Dermatology Flashcards
Important aspects of a social Hx in dermatology
Occupation
Hobbies
Sun beds
Skin type
Macule =
change in skin colour without elevation
Papule =
circumscribed raised lesion (0.5-1mm)
Plaque =
a circumscribed, palpable lesion more than 1 cm in diameter; most plaques are elevated.
Nodule =
circumscribed raised lesion >1cm
vesicle =
raised lesion that contains fluid
bullae =
vesicle >0.5cm
lichen simplex =
hard thickening of skin with accentuated skin markings
nummular lesion =
coin like lesion
pustle =
lesions containing purulent material
ulceration =
loss of the whole thickness of the epidermis and upper dermis
heels with scaring
erosion =
superficial loss of epidermis, generally heels without scarring.
annular lesions =
lesions in a ring
reticulate =
net like
hidden areas in a full skin exam -
nails, web spaces, scalp, mouth and flexures.
Extra parts to a skin exam to offer -
Lymph nodes
Pulses
Joint examination
3 layers of skin
Epidermis
Dermis
Subcut layer
mild topical steroid -
1% hydrocortisone
moderate topical steroid -
2.5% hydrocortisone
Strong topical steroid -
betnovate
treat puritis in eczema with -
antihistamine
2nd line topical therapy for eczema -
topical tacrolimus
bandages
stockinette garments
3rd line for eczema -
phototherapy
systemic agents
common causes of secondary infection in eczema -
strep pyogenes and staph aureus
example of a combined antibiotic and steroid cream for secondary infection of eczema
fucidin H
secondary viral infection due to chicken pox in children with eczema -
molluscum contagiosum
dermatological emergency caused by HSV
eczema herpeticum
presentation of eczema herpeticum
areas of painful worsening eczema clustered blisters - like early cold sores punched out erosions fever lethargy distress
chronic plaque psoriasis
commonest clinical presentation of psoriasis
raised erythematous patches
covered with a silverly white build up of dead skin cells
often itchy / painful
Plaques are often found where in chronic plaque psoriasis?
Behind the ears Genitalia Scalp Nails Umbilicus Knees Elbows Natal Cleft
Guttate psoriasis =
small pink plaques on the trunk
raindrop lesions
often seen after a strep sore throat
1/3 go on to develop CPP
Flexural psoriasi =
psoriasi in genitalia / axillae - sites of friction
erythermatous and slightly shiny - don’t have the charactersitic scale
erythodermic psoriasis =
total body redness lack of clearly defined plaques skin is red, hot and painful can feel systemically unwell and become hypotensive should be admitted to hospital
generalised pustular psoriasis =
flare of psoriasis -> pustles with plaques
on which surfaces are psoriatic plaques usually found?
extensor
asupitz sign =
scratching of the plaques causes capillary bleeding
how many patients with psoriasis suffer from associated arthropathy ?
5%
Initial treatment for mild localised psoriasis
Emolliant regularly to improve scale
once a day topical potent steroid (not for longer than 8 weeks)
once a day vit D analogue
(applied one in morning and one at night)
What is used to treat extensive psoriasis?
phototherapy
oral therapies - methotrexate, retinoids, biologics (useful if joint disease)
Hormone conditions causing acne -
POCS Virilizing tumours Congenital adrenal hyperplasia Cushings Acromegaly
Medications causing acne -
Topical / systemic steroids OCP Phenytoin Barbituates Isoniazid Ciclosporin Lithium
Topical therapies for acne
Benzoyl peroxide
Azelaic acid
Topical AB
Topical retinoids
What should you not combine in terms of acne therapy?
Oral and topical AB
3 types of oral treatments for moderate - severe acne -
AB
Hormonal therapy - co-cyrindiol (anti androgen)
Oral retinoid (isoretinoin) - must be given be a dematologist
Size effects of isoretinoin
Severe skin dryness
Mucous membrane dryness
Nose bleeds
Joint pains
Other general principles of acne prevention
Avoid humid conditions
Stop smoking
Eat plenty of fruit and veg
Minimise application of oils and cosmetics
Abrasive skin treatments can aggrevate
Do not wash >2 p/d
Women should consider COC in those that require contraception.
Actinic keratoses =
Pre malignant skin condition
Found on exposed skin on those that have worked outdoors / exposed to high intensity UV
Rough areas of skin and can be raised keratotic lesions with irregular edges. Usually <1cm in diameter.
