CONTACT DERMATITIS is a type of inflammation of the skin.
It results from either exposure to allergens (allergic contact dermatitis ) or irritants (irritant contact dermatitis ). Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight. Diagnosis of allergic contact dermatitis can often be supported by patch testing .
* 1 Signs and symptoms
* 2 Causes
* 3 Diagnosis * 4 Prevention
* 5 Treatment
* 5.1 Self-care * 5.2 Medical care
* 6 See also * 7 References * 8 External links
SIGNS AND SYMPTOMS
Irritant dermatitis is usually confined to the area where the trigger actually touched the skin, whereas allergic dermatitis may be more widespread on the skin. Symptoms of both forms include the following:
* Red rash . This is the usual reaction. The rash appears
immediately in irritant contact dermatitis; in allergic contact
dermatitis, the rash sometimes does not appear until 24–72 hours
after exposure to the allergen.
While either form of contact dermatitis can affect any part of the body, irritant contact dermatitis often affects the hands, which have been exposed by resting in or dipping into a container (sink, pail, tub, swimming pools with high chlorine) containing the irritant.
Common causes of allergic contact dermatitis include: nickel allergy
, 14K or 18K gold,
Balsam of Peru (Myroxylon pereirae), and chromium .
Common causes of irritant contact dermatitis include solvents, metalworking fluids, latex, kerosene, ethylene oxide, paper, especially papers coated with chemicals and printing inks, certain foods and drink, food flavorings and spices, perfume, surfactants in topical medications and cosmetics, alkalis, low humidity from air conditioning, and many plants. Other common causes of irritant contact dermatitis are harsh, alkaline soaps, detergents, and cleaning products.
There are three types of contact dermatitis: irritant contact dermatitis ; allergic contact dermatitis ; and photocontact dermatitis . Photocontact dermatitis is divided into two categories: phototoxic and photoallergic.
IRRITANT CONTACT DERMATITIS
Irritant contact dermatitis
Irritant contact dermatitis
Physical irritant contact dermatitis may most commonly be caused by low humidity from air conditioning. Also, many plants directly irritate the skin.
ALLERGIC CONTACT DERMATITIS
Allergic contact dermatitis
Allergic contact dermatitis
Main article: Phytophotodermatitis
Sometimes termed "photoaggravated", and divided into two categories, phototoxic and photoallergic, PCD is the eczematous condition which is triggered by an interaction between an otherwise unharmful or less harmful substance on the skin and ultraviolet light (320–400 nm UVA) (ESCD 2006), therefore manifesting itself only in regions where the sufferer has been exposed to such rays.
Without the presence of these rays, the photosensitiser is not harmful. For this reason, this form of contact dermatitis is usually associated only with areas of skin which are left uncovered by clothing, and it can be soundly defeated by avoiding exposure to sunlight. The mechanism of action varies from toxin to toxin, but is usually due to the production of a photoproduct. Toxins which are associated with PCD include the psoralens . Psoralens are in fact used therapeutically for the treatment of psoriasis , eczema , and vitiligo .
Photocontact dermatitis is another condition in which the distinction between forms of contact dermatitis is not clear-cut. Immunological mechanisms can also play a part, causing a response similar to ACD.
Since contact dermatitis relies on an irritant or an allergen to initiate the reaction, it is important for the patient to identify the responsible agent and avoid it. This can be accomplished by having patch tests , one of various methods commonly known as allergy testing . The top three allergens found in patch tests from 2005–06 were: nickel sulfate (19.0%), Myroxylon pereirae ( Balsam of Peru , 11.9%), and fragrance mix I (11.5%).
The patient must know where the irritant or allergen is found to be able to avoid it. It is important to also note that chemicals sometimes have several different names, and do not always appear on labels.
The distinction between the various types of contact dermatitis is based on a number of factors. The morphology of the tissues, the histology, and immunologic findings are all used in diagnosis of the form of the condition. However, as suggested previously, there is some confusion in the distinction of the different forms of contact dermatitis. Using histology on its own is insufficient, as these findings have been acknowledged not to distinguish, and even positive patch testing does not rule out the existence of an irritant form of dermatitis as well as an immunological one.
In an industrial setting the employer has a duty of care to its worker to provide the correct level of safety equipment to mitigate exposure to harmful irritants. This can take the form of protective clothing, gloves, or barrier cream , depending on the working environment.
Topical antibiotics should not be used to prevent infection in wounds after surgery. When they are used, it is inappropriate, and the person recovering from surgery is at significantly increased risk of developing contact dermatitis.
* If blistering develops, cold moist compresses applied for 30
minutes, 3 times a day can offer relief.
If the rash does not improve or continues to spread after 2–3 of days of self-care, or if the itching and/or pain is severe, the patient should contact a dermatologist or other physician. Medical treatment usually consists of lotions, creams, or oral medications.
* CORTICOSTEROIDS. A corticosteroid medication similar to hydrocortisone may be prescribed to combat inflammation in a localized area. It may be applied to the skin as a cream or ointment. If the reaction covers a relatively large portion of the skin or is severe, a corticosteroid in pill or injection form may be prescribed.
In severe cases, a stronger medicine like halobetasol may be prescribed by a dermatologist.
* ANTIHISTAMINES. Prescription antihistamines may be given if non-prescription strengths are inadequate.
* ^ Mowad, CM (July 2016). "Contact Dermatitis: Practice Gaps and
Challenges.". Dermatologic clinics. 34 (3): 263–7. PMID 27363882 .
doi :10.1016/j.det.2016.02.010 .
* ^ European Society of Contact Dermatitis. "What is contact
* ^ "DermNet NZ: Contact Dermatitis". Retrieved 2006-08-14.
* ^ Gladman A. C. (2006). "
Toxicodendron dermatitis: poison ivy,
oak, and sumac". Wilderness & Environmental Medicine. 17 (2): 120–8.
PMID 16805148 . doi :10.1580/pr31-05.1 .
* ^ Menz, J.; Rossi, ER; Taylor, WC; Wall, L; et al. (1986).
* ^ A B American Academy of
* Sheth, V. M.; Weitzul, S. (2008). "Postoperative topical
* ^ A B C D "