Irritant Contact Dermatitis

ICD-11

EK02

Synonyms

Irritant contact dermatitis (ICD), cutaneous irritation, irritant dermatitis, irritant contact eczema, toxic dermatitis, "wear and tear" dermatitis, Friction dermatitis.

Epidemiology

In general, ICD is more frequent than allergic contact dermatitis (ACD).

Definition

Non-allergic eczematous inflammatory reaction of the skin secondary to an external agent, not requiring sensitization.

Aetiology & Pathogenesis

ICD is caused by chemicals, which damage skin structures in a direct non-allergic way. Consequence of exposure to irritants. Dose-dependent. The most frequent chemical irritative factors are long lasting and repetitive contact with water (“wet work”), detergents, solvents or a combination of these factors.

Skin barrier perturbation leads to ICD. Once an irritant has penetrated the stratum corneum, the innate immune system is activated, and ICD reaction is initiated.

Signs & Symptoms

The morphology of cutaneous irritation varies widely and depends on the type and intensity of the irritant(s).

Localisation

ICD can involve any area of the body surface in contact with the irritant. The most common location for chronic ICD is the hands, often having occupational relevance.

Classification

Clinical classification of ICD is based on both morphology and mode of onset. The various forms of ICD include: acute and delayed type of contact ICD, irritant reaction, chronic ICD, traumatic ICD, acneiform ICD, non-erythematous irritation, subjective or sensory irritation, friction dermatitis and asteatotic (due to excessively dry skin) irritant eczema.

Laboratory & other workups

Patch testing is mandatory when ICD lasts longer than 3 months. Patch test results differentiate an allergic reaction from an irritative reaction.

Dermatopathology

Irritants produce a diversity of histopathological changes (epidermal necrosis, spongiotic dermatitis) depending on the concentration of the irritant, type, duration of exposure, site and individual reactivity of the skin.

Course

The course can be acute or chronic depending on the concentration and length of exposure to the exogenous substance.

Complications

ICD increases the risk of allergic contact sensitization. Superinfection of irritated skin by bacteria can occur (impetiginization).

Diagnosis

The diagnosis is based on the history, clinical features and localisation usually limited to areas of contact. It is necessary to rule out allergic contact sensitization using patch test.

Differential diagnosis

Allergic contact dermatitis. Psoriasis, Erysipelas.

Prevention & Therapy

The most important therapeutic approach is the identification of the causative chemical/s and climatic and mechanical factors. Mild forms may be controlled by the regular use of emollients. Severe relapsing forms require topical or oral corticosteroids, topical calcineurin inhibitors, ultraviolet light treatment and information on behavioral risks for prevention.

Special

Primary (health promotion by information), secondary (early detection of symptoms) and tertiary prevention (rehabilitation and prevention of recurrences are necessary. When ICD is related to professional activities, change of working place may be mandatory.

1.1.2.3 Irritant Contact Dermatitis