Try to differentiate hand eczema variants

March 1, 2005

New Orleans — Hand eczema is one of the most common work-related illnesses or diseases. But diagnosis is complicated because hand eczema is almost always a group of concurrent reactions (to irritants, allergens and friction) that is exacerbated by the use of water, according to Frances J. Storrs, M.D., professor emerita of dermatology, Oregon Health and Science University in Portland.

New Orleans - Hand eczema is one of the most common work-related illnesses or diseases. But diagnosis is complicated because hand eczema is almost always a group of concurrent reactions (to irritants, allergens and friction) that is exacerbated by the use of water, according to Frances J. Storrs, M.D., professor emerita of dermatology, Oregon Health and Science University in Portland.

Despite the prevalence of hybrid forms, Dr. Storrs feels strongly that every effort should be made to differentiate the variants in order to better outline diagnostic and therapeutic methods. She classifies hand dermatitis as allergic, irritant, atopic, nummular, endogenous, chronic vesicular and frictional or hyperkeratotic - but admits these separations can be imprecise.

Pompholyx and dyshidrosis The greatest confusion, she tells Dermatology Times, is in the endogenous category, which includes pompholyx and dyshidrosis. Physicians tend to use "pompholyx" as a catchall to describe conditions that can't be easily diagnosed. Furthermore, they use "dyshidrosis" interchangeably with "pompholyx."

The cause of pompholyx is unknown. Symmetric vesicles and bullae crop up explosively on non-erythematous palms and, occasionally, on the sides of the fingers and soles. Some patients heal after desquamation. Others may experience a broadening of the eczematous reaction and infection.

"For a patient with pompholyx, I don't patch test. I just treat with systemic corticosteroids for a few days. The problem only presents a few times a year and clears quickly if treated early," Dr. Storrs says.

The closely related condition of dyshidrosis - tiny blisters on normal skin along the sides of the fingers - has a more subtle onset and persists for two to three weeks. Again, Dr. Storrs says there's no point in wasting time with patch testing, although physicians should make sure their patients do not have a fungal condition on the feet, causing a dermatophytid reaction that can mimic dyshidrosis. Corticosteroids can be used for acute dyshidrosis but are seldom necessary.

"If pompholyx and dyshidrosis are defined in this fashion," she says, "these conditions are quite rare."

Hyperkeratotic hand dermatitis Another poorly understood condition is hyperkeratotic or frictional hand dermatitis. Unlike pompholyx and dyshidrosis, this condition does not cause blisters or itching. Generally seen in 40- to 60-year-old males (the primary risk factor is an occupational history as a manual laborer), hyperkeratotic dermatitis presents as a symmetric redness and scaling, and in more severe cases, as fissuring on the palms and soles.

"It's not a chemical irritant dermatitis or an allergy," Dr. Storrs says. "It's probably more related to psoriasis than anything else. You can patch test up the wazoo and won't find anything. Corticosteroids don't help. The only treatments that may help are Grenz therapy and full strength coal-tar solution covered with five percent salicylic acid in aquaphor as well as avoidance of frictional irritants.

Avoid water and friction New treatments for chronic severe vesicular diseases - the hardest hand eczemas to treat - include macrolides, retinoids and vitamin D analogues, but none of the current formulations work very well, Dr. Storrs says.

"My general approach is to tell patients to avoid water, avoid friction and use corticosteroids that are formulated in plastibase or in petrolatum. I also recommend the use of plain Vaseline and triamcinolone or betamethasone ointments when there are flares. For acute contact dermatitis, I don't hesitate to use systemic corticosteroids for a very brief period."

She points out that many common corticosteroid creams contain water, formaldehyde-releasing sensitizers and other common sensitizers. Doctors need to read the contents carefully before prescribing them.

Gloves can be an important part of the treatment paradigm; however, if they are too loose, made with allergic or irritant chemicals, or allow penetration of allergens, they can worsen eczema.