Allergic contact dermatitis,

Finally structure activity approaches have recently been developed to identify contact sensitizers. This approach is based on the concept that the biologic mechanisms that determine a chemical s effect are related to its structure and hence chemicals with similar structures will have similar effects. Computer models have been developed to compare the structure of an unknown chemical to structures in a database for known 

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Eye and Skin Contact. Some nickel salts and aqueous solutions of these salts, eg, the sulfate and chloride, may cause a primary irritant reaction of the eye and skin. The most common effect of dermal exposure to nickel is allergic contact dermatitis. Nickel dermatitis may occur in sensitized individuals following close and prolonged contact with nickel-containing solutions or metallic objects such as jewelry, particularly pierced earrings. It is estimated that 8—15% of the female human population and 0.2—2% of the male human population is nickel-sensitized (125). 

There are hundreds of topical steroid preparations that are available for the treatment of skin diseases. In addition to their aforementioned antiinflammatory effects, topical steroids also exert their effects by vasoconstriction of the capillaries in the superficial dermis and by reduction of cellular mitosis and cell proliferation especially in the basal cell layer of the skin. In addition to the aforementioned systemic side effects, topical steroids can have adverse local effects. Chronic treatment with topical corticosteroids may increase the risk of bacterial and fungal infections. A combination steroid and antibacterial agent can be used to combat this problem. Additional local side effects that can be caused by extended use of topical steroids are epidermal atrophy, acne, glaucoma and cataracts (thus the weakest concentrations should be used in and around the eyes), pigmentation problems, hypertrichosis, allergic contact dermatitis, perioral dermatitis, and granuloma gluteale infantum (251). 

They are unlikely to prevent an allergic contact dermatitis. 

Allergic contact dermatitis Skin condition that occurs in response to exposure to sensitizing material. It is characterized by redness, swelling and cracking and, sometimes more severe reactions involving the entire immune system. 

Allergic contact dermatitis, burning, dryness, edema, irritation... 

Dermal Effects. Based on a skin patch test, allergic (contact) dermatitis to methyl parathion occurred in a farmer (Lisi et al. 1987). 

Jessner s Solution has been used for over 100 years as a therapeutic agent to treat hyperkera-totic epidermal lesions [1]. This superficial peeling agent constitutes a mixture of salicylic acid, resorcinol, and lactic acid in 95% ethanol. Jessner s solution causes loss of corneocyte cohesion and induces intercellular and intracellular edema. Jessner s typically induces wounding to the level of the papillary dermis. Historically, resorcinol (a key component of Jessner s peels) was used in concentrations of 10-50% in the early twentieth century. High concentrations of resorcinol were associated with side effects such as allergic contact dermatitis, irritant contact... 

Complications of hydroquinone therapy include acute and chronic reactions. Common acute reactions are irritant and allergic contact dermatitis, and post-inflammatory hyperpigmentation. Lesional and perilesional hypopig-mentation may occur. This is usually a tempo-... 

PIH can be observed after endogenous or exogenous inflammatory conditions. Essentially any disease with cutaneous inflammation can potentially result in PIH in individuals capable of producing melanin. Several skin disorders such as acne, atopic dermatitis, allergic contact dermatitis, incontinenti pigmenti, lichen planus, lupus erythematosus, and morphea have PIH as a predominant feature. Exogenous stimuli,both... 

Some nickel compounds may be irritant to skin and eyes and dermal contact with nickel can result in allergic contact dermatitis. Nickel carbonyl is extremely toxic by inhalation and should be handled in totally enclosed systems or with extremely efficient ventilation. Air monitors linked to alarms may be required to detect leaks. Respiratory equipment must be available for dealing with leaks. Biological checks (e.g. nickel in urine) should be considered for routine operations involving nickel catalysts. 

Skin contact with metalworking fluids may cause skin irritation or a contact irritant dermatitis. Contact with neat oils may cause folliculitis (oil acne). Contact with some aqueous-mix fluids may, depending upon the additives, e.g. biocides, cause an allergic contact dermatitis. Formerly the use of unrefined mineral oils posed a risk of skin cancer. 

Irritant contact dermatitis results from first-time exposures to irritating substances such as soaps, plants, cleaning solutions, or solvents. Allergic contact dermatitis occurs after an initial sensitivity and further exposure to allergenic substances, including poison ivy, latex, and certain types of metals. 

FIGURE 62-5. Allergic contact dermatitis of the hand chromates. Confluent papules, vesicles, erosions, and crusts on the dorsum of the left hand in a construction worker who was allergic to chromates. (From Wolff K, Johnson RA. Eczema/ dermatitis. Fitzpatrick s Color Atlas Synopsis of Clinical Dermatology. 5th ed. New York McGraw-Hill, 2005 27.)... 

The allergic form can take several days to present and the condition may extend beyond the borders of the region exposed. Allergic contact dermatitis may also include oozing pustules and skin erosion. 

Allergic contact dermatitis is a delayed hypersensitivity reaction.30 Upon initial exposure, a substance penetrates the skin, binds to a protein and develops into sensitizing antigens. Subsequent exposures to that substance will then elicit an allergic reaction.25,29,30 Symptoms of allergic contact dermatitis are similar to those of the irritant type, but may take several hours to several days to develop following re-exposure.25,26... 

In contrast, nothing is known about B megapotamica and its relationship with other plants in its habitat. However, both P. hysterophorus and B megapotamica pose a serious hazard to animals who ingest these plants. P. hysterophorus has been implicated in allergic contact dermatitis common in many parts of India (11,12), and, as we shall see, B megapotamica contains a series of sesquiterpenes which are probably the most potent skin irritants known. 

Camarasa JG, Serra-Baldrich E. 1992. Allergic contact dermatitis from triphenyl phosphate. Contact Dermatitis 26 264-265. 

Side effects include dryness, irritation, and allergic contact dermatitis. It may bleach or discolor some fabrics (e.g., clothing, bed linen, towels). 

Side effects include skin irritation, erythema, peeling, allergic contact dermatitis (rare), and increased sensitivity to sun exposure, wind, cold, and other irritants. 

Grabbe, S. et al., Dissection of antigenic and irrative effects of epicutaneously applied haptens in mice. Evidence that not the antigenic component but non-specific proinflam-matory effects of haptens determine the concentration-dependent elicitation of allergic contact dermatitis, 7. Clin. Invest., 98, 1158, 1996. 

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