suppress itching if it is severe. Progressive palmar keratoderma Similar to housewife's hand eczema, it is important to avoid external irritants. This includes limiting water-related tasks and wearing gloves. Dermatologists may prescribe topical steroids. blister-type hand eczema If the symptoms are mild and there is no itching, you can manage it with moderate hand washing and applying moisturizer. If you have many blisters and itching, consult a dermatologist and be treated with topical steroids or oral medication to suppress itching. Breaking blisters can cause secondary dermatitis or infection, so avoid irritation and keep the area clean. Avoiding environments that cause your hands and feet to get sweaty and making an effort to wash your hands regularly can sometimes prevent recurrence. Common problems with hand eczema explained (Q&A) This article addresses common concerns regarding hand eczema. Is hand eczema contagious? The conditions listed under "Types of Hand Eczema" are not contagious, but if you scratch and break the blisters, secondary infectious complications may occur, and these complications can be transmitted. Also, tinea manuum, listed under "Skin Diseases Similar to Hand Eczema," is contagious, so if you experience any problems with your hands, do not ignore them or try to self-diagnose them. Please get a diagnosis from a doctor to determine if it is a contagious disease. Is it true that it's prone to recurrence? That's true. Whether it's irritant contact dermatitis or allergic contact dermatitis, if you continue to come into contact with the causative substance in your daily life, recurrences are likely. Housewife's (hand) eczema shows a similar tendency, so it's a good idea to keep your hands moisturized and wear gloves. Supervised by: Dr. Yuki Horiuchi, Director of Akihabara Skin ClinicAfter graduating from the Faculty of Medicine at Tokyo Women's Medical University, she worked at dermatology and cosmetic clinics in Tokyo before opening Akihabara Skin Clinic in 2007. She is a certified specialist of the Japanese Dermatological Association, a director of the Japanese Society for Medical Hair Removal, and an advisor to the A-Care Association. She is a member of the Japanese Dermatological Association, the Japanese Society for Aesthetic Dermatology, the Japanese Society for Laser Medicine, and the Japanese Society for Anti-Aging Medicine, among others. We take care to post accurate information,Please point out any incorrect information. Please submit any comments regarding medical information here. Return to the list of guides categorized by health symptoms.