Emergency Dermatology

Question 1

What are four true skin emergencies that require urgent dematological input?

Answer 1

Erythroderma
Toxic Epidermal Necrolysis
Angioedema
Acute Blistering disorders

Question 2

What is erythroderma? What diseases can cause it?

Answer 2

Widespread redness of the skin
Involvement of over 90% of the skin of an inflammatory or neoplastic disease. Examples include:
Psoriasis
Eczema
Drugs
Cutaneous T Cell Lymphoma

Question 3

Why can erythroderma become life-threatening?

Answer 3

There is systemic upset leading to vasodilation, decreased blood pressure and tachycardia. Large amounts of heat are also lost.
This results in high output cardiac failure.

Question 4

What are the signs of erythroderma?

Answer 4

Skin is warm to touch
Widespread redness affecting 90% or more of BSA
Itching
Eyelid swelling may result due to scratching
If due to psoriasis may have associated nail changes

Question 5

What are some complications of erythroderma?

Answer 5

Heat loss
Fluid loss
Electrolyte abnormalities
High-output heart failure
Risk of developing secondary skin infections such as impetigo and cellulitis

Question 6

How is erythroderma diagnosed?

Answer 6

History and Examination
(Note nail changes associated with psoriasis, weeping associated with eczema)
Skin Biopsy if uncertain of cause and can investigate for cutaneous T-Cell Lymphoma

Bloods- Raised WCC, Eosinophilia (could indicate T-Cell Lymphoma), ESR, CRP, U&Es, Creatinine (Risk of AKI), LFTs

Question 7

What is the treatment for erythroderma?

Answer 7

Admit
Discontinue unnecessary medications
Fluids and monitor fluid status
Wet wraps and emollients to maintain skin moisture
Antibiotics if any bacterial infection
Antihistamines- could reduce itch and sedation

Treat the cause- e.g. Oral steroids, methotrexate, ciclosporin, azathioprine, acitretin

Question 8

What are some drugs that can cause erythroderma?

Answer 8

Sulfonamides
Allopurinol
Carbamazepine
Gold

Question 9

What can cause acute blistering?

Answer 9

Staph scalded skin syndrome
Toxic epidermal necrolysis
Immunobullous disease
Insect Bites
Eczema- e.g. Palmar-plantar pustular eczema

Question 10

What is staphylococcal scalded skin syndrome?

Answer 10

Due to toxins produced by staphylococcus bacteria which cause red blistering that looks like a scald or burn

Question 11

What are the toxins that are released in staphylococcal scalded skin syndrome called? What do they target?

Answer 11

Epidermolytic toxins A and B

They target the desmosomes- specifically desmoglein 1

Question 12

Who is at risk of staphylococcal scalded skin syndrome?

Answer 12

Infants and young children

Anti-bodies develop during childhood that prevent this happening in adults

Question 13

Neonates with what other comorbidity are at greater risk of staphylococcal scalded skin syndrome

Answer 13

Kidney disease- as the toxins are cleared through the kidneys and so reduced clearance increases levels of the toxins

Question 14

What are the signs and symptoms of staphylococcal scalded skin syndrome?

Answer 14

Blistering- fluid filled blisters burst
Intense redness
Raised temperature/ fever
Irritability
Raised WCC, CRP, ESR
Nikolsky sign- gentle strokes of the skin cause exfoliation

Question 15

What might be done to diagnose staphylococcal scalded skin syndrome?

Answer 15

History and examination
Urgent dermatology assessment 
Skin Biopsy
Bacterial Cultures- from skin, blood (at risk of sepsis), urine and umbilical cord sample in new-born baby
Tzanck Smear

Question 16

What is the Tzanck smear used for?

Answer 16

To distinguish Steven-Johnsons Syndrome/TEN from Staphylococcal scalded skin syndrome.

Helps to differentiate the cause of a number of blistering skin conditions

Question 17

What is the treatment for staphylococcal scalded skin syndrome?

