Environmental dermatology
When a person suffers from an onagain off-again rash that they can’t seem to find any explanation for, they go to see a dermatologist. Dermatology is, after all, the study of the skin and its diseases. However, not all dermatology is the same and there are some specialties that are more suited to special cases than others. The range of dermatology is diverse and varied. It’s important to see the right specialist to get the best and fastest treatment for your particular skin problem.
For example, a rash that appears and disappears may be caused by an external factor like an allergy. It’s possible that the skin problem is triggered by something in the environment. This type of rash or skin problem is referred to as “contact dermatitis” and is handled by a specialist in Environmental Dermatology.
Environmental Dermatology is a specialized branch of dermatology that specifically handles the evaluation and management of skin diseases related to the environment, particularly dermatitis or eczema that may be caused when a patient is exposed to a chemical in the environment that is causing an allergic reaction or a recurring rash like contact dermatitis.
Contact dermatitis is a localized rash or skin irritation that is caused by exposure to an allergen or irritant in the environment. There are two different types of contact dermatitis. The first is Irritant Contact Dermatitis. This type of contact dermatitis is an inflammation that is caused by the exposure of an irritating substance (like an acid or an alkaline substance) to the patient’s skin in a high concentration for a certain amount of time. This type of contact dermatitis does not involve the patient’s immune system.
The second type of dermatitis is known as Allergic Contact Dermatitis. This is common and happens when susceptible skin is exposed to particular chemicals called allergens. These allergies occur through hypersensitivity (oversensitivity) to a substance and involve the patient’s immune system. Areas of the skin that are exposed to the allergen will react to it by developing itching and redness, even blisters. Once the allergen is removed the rash will eventually disappear.
When a patient gets a rash, they usually go to see their dermatologist or their internist. However, when a regular dermatological checkup can find no cause or explanation for the rash, the patient is referred to environmental dermatology to run an almost weeklong patch test and see if the answer can be found in something the patient has been exposed to.
Patch testing is a diagnostic test that reproduces the dermatitis by applying small amounts of different types of allergens to the patient’s skin under adhesive tape (patches). These are usually placed on chambers that are then taped to the back of the patients and left for 48 hours during which time they must stay dry. After the first 48 hours the patient returns to the doctor to have the patches removed and read. After an initial reading, the patient is requested to return the next day or two days later for the 2nd reading. This can usually tell the physician which chemicals the patient is allergic to. From there, the patient and doctor can determine what is causing the rashes.
Through patch testing and investigation into a patient’s lifestyle and work, a solution can usually be found to their dermatitis. Once the patch test tells the physician what chemicals the patient is allergic to it is only a matter of finding out how they are being exposed to the allergen so they can avoid it. It can sometimes be difficult but avoiding the allergen is the only way for this type of dermatitis to disappear. One common allergen and ranked number one in allergy causing substances is nickel sulfate. This can be found in almost everything that has metal: rings, pens, belt buckles, earrings. These things alone are not usually enough to cause the irritation but if the substance begins leaking nickel sulfate the allergic reaction can and will occur.
The hands are usual sites that a person develops rashes since the hands are the most common body part that touches almost everything. This is common in manufacturing plants and other companies. Industrial workers tend to develop contact dermatitis from overexposure to chemicals on their job for example, masons develop allergen contact dermatitis from exposure to cement day in and day out. Occupational dermatology, working hand in hand with environmental dermatology, helps determine allergens in the workplace thereby helping prevent dermatitis on the job.
Many people don’t realize that these reactions (rashes, irritations, or other such skin disorders) can be fixed and even avoided if patients just knew what was causing them. Through environmental dermatology patients can better their lives by knowing what substances and chemicals to avoid or to substitute when possible. Identifying allergens in the workplace not only makes it safer for the workforce, but keeps them healthier and more productive as well and a patch test allows patients to be more aware of themselves and their environment.
At the St. Luke’s Dermatology Center, patients can get one of the most comprehensive patch tests available in the country with up to 70 different allergens. This gives patients a broader range and a wider chance of finding the correct allergens. In addition to patch testing, St. Luke’s also conducts photo patch testing, which determines whether an allergy is caused not only by an allergen but by the allergen’s exposure to sunlight as well.
The St. Luke’s Dermatology Center’s Environmental Unit offers patch testing and photo-patch testing. The environmental dermatologist and the patch test nurse at the St. Luke’s Dermatology Center are skilled, trained and motivated to assist patients in the management of contact dermatitis. After tests have been conducted and allergens are determined, the Center provides patients with a comprehensive list of substances they are allergic to including all known names for the substance, where it is commonly found, how to avoid it, and what substitutes they can try. This helps patients avoid what they are allergic to thereby preventing future dermatitis. After a positive patch test, patients are requested to follow up in a month to see how they have been successful in avoiding the allergen from their environment. This allergen avoidance strategy should reflect on the clearing of their dermatitis and relief from their onand-off itchy skin problem.
Dr. LONABEL A. ENCARNACION is Head of the St. Luke’s Dermatology Center in Quezon City and concurrently heads the Environmental Dermatology unit of the Center. She was trained in patch testing and photo patch testing at St. Luke’s- Roosevelt– Columbia Presbyterian College of Physicians & Surgeons in NYC, NY, USA. She is currently a faculty member of the St. Luke’s College of Medicine- William H. Quasha Memorial. She is a regular speaker on Occupational Dermatology for the Philippine College of Occupational Medicine. She is also a member of the Philippine Dermatological Society Board of Directors. For inquiries, please contact the St. Luke’s Dermatology Center in Quezon City at 7230101 ext. 5208 and in Global City at 7897700 ext 2083.