Introduction
Emily C. Milam and David E. Cohen Irritant Contact Dermatitis 15
Synonyms: Irritant reaction Irritant dermatitis Irritant dermatitis syndrome Irritant contact dermatitis syndrome Toxic contact dermatitis “Irritation” “Chemical burn”
Key features
Irritant contact dermatitis (ICD) is a localized, non-immunologically initiated, cutaneous inflammatory reaction. Its clinical characteristics are polymorphous and include erythema, scaling, edema, vesiculation, and erosions in acute cases, with erythema, lichenification, hyperkeratosis, and fissures in chronic cases
ICD results from a direct cytotoxic effect due to single or repeated application of a chemical substance or physical insult to a cutaneous site
ICD is a common disorder and represents an important spectrum of clinical presentations in both general and occupational dermatology, occurring when the normal epidermal barrier is disrupted and secondary inflammation develops
Despite different pathogeneses, allergic contact dermatitis and
ICD have similar clinical appearances, especially their chronic variants
ICD is a multifactorial syndrome determined by the properties of the irritating substance as well as host and environmental factors; a dose–response relationship is related to exposure parameters such as concentration, pH, temperature, occlusion, repetition, and duration of contact
Strong or absolute irritants such as strong acids and alkalis, as well as oxidants, produce erythema, edema, vesicles that may coalesce into bullae, oozing, and, in severe cases, necrosis and ulceration. The latter is vernacularly termed a “chemical burn”
ICD is most often caused by cumulative exposure to weak irritants such as soap and water
The clinical features of chronic ICD from repeated exposure to low-grade or marginal irritants (e.g. soaps, solvents, cleansers, weak acids and bases) include erythema, lichenification, excoriations, scaling, and fissures