Psoriasis is characterized by the appearance of papules of varying sizes, erythematous plaques covered with silvery-white scales and clearly defined borders, which are more common on the scalp, extensor surfaces of the extremities and back. It is more common in men than in women. The clinical manifestations and pathological characteristics of psoriasis are generally divided into six types: 1. Erythrodermic psoriasis: it is a more serious and rare type, this type refers to the diffuse red, dark red infiltrative lesions on about 70% of the skin of the whole body, with a large number of furfur-like flakes on the surface, sometimes in the armpits, the root of the thighs and umbilicus due to swelling and epidermal peeling and exudation, the oropharynx, nose and conjunctiva can be congested and red, patients Patients often have fever and chills, headache and general discomfort. 2.Pustular pustulosis: including pustular psoriasis of the palm and pustular bacterial rash. 3.Common psoriasis: the rash generally occurs on the scalp, trunk and extremities, red papules appear on the skin, gradually expanding and fusing into patches or plaques, with thick silvery white phosphorous flakes on the surface, irregular shape, some have a map or island-like appearance, some lesions are smaller, more, with a starry appearance, the scales fall off layer by layer, gently scraping off the flakes can see a thin layer of red membrane, scraping off the red membrane can See small bleeding dots, some people called blood dew, medical also called sieve bleeding, this is the clinical characteristics of common psoriasis. 4. Arthritic psoriasis: It is rare and can occur at any age. It can occur in both large and small joints, but it is common in the small joints of the wrists, fingers and toes, and it can also occur in the spinal joints. The diseased joints have redness, swelling, pain, severe joint cavity with fluid, swelling of the skin near the joints with restricted activity, and joint stiffness over time, and in severe cases the joints are seen to be destroyed on X-ray, with fast blood sedimentation, often with fever and other systemic symptoms, but the rheumatoid agglutination factor is negative, arthritic psoriasis, skin damage is mostly accompanied by thick oyster shell-like lesions, or there may be only the erythematous and silvery skin of common psoriasis damage. 5, continuous acrodermatitis: characterized by sterile pustules, so some people also consider it to be the same disease as pustular psoriasis. Some people think it is a subtype of pustular psoriasis, but there are also different opinions that it should be an independent disease. It occurs in middle-aged people and is mostly caused by post-traumatic injury. 6. Pustular psoriasis: divided into generalized and limited. The pustular psoriasis is mostly of acute onset, and can be pustular within a few days to a few weeks to spread throughout the body, first with dense pinpoint-sized potential small pustules, soon fused into a pus lake, often accompanied by high fever, joint swelling and pain and general discomfort, blood tests can see an increase in white blood cells, pustules dry up, followed by desquamation, and after the desquamation, there are new pustules appear. Restricted pustular psoriasis is more common in palm and toe pustular psoriasis. There are symmetrical erythematous spots on the palms of both hands and toes, and pinhead-sized to chestnut-sized to small pustules appear on the erythematous spots: they dry up on their own after about 1-2 weeks, and new pustules appear after desquamation, and the disease stretches repeatedly and persistently.