Psoriasis Flashcards
What is psoriasis?
Chronic inflammatory skin disease characterised by well demarcated inflamed scaly plaques.
What is the epidemiology of psoriasis?
Equally common in men and women with bimodal onset: two peaks between 10-20 yrs old and 50-60 yrs old.
What are the pathophysiological factors of psoriasis?
Multifactorial due to genetic and environmental predispositions.
What are the genetic factors associated with psoriasis?
Patient commonly has a family history of psoriasis.
What infectious factors can cause psoriasis?
Mostly caused by streptococcal infections; can also be caused by HIV.
What social factors contribute to psoriasis?
Stress, alcohol, and smoking.
What drug factors can trigger psoriasis?
Changing/new medication, drug classes such as beta-blockers, lithium, antimalarials, and tapering steroids.
What immune system factors are involved in psoriasis?
Inflammatory cytokines and T-lymphocytes.
What is Koebner’s phenomenon?
A phenomenon where psoriasis lesions appear at the site of trauma.
What are the different types of psoriasis?
Chronic plaque psoriasis, scalp psoriasis, nail psoriasis, guttate psoriasis, flexural/inverse psoriasis, palmoplantar pustulosis, and generalised pustular psoriasis.
Describe chronic plaque psoriasis.
Well-demarcated, pink/erythematous plaques with scaling, typically distributed over extensor surfaces and trunk.
What are the characteristics of scalp psoriasis?
Well-demarcated scaly plaques extending beyond the hairline and onto the neck, associated with transient hair loss.
What are the differentials for scalp psoriasis?
Tinea capitis, contact dermatitis, seborrheic dermatitis.
What changes does nail psoriasis cause?
Chronic changes such as pitting, onycholysis, and subungual hyperkeratosis.
What are the differentials for nail psoriasis?
Fungal nail infections such as onychomycosis, eczema, lichen planus.
Describe guttate psoriasis.
Widespread, small erythematous raindrop-shaped plaques, most common in children or following streptococcal infection.
What is the typical course of guttate psoriasis?
Usually acute and resolves spontaneously after phototherapy, but can progress to chronic plaque psoriasis.
What characterizes flexural/inverse psoriasis?
Shiny, smooth plaques with few scales, localized to skin folds and intertriginous areas.
What are the differentials for flexural/inverse psoriasis?
Seborrheic dermatitis, cutaneous candidiasis, tinea incognito, contact dermatitis.
What is palmoplantar pustulosis?
Sterile yellow/brown/erythematous pustules widespread over palms and soles, associated with skin peeling and crusting.
What is generalised pustular psoriasis?
Life-threatening form characterised by widespread sheets of sterile pustules on erythematous skin.
What are the associated symptoms of generalised pustular psoriasis?
Associated with pyrexia and haemodynamic instability.
What complications can arise from generalised pustular psoriasis?
Secondary bacterial infection, electrolyte disturbance, renal and liver impairment.
