Emergency Dermatology Flashcards
What can skin failure lead too / all conditions
2 bacterial infection Sepsis Dehydration Electrolyte imbalance Hypo / hyperthermia Renal impairment Peripheral vasodilatation Cardiac failure
What is pirnciple of management of dermatological emergencies
Full supportive care - ABC of resus Withdrawal of any precipitating agent Fluid balance Temp regulation Emollients Anticipate and treat infection Management of any complications Specific Rx
What is erytheroderma and what can cause
An exfoliative erythematous dermatitis affecting >90% of body
Psoriasis
Eczema
Drugs - penicillins, cephalosporin, AED, allopurinol
Cutaneous lymphoma
Hereditary disorders
Abrupt steroid withdrawal in erythrodermis psoriasis
How does it present and what are complications
Inflammed oedematous scaly skin Itchy Systemically unwell - LN / malaise Secondary infection Fluid loss and electrolyte imbalance Hypothermia High output cardiac failure Capillary leak syndrome = most severe
What happens in erythodermis psoriasis
Progress to exfoliative phase
Plaques over whole body
Mild systemic upset
How do you manage erythroderma
ITU / burns unit Remove offending drug / treat cause Fluid balance Nutrition Temp regulation Emollient and wet wraps to maintain skin moisture Topical steroid may help relieve inflammation Oral and eye care Manage itch
What is urticaria
Weals / Hive’s
Acute <6 weeks
Chronic
What is pathophysiology behind / type of hypersensitivity
Type 1 - IgE if acute
Chronic less likely
Due to local increase in permeability of capillaries
Histamine from mast cell = major inflammatory mediator
How does it present
Central swelling - variable size that involves superficial dermis raising the epidermis
Surrounded by patchy erythematous rash
Associated dermal oedema / flushing of skin
Itching / burning as histamine released - ask if rash itchy
Usually lasts 1-24 Horus
What is associated with urticaria and where do they affect
Angiooedema
- Deeper swelling involving dermis and SC tissue
- Skin or muscle membranes so throat, tongue and lips
Anaphylaxis
- Bronchospasm
- Facial and laryngeal oedema
- Hypotension
- Can initially present with urticaria and angioedema
What causes acute urticaria
Idiopathic in 50% Allergy stimulating release of mast cell contents = most common Food Insect bites Chemicals - latex Viral or parasitic infection Drugs - ask if any new drug etc (NSAID, ACEI, opiates, thiazide, phenytoin) Autoimmune Vacinations Hereditary angioedema in some cases
How do you treat acute urticaria and associations if occur
Consider trigger and withdraw - opiate / NSAID
Oral anti-histamine 3x daily = mainstay
Corticosteroid if severe urticaria or angioedema + PPI
Treat as anaphylaxis if obstruction
What are complications
Urticaria = no complications
Asphyxia, cardiac arrest and death if angiodema / anaphylaxis
What causes chronic urticaria
Autoimmune disease where Ab target mast cells
Physical trauma
Vasculitis
How do you Rx
Anti-histamine
May need higher dose or 2nd
Consider Immunomodulant / biologic
Limited use of steroids
What should you consider if angiodema present
Anti-leukotriene
Tranexamic acid
Types of anti-histamine
Chlorophenamine = sedating
May have anti-muscarinic properties
Certrizine = non-sedating
When do drug reactions commonly begin
1-2 weeks after drug
What is mild drug reaction
Morbilliform exanthema
Macular red lesions
2-10mm but join up
Erythema multiform
What are severe drug reactions
Erythroderma
SJS - <10%
TEN >30%
DRESS
What are common drugs that cause / infection
Drugs = main cause Antibiotics - penicillin Anti-convulsants - phenytoin / carbamazepine Sulphonamides Allopurinol NSAID
Infection HSV Mycoplasma CMV HIV
What is SJS
Severe variant of erythema multiforme (<1 mucosal)
Mucocutaneous necrosis with 2+ mucosal sites involved
Skin involvement may be limited or extensive
How does it present
May have prodromal febrile illness Maculopapular rash <10% of skin surface Target lesions Blisters Mouth / genital / eye ulceration Cause greyish white membrane Fever Malaise Arhtralgia Histopathology = epidermal necrosis
How does TEN usually present
Prodromal febrile illness
Extensive skin and mucous membrane invovlement
Ulceration mucous membrane
May start macular or purpuric
Then blister
Become confluent >30% BSA
Leads to large loss of epidermis - desquamation
Systemically UNWELL
Nikolsky +ve - blisters form when rub back and forth
Histopathology = full thickness necrosis with detachment
Prognosis of TENS and SJS
Very serious
High mortality from sepsis / electrolyte imabalcen and multi-organ failure
How do you manage TEN / SJS
Early recognition and help ITU Stop culprit drug Full supportive care Nutrition Anti-septic Analgesia Opthamology input IV IG = 1st line Role of biologics / immunosuppression / steroid
What score to measure mortality
SCORTEN
What does it look at
Age Malignancy HR Initial epidermal detachment >10% Urea >10 Glucose >14 Bicarb <20
What are complications
Secondary bacterial infection Sepsis Multi-organ failure Electrolyte imbalance Pigmentary skin change Scarring Eye disease - blindness Nail and hair loss Joint contractures
What is DRESS
Drug reaction with eosinophilia and systemic symptoms
What happens
2-8 weeks after drug Fever Widespread rash Eosinophilia Deranged liver function Lymphadenopathy
