Wk2- DERM Flashcards
Define psoriasis
chronic inflammatory skin disease of well demarcated, erythematous plaques with detachable silver scales.
What is the cause of psoriasis
Genetic- dysregulation of immune system (associated with metabolic syndrome)
Pathophysiology of psoriasis
hyperproliferation skin by reduced keratinocyte turnover time
Complications of psoriasis
- Psoriatic arthritis (incidence in 15-25% with psoriasis)
- Erythroderma psoriasis - redness over the body
- Koebner phenomenon - lesions on healthy skin after trauma
Define eczema/dermatitis
non infective inflammatory skin disorders that are extremely itchy
Classifications of eczema/dermatitis
Exogenous - something outside body is causing it (allergy, irritant)
Endogenous - “ inside (atopic, asteatotic)
Acute- sudden, aggressive
Chronic- long duration, mild irritation
What is asteatotic exzema
-itchy dry skin with loss of lipids involving the dermis layer
-often occurs in winter and with the elderly (80)
What is nummular eczema
Coin shaped symmetrical lesion
-cause unknown
What is atopic eczema
-family history, environmental factors + genetics play a role.
-Itch that turns into a rash.
-Infants/children- face, neck, extensors
-Any age- flexural lesions (not groin or axillary areas
What is irritant contact dermatitis (ICD)
inflammatory reaction to a noxious substance on the skin (most common)
What is allergy contact dermatitis (ACD)
inflammatory reaction that is immmune mediated after multiple exposures to a substance
Signs of contact dermatitis (6)
- Erythema
- Saying
- Blistering
- Weeping
- Fissuring
- Intense itching
What is juvenile plantar dermatosis
-no contact allergy
-resolves at puberty
-treated with cork insoles
What is pompholyx associated with
Hyperhidrosis and nickel allergy
How can bacterial skin infections cause death
- Infection
- Infection of lymph vessel
- “ lymph node
- Bacteria in blood
- Blood poisoning
- Death
Classifications of bacterial skin infections
- Impetigo- superficial infection: subcorneal layer of epidermis (mainly staph), contagious. Blisters which rupture and crust.
- Ecthyma- infection of epidermis
- Erysipelas- acute infection of upper half of dermis (strep). Oedema, redness, tender. Recurrence is typical.
- Cellulitis- infection of lower half of dermis. More extensive infection than the above
- Necrotising fasciitis- infection of subcutaneous fat and deep fascia.
What is tinea pedis and its pathophysiology
-itchy, dry scaling, maceration of feet (different symptoms for different spores)
-digest keratin in epidermis as a food source for survival
Onychomycosis: what is it, how does it occur and what are the different classifications
-fungal nail
-occurs typically as a secondary infection from tinea pedis, trauma to nail allows for penetrate
- Distal subungal onychomycosis (DSO)- typically first stage
- Total dystrophic onychomycosuis (TDO)- next stage
- White superficial onychomycosis (WSO)- specific form of OM
How to diagnose fungal infection
- Diafactory test
- Microscopy and culture
What is verruca pedis, what are the signs, pathophysiology
-plantar wart
-interruption of skin lines, pinpoint bleeding, pain on lateral compression
-HPV encourages basal cell replication and hyperplasia of layers