Answer 17

Hospitalisation
IV Antibiotics- e.g. Flucloxacillin, Clindamycin, Vancomycin if MRSA
Paracetamol to reduce pain and fever
Intense monitoring for fluid balance

Question 18

What is Steven-Johnsons Syndrome/ TEN? What is the difference between the two?

Answer 18

Immune mediated condition that cause blistering of the skin and mucosal membranes.

Toxic epidermal necrolysis is the more severe form.

Question 19

What is the process resulting in Steven-Johnsons syndrome/TEN? What type of hypersensitivity reaction is seen?

Answer 19

Drug reaction where the drug metabolites causes cells to be recognised as foreign and so an immune response is generated against them. Skin and mucosa are affected.

It is a type IV hypersensitivity reaction- Cytotoxic T Cell Mediated

Question 20

What is the difference between TEN and Steven-Johnson Syndrome?

Answer 20

Steven-Johnson’s- Less than 10% of the body affected
TEN- More than 30% of BSA affected

(Overlap at 10-30%)

Question 21

What are some drugs that cause TEN/Steven- Johnsons Syndrome?

Answer 21

Anti-epileptics such as Carbamazepine, Lamotrigine, Phenytoin
Antibiotics such as Sulphonamides (cotrimoxazole), Penicillin
Immune Modulators such as Sulfasalazine
NSAIDs such as Aspirin, Oxicam
Paracetamol

Question 22

What surfaces does TEN/Steven-Johnsons Syndrome affect?

Answer 22

Skin and mucosal linings

Question 23

What are the symptoms of TEN/Steven-Johnsons Syndrome?

Answer 23

Early on Flu-like Sx:
Fever >39
Sore throat and painful swallowing
Cough and runny nose
Sore red eyes
General aches and pains

Rash Development:
Tender, painful red skin rash
Often starts on trunk and extends rapidly over hours to days onto the face and limbs
Macules, diffuse erythema, blisters
Target lesions
Mucosal ulceration
Progresses to sloughing off of dead skin/mucosal surfaces. Nikolsky Positive (exfoliation on gentle touching of skin)

Question 24

If suspecting TEN/Steven-Johnsons Syndrome what should you ask about in the history?

Answer 24

Have you started any new medications recently?

Question 25

What features does mucosal involvement cause in TEN/Steven-Johnsons Syndrome?

Answer 25

Conjunctivitis- red, sore, sticky Oral ulceration Red/Crusting lifts Painful swallowing (pharyngitis/oesophagitis) Cough due to upper respiratory tract involvement Diarrhoea- due to GI involvement

Question 26

What are some complications of TEN/Steven-Johnsons Syndrome?

Answer 26

``` Dehydration Infections of the damaged surfaces Septicaemia ARDS Hypoperfusion and shock DIC ```

Question 27

How is TEN/Steven-Johnsons Syndrome diagnosed?

Answer 27

History and examination Skin biopsy- can do Tzanck Smear, Microscopy (exclude other causes of blistering), immunofluorescence (indicates immunobullous disorders) Bloods- Show low WCC, low Neutrophils. Raised CRP/ESR

Question 28

What scoring system is used to estimate the risk of mortality in TEN/Steven-Johnsons Syndrome?

Answer 28

SCORTEN is a scoring system used to predict mortality

Question 29

What is the treatment for TEN/Steven-Johnsons Syndrome?

Answer 29

Stop the causative drug Admit and urgent dermatology referral Supportive Treatment- ICU, HDU Fluids- risk of dehydration and high output cardiac failure Analgesia as very painful Sterile handling and isolate to reduce risk of secondary infections Protect the skin inc topical antiseptics, dressings, emollients Temperature care- keep warm as can lose a lot of heat IV Ig/ Plasmapheresis/ Cyclosporine /Cyclophosphamide / Anti-TNF If eye involvement involve ophthalmology Note- Steroids are not used as they increase the risk of infection. Psychological support is important too. Include dermatology nurses for advice on dressings. IVIg is the most widely used and has been found to be effective

Question 30

If a patient has been successfully treated for TEN/Steven-Johnsons Syndrome what is it important to do?

Answer 30

Advice not to take the drug again | Educate of similar drug classes and not to avoid these incase of cross reaction

Question 31

What are some features that would make you consider an insect bite as a cause of blistering?

Answer 31

Localised Grouped together Seasonal Puncture site

Question 32

What is angioedema?

Answer 32

An acute swelling of the skin and mucous membranes. All parts of the body can be affected but it most commonly occurs around the eyes and lips

Question 33

Why is angioedema life threatening?

Answer 33

If it involves the URT it can cause airway obstruction = death

Question 34

What is the difference between angioedema and urticaria? Group answer by Area affected, Appearance, Associated Features

Answer 34

Urticaria is more common and less severe than angioedema. Area Affected- Urticaria only affects the skin (epidermis and dermis) whereas angioedema affects the subcutaneous and sub-mucosal surfaces. Appearance- Urticaria appears as red, itchy patches Angioedema causes soft tissue swelling so leads to swelling around the lips and eyes. Associated features- Urticaria is often itchy Angioedema is often accompanied by pain and tenderness, itch is much less common.

Question 35

What are some causes of angioedema?

Answer 35

Allergy (Angioedema within 1-2 hours of exposure)- Food allergy, drugs (e.g. penicillin, NSAIDs, Vaccines) insect bites, bee stings. Non-Allergic Drug Reactions- ACEi can cause this, onset days or months after stating medication Idiopathic Hereditary- Rare autosomal dominant disease Acquired C1 Inhibitor deficiencies can occur with B cell lymphoma or antibodies generated against C1 inhibitor

Question 36

What are the features of angioedema?

Answer 36

