psoriasis牛皮癣银屑病.pptx

Definition
Psoriasis is a common, chronic, recurrent, inflammatory disease of the skin characterized by red papules（丘疹） and plaques（斑块） covered with scaling（鳞屑）.
Introduction
牛皮癣
Incidence: -3%
M:F ratio: 1:1
Age of onset: 25 - 33 yrs
Season： spring
winter
( Epidemiology. Chapter IV, A Psoriasis. Jacobson CC, Kimball AB )
Etiology
1．Hereditary factors
20% +ve family history
Early-onset type (16-22 yrs) has a stronger hereditary association than the late-onset type (57-60 yrs).
HLA-Cw6, DR7 antigen with psoriasis
Genes responsible：1q、3q、4q、6p、17q
polygenic inheritance
2. Triggering factors
Infection: bacteria (streptoccoci A), virus, yeast 　
Environment: trauma, surgery, pregnancy,
alcohol consumption, smoking
Psychological: emotional stress, death event, family problem 　
Drugs: β- blockers, angiotensin-converting enzyme inhibitors(ACEI), antimalarials, lithium
Etiology
Theory
After processing by antigen presentation cell, the antigen is presented to CD4 T-lymphocytes → production of cytokines → stimulate keratinocytes → proliferation and expression of adhesion molecules by endothelial cells → infiltration of leukocytes into the skin lesions
Immunopathogenesis
Types of Psoriasis
Psoriasis vulgaris (寻常型银屑病)
Pustular psoriasis (脓疱型银屑病)
Arthropathic psoriasis (关节型银屑病)　
Erythrodermic psoriasis (红皮病型银屑病)
Psoriasis Vulgaris (寻常型银屑病)
Typical lesions(皮疹）: circumscribed red papules and plaques covered with thick silvery or white scales
Severe Psoriasis
Lesion features: dropping wax candle (蜡滴现象)
thin membrane (薄膜现象)
　　　　　 Auspitz’s sign (点状出血)
Sites：extensor surface of the extremities
(elbows, knees), scalp, lumbosacral area,
genital region.
Symptom: itching 20%
Psoriasis Vulgaris (寻常型银屑病)