A skin that an actinic keratoses lesion may have malignant changes -
rapid growth / painful / inflamed
Management for actinic keratoses single lesions -
cryotherapy
Topical treatments for actinic keratoses -
5-Fluorouracil
Imiquimod
Topical NSAIDs
Risk factors for SCC
excessive UV exposure actinic keratoses chronic inflammation immunosuppression genetic predisposition
Presentation of SCC
Indular nodular lesions Often keratotic Ill defined May ulcerate Can be painful
Common sites for SCC
Face
Scalp
Back of hands
What clinical features suggested a poorer progression for SCC
tumour >2cm in size
Lesion on lip / ear
Hx of immunosuppression
Main management of SCC
Surgical excision (4-6mm margin) Radiotherapy - large non resectable lesions
Risk factors for BCC
Increasing age Fair skin High intensity UV exposure Radiation Immunosuppression Previous hx
Presentation of BCC
Small papules
Pearly and translucent quality
Clear to deeply pigmented
Treatment options for BCC
excision Radiotherapy Grafting Cuvettage Cautery Cryotherapy
ABCDE of malignant pigmented lesions
Asymmetry
Border (? irregular)
Colour - variation may be a sign of dysplasia / malignant change
Diameter (>1cm more likely to be malignant)
Evolving
What regulates melanocytes?
MSH
Junctional naevus =
melanocyte poliferation at the dermo-epidermal junction
brown and flat lesions
Intradermal naevus =
melanocytes in the dermis
skin coloured and raised
intermediate naevus =
central part melanocytes in the dermis
peripheral in the junction
so a raised centre with a brown border
compound naeuvus =
melanocytes at the junction and within the dermis
so raised brown lesion
risk factors for malignant melanoma
solar radiation light skin tones poorly tanning skin red / fair hair personal / FHx presence of giant congenital melanocyte naeve Multiple common moles Changes in moles
Prognosis in malignant melanoma depends on?
Breslow thickness
What indicates a poorer prognosis is multiple melanoma
Ulceration
Lymph node involvement
Skin mets
Treatment for MM
Exision with a 2mm marking
FNA if lymph node palpable
Treatment for uncomplicated cellulitis
Flucloxacillin
Treatment for MRSA cellulitis
Doxycycline - mild
Vancomycin - extensive
Which patients are at higher risk of cellulitis
Venous stasis
Lymphoedea
Diabetes
Who are at high risk of necrotising fascitis
IV drug user
Presentation of nec fas
pain out of proportion to the lesion
systemically unwell
rapid progression
post surgery / trauma
How to diagnosis NF
USS but also clinical diagnosis
Treatment of NF
Surgical debridement of all necrotic tissue
Wide spectrum of AB
Usual cause of gas gangrene
C perfirnges
Features of gas gangrene
Tender
Oedematous skin
Haemorrhaig blebs and bullae
Crepitus and palpation
What can gas gangrene progress to?
Toxaemia and shock
Treatment of gas gangrene
Debridement and excision
Amputation may be needed
Antibiotics
Erythroderma -
exfoliative dermatis involving at least 90% of the skin surface
Causes of erythroderma
Previous skin disease e.g. eczema and psoriasis
Lymphoma
Drugs
Idiopathic
Presentation of erythroderma
Skin inflammed, oedematous and scaly
Systemically unwell
Lympadenopathy
Malaise
Treatment of erythroderma
Treat the underlying cause
Emolliants
Wet wraps
Topical steroids to reduce inflammation
Major features of a lesion that needs to be referred for two week wait (these get 2 points)
change in size
irregular shape
irregular colour
Minor features of a lesion that needs to be referred for two week wait (these get 1 point)
Largest diameter >7mm
Inflammation
Oozing
Change in sensation
Other cases than the 7 point scale where 2 ww is considered
- dermatoscopy suggestes malginant melanoma
- SCC suspicion
BCC referral
routine referral
When is 2ww considered in BCC
When delay may have a significant impact e.g. due to lesion site / size
Applying emolliant and corticosteroids
wait 30mins between
how long after flare up of eczema should you apply corticosteroids?
48hrs
how often to apply corticosteroids?
once a day
patch
a large area of colour change, with smooth surface
action of vit d analogues in psoriasis?
they reduce scale but not erythema
Dermatitis Herpetiformis is?
Chronic itchy clusters of blisters.
Linked to underlying gluten enteropathy (coeliac disease).
Scoring system used in melanoma
Breslow depth
Kaposi’s sarcoma associated with which virus?
HHV-8
human herpes virus 8
Kaposi sarcoma?
Tumour of vascular and lymphatic endothelium.
Purple cutaneous nodules.
Associated with immuno supression.
Classical form affects elderly males and is slow growing.
Immunosupression form is much more aggressive and tends to affect those with HIV related disease.
Dermatitis Herpetiformis is?
Chronic itchy clusters of blisters.
Linked to underlying gluten enteropathy (coeliac disease).
