Most common causes of contact dermatitis revealed

Published 12:00 am Tuesday, March 14, 2006

By Adam Hammer, Tribune Features Reporter

A recent study performed by the Mayo Clinic in Rochester reveals the most common causes of allergic contact dermatitis, a skin inflammation resulting in swollen, reddened and itchy skin.

Dermatitis can have many causes and there are several different types. It is not life threatening or contagious, but it can make people feel uncomfortable and self-conscious.

Contact dermatitis is common among all age groups and can cause minor annoyance to more severe handicaps, according to Dr. Mark Davis, a Mayo Clinic dermatologist and lead study researcher.

&8220;Patients with contact dermatitis can get a very itchy rash from head to toe, or in a confined area,&8221; Davis said in a press release from the Mayo Clinic. &8220;If it’s on the hands and feet it can be disabling and patients at times can’t do their jobs.&8221;

Contact dermatitis results when one’s skin comes into contact with an allergen or irritant. In some cases, blisters and weeping sores may be present.

The chief treatment for contact dermatitis is avoidance of allergens, according to Davis. At times corticosteroid creams are used to treat rashes, however, about 3 percent of patients with contact dermatitis are allergic to the topical steroids that would alleviate their symptoms.

The Mayo study found that the top 10 causes of contact dermatitis were:

– Nickel (nickel sulfate hexahydrate), a metal frequently encountered in jewelry and clasps or buttons on clothing.

– Gold (gold sodium thiosulfate), a precious metal often found in jewelry.

– Balsam of Peru (myroxylon pereirae), a fragrance used in perfumes and skin lotions, derived from tree resin.

– Thimerosal, a mercury compound used in local antiseptics and vaccines.

– Neomycin sulfate, a topical antibiotic common in first aid creams and ointments. It is also found occasionally in cosmetics, deodorant, soap and pet food.

– Fragrance mix, a group of the eight most common fragrance allergens found in foods, cosmetic products, insecticides, antiseptics, soaps, perfumes and dental products.

– Formaldehyde, a preservative with multiple uses such as paper products, paints, medications, household cleaners, cosmetic products and fabric finishes.

– Cobalt chloride, a metal found in medical products and also hair dye and antiperspirant. Cobalt chloride can also be found in objects plated in metal such as snaps, buttons or tools and in cobalt blue pigment.

– Bacitracin, a topical antibiotic.

– Quaternium 15, a preservative found in cosmetic products such as self-tanners, shampoo, nail polish and sunscreen or in industrial products such as polishes, paints and waxes.

Sometimes, the most important part of treatment is the proper diagnosis. A biopsy may be necessary for proper diagnosis or patch testing may be ordered.

The Mayo study determined that patch testing with a series of substances is useful for identifying common contact allergens. Patch testing is conducted by placing potential allergens, covered with patches, on patients’ backs for two days. After two days, doctors observe which substances cause skin irritation.

The study confirmed previous findings by the North American Contact Dermatitis Group.