``` Swelling around the lips and eyes Associated pain and tenderness Known causative agent if allergic May or may not be itchy GI cramps and pains if swelling there Difficulty breathing, tight chested ```

Question 37

What does allergic angioedema usually occur with?

Answer 37

Urticaria- so there is often associated itching and redness of the skin.

Question 38

What drug has been known to cause a non-allergic angioedema?

Answer 38

ACE inhibitors- this occurs without accompanying urticaria

Question 39

Does hereditary angioedema occur with urticaria?

Answer 39

It does not

Question 40

What is the treatment for acute angioedema?

Answer 40

Medical emergency as there is a risk of airway compromise so ABCDE approach- secure the airway. Could his be anaphylaxis- treat according to anaphylaxis protocols Adrenaline, Steroids, Anti-histamines

Question 41

What are the doses of adrenaline, hydrocortisone and chlorphenamine if anaphylaxis/angioedema in a child less than 6 months old?

Answer 41

Adrenaline IM- 150 micrograms (0.15ml 1 in 1,000) Hydrocortisone IV- 25mg Chlorphenamine IM/IV- 250 micrograms/kg Adrenaline can be repeated every 5 minutes if necessary. Inject at anterolateral aspect of middle third of thigh.

Question 42

What are the doses of adrenaline, hydrocortisone and chlorphenamine if anaphylaxis/angioedema is a child aged 6 months to 6 years?

Answer 42

Adrenaline IM 150 micrograms (0.15ml 1 in 1000) Hydrocortisone IV- 50mg Chlorphenamine IM/IV- 2.5mg Adrenaline can be repeated every 5 minutes if necessary. Inject at anterolateral aspect of middle third of thigh.

Question 43

What are the doses of adrenaline, hydrocortisone and chlorphenamine if anaphylaxis/angioedema in a child aged 6-12?

Answer 43

Adrenaline IM 300 micrograms (0.3 1 in 1000) Hydrocortisone IV- 100mg Chlorphenamine IM/IV- 5mg Adrenaline can be repeated every 5 minutes if necessary. Inject at anterolateral aspect of middle third of thigh.

Question 44

What are the doses of adrenaline, hydrocortisone and chlorphenamine if anaphylaxis is expected in a child aged 12 or older or an adult?

Answer 44

Adrenaline IM- 500 micrograms (0.5 1 in 1000) Hydrocortisone IV- 200mg Chlorphenamine IM/IV- 10mg Adrenaline can be repeated every 5 minutes if necessary. Inject at anterolateral aspect of middle third of thigh.

Question 45

What investigation can be done to see if a patient had true anaphylaxis?

