EMERGENCY DERMATOLOGY

Question 1

What is urticaria?

Answer 1

Local or generalised superficial swelling of the skin
Usually caused by allergy but non-allergy causes can be seen

Question 2

Features of urticaria?

Answer 2

Pale pink, raised skin
Pruritus

Question 3

Management of urticaria?

Answer 3

Non-sedating antihistamines

Prednisolone can be used for severe or resistant episodes

Question 4

Drug causes of urticaria?

Answer 4

aspirin
penicillins
NSAIDs
opiates

Question 5

What is angioedema?

Answer 5

Rapid swelling underneath the skin in the deep dermis and subcutaneous tissues
Usually caused by an allergy or retraction to a medication

Question 6

What causes urticaria?

Answer 6

Inflamationlocal increase in permeability of capillaries and small venues
Histamine derived from skin mast cells are the major mediator

Question 7

Where does angioedema typically affect?

Answer 7

The lips and tongue

Question 8

What is erythema nodosum?

Answer 8

Inflammation of subcutaneous fat which causes tender, erythematous, nodular lesions
Usually occurs over shins but can occur elsewhere

Question 9

Causes of erythema nodosum?

Answer 9

Infections - strep, TB, brucellosis
Systemic disease - sarcoidosis, IBD, Behçet’s
Malignancy/lymphoma
Drugs - penicillins, sulphonamides, COCP
Pregnancy

Question 10

What is erythema multiforme?

Answer 10

A hypersensitivity reaction most commonly triggered by infections

Question 11

Features of erythema multiforme?

Answer 11

Target lesions initially on back of hands/feet and then torso
Pruritus can occur

Question 12

Causes of erythema multiforme?

Answer 12

Viruses - HSV, off
Idiopathic
Bacteria - mycoplasma, strep
Drugs - penicillins, sulphonamides, COCP, NSAIDs, allopurinol, carbamazepine, nevirapine
Connective tissue disease e.g. SLE
Sarcoidosis
Malignancy

Question 13

What is erythema multiforme major?

Answer 13

A more severe version with 1 or more mucous membranes involved

Question 14

Prognosis of erythema nodosum?

Answer 14

lesions continue to appear for 1-2 weeks and leave bruise-like discolouration as they resolve
They dont ulcerate and resolve without atrophy or scarring

Question 15

What is stevens-Johnson syndrome?

Answer 15

A rare but serious skin reaction
Also known as toxic epidermal necrolysis

Cause systemic illness, circular rash, blisters and sores on lips/mouth/throat/eyes/urethra

Question 16

Appearance of meningitis rash?

Answer 16

Rash usually starts as small red purpura before spreading quickly and turning into red/purple blotches
Non-blanching

Question 17

What is erythroderma?

Answer 17

When >95% of the skin is involved in a rash of any kind

Question 18

Causes of erythroderma?

Answer 18

Eczema
Psoriasis
Drugs e.g. gold
Lymphomas and leukaemias
Idiopathic

Question 19

What is erythrodermic psoriasis?

Answer 19

Progression of chronic psoriasis to an exfoliating phase with plaques covering most of the body
Associated with mild systemic upset

Question 20

Management of erythema multiforme and stevens-Johnson syndrome?

Answer 20

Early recognition and call for help
Full supportive care to maintain haemodynamic equilibrium

Question 21

Complications of erythroderma?

Answer 21

Secondary infection
Fluid loss and electrolyte imbalance
Hypothermia
High-output cardiac failure
Capillary leak syndrome
Mortality 20-40%

Question 22

Management of erythroderma?

Answer 22

Treat underlying cause where known
A->E
Assess fluid balance
Emolients and wet-wraps
Start on antibiotics if any signs of infection
Refer to derm

Question 23

What is eczema herpeticum?

Answer 23

Severe primary infection of thr skin by herpes simplex virus 1 or 2
More commonly seen in children with atopic eczema

Question 24

Features of eczema herpeticum?

Answer 24

Rapidly progressing painful rash
Monomorphic punched-out erosions 1-3mm in diameter
Systemically unwell with fever and malaise

Question 25

Management of eczema herpeticum?

Answer 25

Admit children for IV aciclovir

Question 26

What is necrotising fasciitis?

Answer 26

Medical emergency
A rapidly spreading infection of the deep fascia with secondary tissue necrosis

Question 27

Causes of necrotising fasciitis?

Answer 27

Mixed anaerobes and aerobes (type 1)
Strep pyogenes aka group A strep (type 2)

Question 28

Presentation of necrotising fasciitis?

Answer 28

Acute onset pain, swelling and erythema. Often presents with rapidly worsening cellulitis with pain out of keeping with physical features
Extremely tender over infected tissues with hypoaesthesia to light touch
Skin necrosis and gas gangrene are late signs
Systemically unwell - fever, tachycardia

Question 29

What can be seen on XR in necrotising fasciitis?

Answer 29

Soft tissue gas

Question 30

Average mortality rate for necrotising fasciitis?

Answer 30

20%

Question 31

Management of necrotising fasciitis?

Answer 31

Urgent surgical referral debridement
IV antibiotics

Question 32

Most commonly affected site for necrotising fasciitis?

Answer 32

Perineum
Known as fournier’s gangrene