What is Contact dermatitis

Contact dermatitis is an eczematous skin reaction caused by direct and usually repeated exposure to harmful objects or chemicals.

Dependent on the point of contact, it can occur anywhere on the body including mucous membranes. It is typically characterised by itching papules or vesicles but may vary from slight hyperkeratosis (thickening of the outermost horny layer) and small fissures to extensive redness, swelling and oozing.

A histopathological examination of a biopsy shows an acute inflammation in the outermost layers of the dermis with involvement of the epidermis. Only superficial parts of the skin are thus involved, and healing is complete with no residual scars.

The main pathogenetic mechanisms are damage to the skin barrier and/or immunological reactions.

Types of contact dermatitis

There are four different forms of contact dermatitis: