There are many different causes of hand eczema, both exogenous and endogenous. It is important to find the exact cause to get rid of the contact dermatitis of the hands.
Most cases of hand eczema have multiple causes. Atopy, dry skin, constant exposure to allergens, a tendency to seborrheic dermatitis, incessant rubbing or scratching all can potentiate the original cause and sustain the hand eczema.
Exogenous Causes for Hand Eczema
- Contact irritants: These produce hand eczema through contact irritant dermatitis. The severity of eczema depends upon the concentration of the irritant and period of exposure. Examples for contact irritants causing hand eczema are: Chemical irritants like soap, detergents, garlic, lemon and solvents; and physical causes like friction, minor trauma, cold dry air etc.
- Contact allergens: Contact allergens produce hand dermatitis in individuals who are already sensitized to these antigens. Contact allergens produce allergic contact dermatitis of the hands through two types of immunological responses. One is through the delayed type of hypersensitivity reaction (Type IV), as seen with chromium, nickel and rubber allergies. The second one is the immediate type of hypersensitivity reaction (Type I), as occurs in the sudden itchy eruption of the hands following ingestion of sea food in sensitized individuals.
- Phototoxic Contact Dermatitis: Lemon juice, cement, nickel etc. can cause severe bullous type of hand eczema following exposure to sunlight. Many irritant and allergic plant juices also cause such phototoxic contact dermatitis.
- Ingested allergens: From food, drugs, possibly nickel and chromium in food items.
- Infections: A secondary infection of a wound on the hands can become eczematous if not treated promptly. The bacterial proteins act as antigens to produce the inflammatory skin changes.
- Secondary dissemination: A secondary ide eruption caused by a fungal infection in a remote area like the feet can cause tense, itchy or painful eruptions on the hands.
Endogenous Causes for Hand Eczema
- Idiopathic. Most of the time, vesicular, discoid or hyperkeratotic hand dermatitis with painful fissures appear without any apparent cause. These are called idiopathic hand eczema.
- Immunological: Immunological or metabolic/genetic defects can be the cause for hand eczema, as is seen in atopic dermatitis.
- Psychosomatic: Stress can induce, aggravate and maintain hand eczema, as it does in most other eczemas. Stress plays an important role in conditions like pompholyx or dyshidrotic hand eczema.
- Dyshidrotic: Increase sweating of the palms or palmar hyperhidrosis can cause eczematous dermatitis on the palms.
Other Diseases Mimicking Hand Eczema
Major conditions that mimic hand eczema are:
- Palmar Psoriasis: Thick hyperkeratotic scaly plaques with painful fissuring can occur in psoriasis, this may resemble chronic hand eczema. Psoriatic plaques elsewhere on the body, on the soles etc. will clinch the diagnosis. When it is limited to the palms, a biopsy may be required for definite diagnosis.
- Tinea manum or ring worm of the hands: Itchy rounded scaly skin patches involving both the palms and back of hands (sometimes limited to one side) can cause confusion in diagnosis of hand eczema. Scraping the scales and examination under microscope after dissolving in potassium hydroxide 10% solution will clinch the diagnosis of fungal infections of the hand.
- Candidal intertrigo: Commonly seen in housewives and hair dressers, candidal infection of the finger web spaces may look similar to contact dermatitis. Satellite lesions in the periphery and a positive potassium hydroxide microscopy will help in differentiating the yeast infection from hand eczema.
It is evident from the above discussion that finding the exact cause and differentiating between different types of hand eczema are of paramount importance to get rid of the hand eczema.
Reference
Disclaimer
The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or suite101 will not be responsible for any consequences. The images provided are for illustration purpose only.
The copyright of the article Causes of Hand Eczema in Eczema is owned by Hanish Babu. Permission to republish Causes of Hand Eczema in print or online must be granted by the author in writing.
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