Derm Flashcards
What is the bacteria that plays a role in acne?
Propionibacterium acnes
What is acne vulgaris?
A common inflammatory skin disease which occurs in adolescents.
Characterised by obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules
How would you start to treat mild acne?
Single topical therapy:
Topical retinoids // Benzoyl peroxide
What is the step wise progression to treat acne?
1) T - Topical retinoids // Benzoyl peroxide
2) TT - Topical retinoids // Benzoyl peroxide // topical abx (erythromycin)
3) PO abx erythromycin//doxy
4) PO isotretinoin (only under specialist supervision)
Define eczema
Chronic, pruritic inflammatory skin condition
Defect in skin barrier function + immune dysregulation post allergen exposure
What are the streatment steps in eczema?
1) basic treatment - emollients, avoid triggers and irritants
2) mild - low potency TCS
3) Mod - + topical calcineurin inhibitors
4) Garmets/wet wipes/paste bandages
5) V severe - systemic CS // phototherapy
What is psoriasis?
A chronic inflammatory skin condition due to hyperproliferation of keratinocytes
What are the types of psoriasis?
Chronic plaque Guttate Pustular Erythrodermic Flexural Seborrhoeic
How do you treat chronic plaque psoriasis?
C: educate, avoid precipitants, emollients
T: VD analogues, TCS, coal tar preparaitons
Phototherapy UVB
M: Methotrexate // po retinoid (acitretin) // ciclospotin
Biologics TNFa blockers infliximab
Give an example of a VD analogue and how does it help in psoriasis?
Calcipotriol
Decreases cell proliferation
How do you treat seborrhoeic dermatitis if it is on the scalp?
Topical shampoos = ketoconazole
TCS
How do you treat seborrhoeic dermatitis if it is not on the scalp?
TCS + ketaconazole
May have a yeast infection which is driving the inflam
Give primary prevention steps for preventing skin cancers
Sun cream
Avoiding sunlight
Avoid tanning
Covering areas
Give the other names for:
1) Pre-malignant SSC
2) In-situ SSC
1) Pre-malignant SSC = actinic change
2) In-situ SSC = Bowen’s disease
Bullous pemphigoid is a blistering skin disease which mainly affects the elderly.
What is it caused by?
Autoabs against antigens between the epidermis and dermis causing a subdermal split in the skin
How is bullous pemphigoid treated?
C - wound dressings and monitoring for infection
T - TCS // TCI
M - Pred, combo of doxy + nicotinamide, immunosuppressive agents
Give 2 of the main bacterial causes of cellulitis
Staph aureus
Strep pyogenes
What abx would you give for cellulitis?
PO flucloxacillin
What abx would you give for a septic patient with cellulitis who is severely ill?
IV Tazocin
What is the cause of scalded skin syndrome?
Due to the production of a circulating epidermolytic toxin from benzylpenicillin-resistant (coag positive) staph
SSSS = staph scalded skin syndrome
How is SSSS treated?
IV Abx - flucloxacillin
Analgesics
IV fluids
They usually have to be admitted
Urticaria - itchy wheals wih swelling of the superficial dermis causing the epidermis to be raised.
How is it treated?
Anti-histamines
+ systemic corticosteroids
Give some causes of erythema nodosum
IBD
TB
Throat infection - post strep
Sarcoidosis
What is erythema multiforme?
It is a hypersensitivity reaction triggered by HSV
Describe the characteristic lesion seen in erythema multiforme
Target lesions
Sharp margin, regular round shape with 3 concentric colours
Give a similarity and a difference difference between Stephen Johnson syndrome and Toxic Epidermal Necrosis
They both have mucocutaneous necrosis with at least 2 mucosal sights, +ve Nikolsky sign
SJS - <10% total body area
10% mortality
TEN - >30% total body area 30% mortality
What can be the cause of death in patients with Stepheb-Johnson syndrome or toxic epidermal necrosis?
Dehydration Shock and multi-organ failure Sepsis VTE/DIC ARDS
What are some of the LT complications that occur with SJS and TEN?
SCARRING --> loss of nails, scarred genitalia Joint contractures Lung disease Eye problems can lead to blindness
What is erythroderma?
It is exfoliative dermatitis involving >90% of the skin surface
The skin is inflamed oedematous and scaly
They are systemically unwell with lymphadenopathy and malaise
What are the complications of erythroderma?
Hypothermia (temperature dysregulation)
Fluid loss –> electrolyte imbalance and dehydration
High output HF
Capillary leak syndrome
Secondary skin infection can lead to impetigo and cellulitis
How is erythroderma managed?
It is a serious and potentially life threatening condition.
Admit
Restore fluid and electrolytes
C: Maintain skin moisture with wet wraps and dressings
T: TCS
Treat underlying cause - PO CT// methotrexate
What is necrotising fasciitis?
it is a rapidly spreading bacterial infection of the deep fascia with secondary soft tissue necrosis
The bacteria multiple and release toxins and enzymes which cause thrombus in the vessels –> necrosis
What are the organisms which cause necrotising fasciitis?
GROUP A STREP Staph aureus Haemophilus E.coli Clostridium
How would someone with necrotising fasciitis present?
Severe pain - disproportional to what you see
Flu-like symptoms
Area swelling with purpleish rash which becomes blacker when the necrosis occurs. Oedema. Crepitus in the skin due to gas in the tissues.
Severe pain until the necrosis destroyed the peripheral nerves and then they pain subsides
How do you manage necrotising fasciitis?
Admit
Swabs/culture guided IV Abs
Start broad and then tailor depending on results (Vanc + taz)
–> urgent surgical debridement to remove all the necrotic tissue
Up to 25% of patients with necrotising fasciitis die. What could be the causes of death?
Renal failure
Septicaemia
Muti-organ failure
