Though the normal course of psoriasis is chronic, there occurs occasionally an acute attack in the form of guttate psoriasis.
In this variety, small discrete papules develop rapidly all over the body, particularly the trunk, the arms and the thighs.
Acute guttate psoriasis is usually, precipitated either by an acute illness like tonsillitis or a sharp mental stress or physical injury. It is more common in children than adults.
When a rapid spreading and Joining together of individual lesions takes place in psoriasis, it becomes generalized and may produce an erythroderma-like picture viz., generalized erythema and scaling of the whole of the integument.
Some typical individual lesions can always be detected in this variety; the history also helps to differentiate it from the other causes of erythroderma.