Dermatology & Plastics Flashcards
Skin Layers (8)
Epidermis: - stratum corneum - stratum lucidum (only on palms/soles) - stratum granulosum - stratum spinosum - stratum basale Dermis Subcutaneous layer
Urticaria
Aetiology (3)
Infections and parasites
Chemicals: insect bites, latex, drugs (penicillin, contrast)
Foods: nuts, sesame seeds, shellfish
Urticaria
Pathology (1)
Local increase in capillary and small venule permeability due to increase in large numbers of inflammatory mediators (mainly histamine) released from mast cells
Urticaria
Signs + symptoms (1)
Smooth erythematous itchy hives and wheals
Urticaria
Treatment (2)
Anti-histamines
Corticosteroids if severe
Angioedema
Aetiology (3)
Foods: nuts, sesame seeds, shellfish, dairy
Drugs: penicillin,contrast
Insect bites
Angioedema
Signs + symptoms (1)
Tongue and lip swelling
Angioedema
Treatment (1)
Corticosteroids
Erythema Nodosum
Aetiology (4)
Inflammatory bowel disease
Strep infection
Malignancy
Sarcoidosis
Erythema Nodosum
Pathology (1)
Hypersensitivity response causing inflammation of subcutaneous fat
Erythema Nodosum
Signs + symptoms (2)
Discrete tender nodules
Continue to appear for 1-2 weeks before leaving bruise-like discolouration before resolve
Erythema Multiforme
Aetiology (1)
Hypersensitivity reaction triggered most often by HSV (or drugs)
Erythema Multiforme
Signs + symptoms (4)
Target lesions, round and well defined
On extensor surfaces of peripheries (palms and soles)
Evolve at different stages (mutliform)
Mucosal involvement only if severe (major form)
Erythema Multiforme
Treatment (4)
Not required in most cases
Topical steroid may relieve discomfort
Treat cause eg. aciclovir for HSV
Usually resolves spontaneously without scarring within 4 weeks
Stevens-Johnson Syndrome
Aetiology (1)
Drugs: sulfonamides, anti-epileptics, penicillins, NSAIDs
Stevens-Johnson Syndrome
Signs + symptoms (3)
Vague upper respiratory tract symptoms 2-3 weeks after starting drug and approx. 2 days before rash
Rash involves <10% body surface: painful erythematous macules evolving into target lesions
Severe mucosal ulceration of >2 surfaces (eg. conjunctivae, mouth, labia, urethra)
Stevens-Johnson Syndrome
Treatment (4)
ICU/HDU/burns unit
IV fluids
IV immunoglobulins
Analgesia
Stevens-Johnson Syndrome
Prognosis (1)
> 30% mortality (leads to sepsis and multi-organ failure)
Toxic Epidermal Necrosis
Aetiology (5)
Sulfonamides Anti-epileptics Penicillins Cephalosporins Allopurinol
Toxic Epidermal Necrosis
Signs + symptoms (3)
Flu-like prodrome
Skin infection affects >30% of body surface: widespread painful dusky erythema, then necrosis of large sheets of epidermis
Mucosae severely affected
Toxic Epidermal Necrosis
Treatment (4)
ITU/HDU/burns unit
IV fluids
IV immunoglobulins
Analgesia
Toxic Epidermal Necrosis
Prognosis (1)
> 30% mortality
Erythroderma
Aetiology (4)
Previous skin disease (eczema, psoriasis)
Sulfonamides
Allopurinol
Carbamazepine
Erythroderma
Signs + symptoms (3)
Widespread erythema and dermatitis affecting >90% of body surface
Scaly, exfoliative skin
Systemically unwell with lymphadenopathy and malaise
