Psoriasis Flashcards
What is psoriasis?
Chronic, immune mediated disease
What are the 2 classes of psoriasis?
Type 1- runs in families and is early onset
Type 2- related to autoimmune conditions and environmental triggers and an older population
What causes psoriasis?
Polygenic predisposition and environmental truggers
What are the environmental triggers of psoriasis?
Infection
Drugs
Trauma
Sunlight
What is the appearance of psoriasis?
Sharply demarcated erythematous plaque with micaceous scale
What part pf the immune system os psoriasis associated with?
Adaptive immune system
What is the pathogenesis of psoriasis?
Stressed keratinocytes cause activation of dermal dendritic cells (dDC) via interleukins and TNFa
dDC= travel to lymph nodes and activate naive T cells to T helper cells that target skin and cause psoriatic dermic and plaque formation
IL and TNFa= amplify inflammatory cascade and stimulate keratinocyte proliferation
High serum VEGF caused angiogenesis
Cell cycle is reduced from 28 to 3-5 days
What is the histology of psoriasis?
Hyperkeratosis Neutrophils in stratum corneum Psoriasform hyperplasia Dilated dermal capillaries T cel infiltration
What i hyperkeratosis seen as histologically?
Thickening of stratum corneum
What is psoriasform hyperplasia seen as histologic;ly?
Thickening of squamous cell layer
What history should be taken for psoriasis?
Age and nature of onset Distrubution Effective treatments Medical history Family history Medications Quality of life
What are the signs and symptoms of psoriasis?
Sharply demarcated, erythematous plaques Numerous small, widely disseminated papule ad plaques Erythroderma Nail pitting and oil spots, onycholysis Koebner phenomenon Woronoff's ring
What is Koebner phenomenon?
Lesions along area of injury
What is Woronoff’s ring?
Blanched halo around lesions after phototherapy
What are the types of psoriasis?
Chronic plaque psoriasis Guttate psoriasis Palmo-plantar psoriasis Scalp psoriasis Nail psoriasis Plexural/inverse psoriasis Pustular psoriasis Erythrodermic psoriasis
What is the appearance oc chronic plaque psoriasis?
Large salmon coloured plaques with thick scale
Symetric, extensor surfaces
What is the trigger of guttate psoriasis?
Viral or bacterial infection
Who is guttate psoriasis seen in?
Children and adolescents
Wha is the appearance of guttate psoriasis?
Multiple pink papule with fine scale
What are the possible outcomes of guttate psoriasis?
REsolve
Trigger chronic psoriasis
What is palm-plantar psoriasis associated with?
SMoking
What is the appearance of palmo-plantar psoriasis?
Thick, scaly and red with yellow/brown lesions at the edges
What is the appearance of scalp psoriasis?
Alopecia at affected areas
Pink hyperkeratotic plaques
Severe dandruff
What is the appearance of nail psoriasis?
Pitting or oil spots on nails
What is the issue with nail psoriasis?
Difficult to treat
What is the appearance of flexural psoriasis?
Skin pink or red sharply demarcated plaques
Less scaly
What triggers flexural psoriasis?
Localised dermaphyte, candida or bacterial infection
What is th appearance of pustular psoriasis?
Sterile pustules and generalised red tender patches
Sometimes systemic symptoms
What are the triggers of pustular psoriasis?
Pregnancy
Rapid tapering or stopping steroids
Hypoglycaemia
Infection
What is the appearance of erythrodermic psoriasis?
Red man syndrome
>80% body surface involved- erythematous with fine scale
Hypotensive and pyrexial
What is the differential diagnosis for psoriasis?
Seborrhoeic dermatitis
Lichen planus
Mycosis fungoides
What is the treatment of psoriasis in primary care?
Emollients Soap substitutes Vit D analogues Coal tar creams Topica steroid Salicylic acid
What is the treatment of psoriasis in dermatology?
Crude coal tar
Dithranol
UVB phototherapy
What is the systemic treatment of psoriasis?
Retinoid
Immunosuppression
Biologics
What immunosuppressants are used in psoriasis?
Methotrexate
Ciclosporin
What is the treatment of erythrodermic psoriasis?
Admit FLuid balance Bloods Thick greasy ointment/emollient Systemic treatment