How do you Rx
Stop drug
Systemic steroid
Immunosuppression / Ig
What is pemphigus vulgaris
Autoimmune disease where Ab at desmosomes within epidermis cause dermis and epidermis to stick together and causing epidermal intra-epidermal split
Desmoglein 3
Tends to affect middle age
What does it lead too
Flaccid blisters Rupture easily Form erosion and crust Typically painful Common at face, axillae and groin Mucosal ulceration common which can proceed skin NOT itchy Nikolsky's sign Patient very unwell If mucosal involvement = vulgaris Worse involvement
How do you Dx
Biopsy shows acanthylsis
How do you Rx
Wound dressing Monitor for infection Good oral care High dose oral steroid Immunosuppression - Methotrexate - Azathioprine - Cyclophosphamide - MMF
What is bullous pemphigoid
More common condition presenting in the elderly
Autoimmune where Ab directed at derma-epidermal junction causing sub-peridermal split and blister
What can it be a sign of
Underlying malignancy
What are the features
Intact epidermis forms roof of blister Itchy before blister Blister = tense and intact Erythematous base Do not break Can be haemorrhagic Trunk and upper limb Heal without scarring Patient well NO mucosal involvement
How do you Dx
Bloods
Biopsy
CXR for malignancy
How do you Rx
Wound dressing where required
Topical steroid if local
Oral steroid
Combination steroid / Ax / immunosuppression
Immunosuppression - not great if underlying cancer
What is erythema multiforme
Acute self-limiting hypersensitivity reaction triggered by
- HSV = most common
- Mycoplasma pneumonia
- Drugs
- SLE / sarcoid
- Malignancy
What drugs
Penicillin
OCP
NSAID
What happens
Abrupt onset of 100s of lesions over 24-72 hours Initially back of hands and feet Then torso Mucosal surfaces absent or LIMITED TO ONE surface Widespread itchy erythematous rash Target lesion Symmetrical with central blister Pink macule becomes elevated May blister Occasional pruritus Severe form = SJS / TEN May have associated fever, arthralgia, stomatitis
How do you Rx
Self limiting A form of SJS so early recognition important Resolve over 2-6 weeks Treat underlying cause If underlying cause not known - CXR to look for pneumonia If severe may need admission for IV fluid, analgesia and steroid Steroid for itch remains controversial
What is eczema herpeticum
Disseminatd HSV infection on background of atopic eczema or less commonly other skin conditions
What are the features and what are complications
Widespread eruption Extensive crusted papule Monomorphic blisters + vesicles Punched out erosion Painful NOT itchy but can be Systemically unwell - fever, lethargy
Secondary infection
Herpes hepatitis
Encephalitis
DIC
How do you Rx
Acyclovir - oral or IV
Mild steroid for eczema
Ophthalmology review if near eyes
Ax if bacterial secondary infection
What should you consider if happens in a adults
Underlying immunosuppression e.g. HIV
What causes generalised pustular psoriasis
Infection
Sudden withdrawal of steroids
Can occur without psoriasis
What are features
Rapid development of generalised erythema + pustules
Fever
Elevated WCC
How do you Rx
Avoid steroid in psoriasis patient
Systemic therapy
Treat infection
What is staph scaled skin syndrome and who is it common in
S.Aureus produces toxin which targets desmoglein 1 and causes skin to break down
Children
Immunocompromised adults
What are features
Hx of staph infection initial Develops within hours - days Worse over face, neck, groin Diffuse erythematous rash VERY PAINFUL Scald like skin appearance followed by large flaccid bullae Blisters / bullae form Intra-epidermal blistering Nikolsky +ve - rubbing skin causes it to peal Desqaumation Systemically unwell - Fever / Irritability Recovery within 5-7 days
How do you Rx
Admit IV Ax Analgesia Fluid balance as prone to dehydration Usually make a full recovery without scarring
What is necrotising fasciitis
Rapidly spreading infection of deep fascia with secondary tissue necrosis
Infection may not be noticeable on skin initially as affecting deep structures
What causes
Group A strep
What are RF
Abdo surgery
DM
Malignancy
How does it present
SEVERE pain
Erythematous, blistering and necrotic skin
Swelling
Systemically unwell with fever and tachycardia+ hypo
After 3-4 days necrotic change occurs - rash swells and becomes dark purple with blisters
Presence of crepitus
What does crepitus suggest
Subcutaneous emphysema as gas in the tissue
What may X-ray show
Presence of gas (absence does not exclude)
How do you manage
ABCDE Bloods VBG - lactate + metabolic acidosis Urgent referral for surgical debridement IV Ax Transfer to ITU
What should you beware of
Pain out of proportion even if no skin involvement yet
What are the 3 types
Type 1 = poymicrobial - DM and elderly Type 2 = flesh eating (strep pyogenes) - Most common and can occur in healthy Type 3 = clostridium - Post op or IVDU
What is Fournier gangrene
NF affecting perineal area
High mortality
Wh is no pain a bad sign
Means that necrosis has destoyed peripheral nerves
Unlikely to improve with Ax
What are complications
Amputtion
Death
What are DDX
Cellulitis - minimal systemic toxicity
Cutaneous anthrax - IVDU / animal contact and tends to be painless pruritic papule that go on to necrose