Answer 45

Serum tryptase- remains elevated for upto 12 hours afterwards

Question 46

What causes hereditary angioedema?

Answer 46

C1 inhibitor deficiency

Question 47

What is the management for angioedema is anaphylaxis has been ruled out?

Answer 47

Protect the airway Regular antihistamines e.g. Chlorphenamine, Certrizine Steroids e.g. Prednisolone If drug induced (ACEi) use an alternative

Question 48

What are the features of urticaria?

Answer 48

Weals- transient oedematous dermal papules and plaques. Individual lesions persist for less than 24 hours Itching Red, pink or white weals Raised

Question 49

What is the cause of acute urticaria?

Answer 49

Most often the cause is unknown Often allergy and type I (IgE mediated) hypersensitivity E.g. Drugs, Foods, Latex, Bee sting, Plants Infection- URTI, Bacterial infections, Viral hepatitis, infectious mononucleosis (glandular fever), mycoplasma

Question 50

What is physical urticaria?

Answer 50

``` This accounts for 50% of urticaria cases and can be due to: Light touch Pressure Heat Sweat cold Water Sunlight Direct contact with irritants ``` (It's triggered by physical causes)

Question 51

What is the most common form of urticaria?

Answer 51

Spontaneous urticaria No cause is usually identified and often patients have urticaria co-exist with angioedema

Question 52

What causes urticaria?

Answer 52

Mast cell degranulation which releases histamine. Histamine is vasodilator leading to redness and oedema, it also causes itching.

Question 53

What test might be done to identify the cause urticaria in cases thought to be due to allergy?

Answer 53

Skin prick testing as it is a type I hypersensitivity reaction Note- allergic contact dermatitis is type IV and patch testing is done for this

Question 54

What monoclonal antibody is helpful in patients with type I hypersensitivity reactions?

Answer 54

Omalizumab- it is an anti IgE antibody May be used for the treatment of chronic urticaria

Question 55

What is the treatment for urticaria?

Answer 55

Antihistamines- cetirizine, loratadine Avoid known trigger factors Cool affected areas with cold compresses, ice packs, cooling creams NOTE- IF SUSPECTING ANAPHYLAXIS MANAGEMENT IS WITH ADRENALINE, HYDROCORTISONE AND ANTIHISTAMINE. REPEAT ADRENALINE EVERY 5 MINUTES IF NEEDED.

Question 56

What should you think about if someone has a rash like uriciaria but there is no wheeling?

Answer 56

Scombroid fish poisoning- due to scombrotoxin being produced in fish that has not been stored properly. Can occur with mackerel and tuna. Features include- racing heart, nausea and vomiting, abdominal pain, difficulty breathing, collapse due to low blood pressure.

Question 57

What is eczema herpeticum?

Answer 57

This is an disseminated infection of the skin by HSV It is characterised by fever, multiple blisters and punched out erosions. Blisters produce a clear fluid which can be sent for PCR.

Question 58

Which patients are more prone to developing eczema herpeticum?

Answer 58

Patients with atopic dermatitis/eczema. This is because there are breaks in the skin which reduce the barrier immunity. It is most commonly seen in infants and small children

Question 59

What are the features of eczema herpeticum?

Answer 59

Blistering lesions Multiple and appear similar to each other May be filled with a clear yellow fluid or thick purulent material Punched out appearance of blisters Weeping and bleeding of blisters Lesions heal over 2-6 weeks and this can be with or without scaring

Question 60

How is eczema herpeticum diagnosed?

Answer 60

History and Examination Escalate to a dermatologist as can be severe If there is any eye involvement or Hutchinson's Sign involve and opthamologist Swabs from the lesions- PCR and MC + S due to secondary bacterial infections which can occur. Vital culture and Tzanck smear

Question 61

What is the treatment for eczema herpeticum?

Answer 61

Admit for anti-viral therapy Oral Aciclovir 400-800mg 5 times daily Or Valaciclovir 1 g BD Both for 10 -14 days and longer if lesions haven't healed. IV Aciclovir if PO not suitable or deteriorating patient.