Hand Dermatitis, or My Hands are Killing Me!
Dr. Sunil Sharon Dhawan has his own private dermatological surgery practice in Fremont and Milpitas, California, and he is a Clinical Assistant Professor in the Department of Dermatology at Stanford University School of Medicine. He received his medical education at the University of Southern California’s Keck School of Medicine.
What is hand dermatitis? Well, it’s any chronic rash on the hands. It is usually symptomatic; it itches, burns, bleeds, irritates, et cetera. About 2 to 9 percent of the general population has it, and a lot of people in my practice and a lot of people in most dermatology practices have it. It is more common in persons with other skin conditions like psoriasis and eczema, and it is especially common among those who work with irritating chemicals. You might often have a mixture of two (or more) of these conditions. For example, a person with atopic dermatitis might also have contact dermatitis. Or someone with psoriasis might develop a fungus infection; you can treat the psoriasis really aggressively but it won’t get better until you scrape it and find out that the person really has a fungus infection and you treat that.
The causes of hand dermatitis are legion, but contact dermatitis is one very common cause. There are two types of contact dermatitis. Irritant contact dermatitis can stem from exposure to chemicals like solvents or from the use of surfactants like soaps and detergents, over-the-counter medications, and even water. Classic allergic contact dermatitis stems from allergies to things like Neosporin, nickel, formaldehyde, hair dyes, certain foods, rubber, and wood-working chemicals. It tends to be more common among people in certain industries such as the cleaning industry, the restaurant and food service industry, and the semiconductor industry, which often exposes workers to epoxy resins.
Contact dermatitis tends to be more common if you have another skin condition such as atopic dermatitis. Though contact dermatitis often affects the hands, it can also affect the face, the arms, and other parts of the body. It tends to be itchy, red, and blistered initially, and then as the skin gets thicker with prolonged scratching, it tends to become less blistery. A classic case of blistering contact dermatitis can stem from exposure to poison oak or poison ivy. Contact dermatitis can appear on either the palm or on the top of the hand; in fact, the whole hand can be occupied with a red, flaky, dry, itchy rash. Of course, a fungus infection can be mistaken for contact dermatitis, and contact dermatitis can also resemble psoriasis, so you can’t always distinguish the exact cause of hand dermatitis by appearance.
How do you diagnose contact dermatitis? Well, you look at a person’s medical history and undertake a physical examination, and you ask the person questions about what they might have come in contact with. You can also do patch testing to see if a person reacts to any of the things people are most commonly allergic to.
Another cause of hand dermatitis is fungal infection. Most commonly you see fungal infection on the nails, on the palm, and on the back of the hand. Often a fungal infection on the hand is associated with infection elsewhere on the body. And you can also have something called an id reaction, which is dermatitis that occurs on one part of the body—usually on the palmar surface of the hands—that is actually a reaction to an infection elsewhere on the body. If we suspect that a fungal infection is the cause of hand dermatitis, we’ll look for infection on other areas of a patient’s body—on their feet, around their toenails, and in the groin, which is a common area to get fungus infections like jock itch. We often will scrape and look at a specimen under the microscope and also culture it, and sometimes, rarely, we will even have to biopsy it in order to make a diagnosis.
Psoriasis is another fairly common cause of hand dermatitis. It’s associated with psoriasis on other areas such as the elbows, knees, and scalp. It can be on either the palm or the top of the hands, and it is generally scaly, red, cracked, and somewhat itchy. It is also often very pustular. As I mentioned previously, sometimes you can have both psoriasis and fungus, and the two look very similar, so you will always need to scrape it and you will often need to do a biopsy.
Atopic dermatitis is also a very common cause of hand eczema, and it is associated with atopic dermatitis elsewhere—on the face, in the bend of the elbows, behind the knee, et cetera. Again, atopic hand dermatitis will be itchy, red, blistered and sometimes scaly. It, too, is very similar in appearance to psoriasis and contact dermatitis. It can be present on both sides of the hands, but I see it more often on the top rather than on the palmar surface. There are many variants of atopic hand dermatitis—nummular eczema, dyshidrotic eczema, hyperkeratotic eczema. A diagnosis is made by looking at a patient’s history, performing a physical examination, taking scrapings and cultures, doing patch tests, and sometimes doing a biopsy.
Treatment for hand dermatitis generally begins with eliminating the triggers. We use topical steroids and topical immunomodulators like Protopic and Elidel. We also make aggressive use of emollients and moisturizers, nonsoap cleansers, and vinyl gloves, and we recommend the avoidance of irritants like soaps and household chemicals. You can use soaks and coverings like cotton gloves or Saran wrap to enhance the penetration and effectiveness of topical steroids; sometimes I recommend that when a case of hand dermatitis is really bad. Avoid using very high-potency steroids for long periods of time because they can cause thinning of the skin. And alternate various steroid strengths and compounds to increase effectiveness and reduce resistance.
Specific treatments differ depending on the cause of hand dermatitis. For contact dermatitis, you try to eliminate the triggers. You treat fungal infections with an antifungal, and you treat not only the hands but other affected areas as well. For psoriasis, you use topical steroids and medications. For atopic dermatitis, you use topical steroids, topical calcineurin inhibitors like Protopic and Elidel, and perhaps tars, which don’t work very well but we do use them sometimes. Also, aggressively avoid soap, use creamy moisturizers, and wear vinyl gloves for all wet work. And avoid occupations where the hands might get irritated.
We do have advanced treatments, which some dermatologist will undertake and some won’t. Some steroids can be taken orally or injected into a muscle. I tend to avoid these, though a local injection of steroids into a very resistant or itchy lesion can be effective. Topical and oral PUVA light treatments for psoriasis and atopic dermatitis work fairly well, but they are cumbersome because people have to go to their doctor twice a week for these treatments. More advanced treatments include oral immune modulators like methotrexate and a multitude of other drugs that I use only rarely. You can use oral Soriatane (acitretin) or biological agents like Enbrel (etanercept) for resistant psoriasis. Soriatane works beautifully for hand psoriasis, especially the pustular type. And of course you can use oral antifungals for resistant fungus infections, especially if the fungus is in the nails.