Aetiology is multifactorial. Contact irritants are the commonest external causes. Hand eczema caused by such irritants, or mild toxic agents, is called irritant contact dermatitis. Causal factors that are less common than irritants are contact allergens. Hand eczema caused by skin contact with allergens is called allergic contact dermatitis. Ingested allergens (for example nickel) may also provoke hand eczema. Water is a contact irritant and thereby an external causal or contributing factor. Being atopic (a tendency to develop asthma, hay fever or eczema) is the major predisposing factor responsible for hand eczema. There are several types of hand eczema of which the cause or predisposing factor is unknown. These (partly overlapping)
types are not precisely defined and are commonly described as: hyperkeratotic, tylotic, endogenous, dyshidrotic, pompholyx and nummular. In particular, dyshidrotic eczema is the subject of debate: a hallmark is recurrent vesiculation, which may or may not be associated with factors such as nickel allergy, atopy and other factors. In many patients a combination of the aforementioned factors seems to play a role. The relevance of psychosomatic factors remains speculative.
Was this article helpful?