Which skin condition is described by iris-like target lesions?

Iris-like target lesions are characteristic of erythema multiforme, a condition often associated with a variety of triggers such as infections (especially herpes simplex virus), medications, and other factors. The target lesions typically present as concentric rings of color, resembling a 'bull's-eye,' with the central area being dark red or purplish and surrounded by lighter and more erythematous skin.

The appearance of these lesions is due to a hypersensitivity reaction, often involving the skin and mucous membranes, that leads to the characteristic morphology. Erythema multiforme can range in severity, with mild cases being self-limited and more severe forms, such as Stevens-Johnson syndrome, requiring more intensive treatment and management.

Other conditions like erythema nodosum present with painful nodules rather than target lesions, psoriasis typically shows silvery scales on well-defined plaques, and contact dermatitis is usually characterized by redness and vesicles due to an allergic reaction, without the distinct target morphology seen in erythema multiforme.