A patient may present with mild or no prodromal symptoms. Itching and burning might be experienced by the patients at the site of the eruption (1).
Distribution of lesions:
- symmetrically distributed lesions
- common sites are the back of the hands, palms, forearms, feet, toes - genital and oral lesions may be seen in Stevens-Johnson syndrome
- there is often a proximal spread of the lesions along an affected limb (1)
- the scalp is characteristically avoided
appearance of lesions:
- the appearance of lesions is very variable - the lesions may have central pallor with peripheral erythema or central erythema with peripheral pallor. Frank bullae may be present and represent epidermal necrosis
- the lesions begins as numerous, sharply demarcated erythematous macules which then become papular.
- these papules gradually evolve into plaques
- there may be crusting or blistering at the central portion of the lesion
- the characteristic target or iris lesions are regular round shaped lesions with 3 concentric zones:
- a central dusky or darker red area
- a paler pink or edematous zone
- a peripheral red ring
- some target lesion may contain only 2 zones - the dusky or darker red center and a pink or lighter red border .
Target lesions may become noticeable several days after the disease onset. These target lesions together with lesions of various clinical morphology accounts for the name erythema "multiforme" (1).
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