Hand dermatitis often results from a combination of causes, including your genetics (constitutional factors), injury contact with irritants and allergens. It is frequently caused or aggravated by work, when it is known as occupational dermatitis. Hand dermatitis is particularly common in industries involving cleaning, catering, metalwork, hairdressing, healthcare and mechanical work.
Hand dermatitis varies in severity. It may affect the backs of the hands, the palms or both sites. Often it starts as a mild intermittent complaint, but it can become increasingly severe and persistent. The affected skin initially becomes red and dry, then progresses to itchy papules (bumps) and fluid-filled blisters (vesicles), scaling, cracking (fissures), weeping (exudation) and swelling (edema). Bacterial infection can result in pustules, crusting and pain. Longstanding dermatitis at the ends of the fingers may result in deformed nails. Hand dermatitis can spread to affect other sites, particularly the forearms and feet.
Some people are more prone to hand dermatitis than others. A study in the Netherlands of over 1,900 people between the ages of 30 and 60 reported 10% of women and 4.5% of men had hand eczema. They often have a personal or family history of atopic dermatitis, asthma or hay fever.
Three factors were found to significantly increase the likelihood of hand dermatitis: People with atopic skin, friction or mechanical force, and time to recover or heal from friction or mechanical force.
The most common occupational factor leading to dermatitis is frequent immersion of the hands in water. This is particularly likely if the skin is exposed to detergents (e.g. hairdresers and shampoos) and solvents (e.g. painters and turpentine), as these eventually strip the skin of its natural protective layer. Friction and repetitive injury also damage the skin. Irritants result in much more damage once dermatitis has become established; a few minutes indiscretion can result in a flare-up that can last for several months. Strong acids and alkalis can produce an acute severe reaction.
Sometimes emotional stresses make hand dermatitis worse, especially the type known as pompholyx, dishydrosis or dishydrotic eczema in which crops of very itchy vesicles erupt on the palms, lateral fingers and finger tips.
Allergy refers to specific immunological hypersensitivity: the skin reacts abnormally to a substance that doesn’t affect other people. An immediate reaction is known as contact urticaria; for example some people cannot use latex gloves because as soon as they put them on, their hands become red, swollen and itchy.
Allergic contact dermatitis is a type of hand dermatitis caused by allergy to chemicals or allegens. It can occur hours to days after the contact has occurred, so it can be difficult to identify the cause. There are a huge number of items that can cause allergic contact dermatitis, including nickel, fragrances, rubber accelerators (in gloves) and p-phenylenediamine (permanent hair-dye).
Once a specific allergy has been identified, contact with the causative chemical must be strictly avoided long term to clear up the dermatitis and to prevent its recurrence. One study showed 50% of hand eczema was irritant and 15% was allergic with the remainder being a combination.
If the dermatitis is chronic or extremely bothersome, patch testing can sometimes detect the specific allergens. A dermatologist can perform or arrange for patch tests to distinguish contact allergies from irritant reactions. Patch testing is the only “proof” of an allergen and is valuable in chronic cases of hand dermatitis. It is estimated that 20% of people tested are allergic to nickel. Thus, patch testing is of greatest of value when managing hand dermatitis.
When a strip of specific allergens are applied to intact skin (usually the upper back), the strips are removed in 48 hours. Sometimes an immediate sensitivity is seen. The patient is then brought back 48 hours later (96 hours since the initial visit) and a delayed sensitivity is read.
Irritant contact dermatitis is different from allergic dermatitis as blisters are rarely seen.
Certain Allergens in Hand Dermatitis
Allergic reactions to nickel, dichromate, ethyenediamine hydrochloride, rubber compounds, paraphenylenediamine, and topical preservatives play a significant role in the production and maintenance of hand dermatitits.
Avoidance of nickel-containing objects (jewelry, coins, zippers, buttons and household items) and ingestion of foods containing nickel (chocolate/cocoa powder, cashews, kidney beans, spinach) plays a key role once it has been determined as an antigen.
Chromates (or chromium) are found in tanned leather products, dental implants, construction materials, green dyes in felt and textiles, matches, as well as, foods containing chromate(cloves, thyme, and pepper). Chromates are part of the earth’s crust, and traces of chromates are present in practically all raw materials.
Ethyenediamine hydrochloride (EDD) plays a role in hand dermatitis as it is a substance that is used to manufacture various drugs and industrial compounds. It is a preservative in many medicated creams. It can be found in eye drops, nasal sprays, antifungal creams, antibacterial creams, and many others. Avoidance can be difficult if another family member uses a medication that contains EDD and their medication is transferred to your skin. Pharmacists and veterinarians have occupational risk factors.
Dermatitis to rubber or latex should be suspected especially when hand dermatitis stops at the wrists. Mercaptobenzothiazole and thiram are the most common causes of allergic rubber dermatitis. Rubber finger cots, rubber gloves, rubber bands, hoses, tubing, adhesive tape and bandages should be avoided. Rubber gloves have been found to cause urticaria, eczema, and anaphylaxis due to natural latex proteins. Healthcare workers, pipe fitters and hair dressers are at greatest risk.
Paraphenylenediamine (PPDA) is a derivative of benzene used as a dye for hair, garments, and other textiles. It is also used as a photographic developing agent and in a variety of other processes. PPDA is a strong allergen which can cause contact dermatitis and bronchial asthma. PPDA- positive patch test individuals may have a cross-sensitivity to para-aminobenzoic acid (PABA). Because of this, PPDA –sensitive individuals should use caution with azo dyes incorporated into foods, cosmetics (including hair dye), and medications. Para-aminobenzoic acid (PABA) is a chemical substance that is found in the folic acid vitamin and also in several foods including grains, eggs, milk, molasses, liver and kidney. PABA is also the chemical foundation for a group of local anesthetic drugs such as benzocaine and procaine. PABA was once used in sunscreen manufacturing, but its use now is rarely seen.
Below shows Irritant Hand Dermatitis. Left before and Right after TrueLipids Eczema Experts 1% Hydrocortisone Barrier Cream and TrueLipids Relieve & Protect Ointment 2-4x per day for two weeks.
What is the Treatment?
With careful management, hand dermatitis can be treated. Sometimes taking a few days off work and vacationing, helps with repair. It may be necessary to change professions when severe cases do not resolve.
- Where possible, avoid wet-work and contact with irritants. Nurses, hairdressers, and food handlers are susceptible.
- Protect your hands using vinyl gloves, which are less likely than rubber and latex to cause allergic reactions. Don’t wear these for long periods, as sweating will also aggravate dermatitis.
- Use emollients frequently (like TRUE LIPIDS). A thin smear of a thick barrier cream or ointment should be applied to all affected areas before work, and reapplied after washing and whenever the skin dries out.
- Sometimes a topical steroid is prescribed to reduce inflammation. These come in various strengths and should be applied only to areas of active dermatitis once or twice daily.
- Sometimes hand dermatitis can become secondarily infected and may require a topical or oral antibiotic. In the most severe cases, oral steroids and other modalities are used in conjunction with a chosen treatment regimen.