Final answer:
Erythrodermic psoriasis is the form that involves the entire skin surface, which is severe and can be life-threatening. It causes widespread symptoms like severe itching, pain, and scaling. It generally requires systemic treatment and careful management.
Step-by-step explanation:
The form of psoriasis that involves the entire skin surface is known as erythrodermic psoriasis. This extreme form of psoriasis can lead to widespread inflammation and exfoliation of the skin over the majority, if not entire, body surface. In erythrodermic psoriasis, patients may experience severe itching, pain, and scaling. It may occur in association with severe sunburn, use of systemic steroids or other medications, or another form of psoriasis that becomes unstable. The treatment of erythrodermic psoriasis is complex and often requires systemic therapy and the management of potential complications, such as fluid loss, infection, and thermoregulation issues.
Psoriasis itself is a chronic skin disorder where cell turnover is accelerated, leading to an accumulation of skin cells on the surface forming thick, inflamed patches. While erythrodermic psoriasis is a rare and severe form of psoriasis, other common forms include plaque psoriasis, which manifests as thickened, red patches with silvery scales most often on the elbows, knees, and scalp. Psoriasis is not just a skin condition; it can have systemic effects and is associated with psoriatic arthritis.