Dermatology Flashcards
What skin condition can steroids lead to
Acne
What skin condition can immunosuppression lead to
Skin cancer
What is tinea corporis
Ringworm - a fungal skin infection
What does tinea corporis look like
An oval ring of scaly red patches that form a ring around an area of central sparing
Which number T helper cell is involved in a) Eczema b) Psoriasis
Eczema - Th2
Psoriasis - Th1
What structure can you use when describing skin lesions
Distribution Type of lesion Shape Edge Colour Secondary features
Ways you can describe the distribution of skin lesion/rash
Central/distal Symmetrical/asymmetrical Flexor, extensor, truncal, palmar, plantar Localised/generalised Dermatomal Follicular Photosensitive/exposed
Ways you can describe the type of skin lesion
Macule Papule Vesicle Pustule Patch Plaque Nodule Bullae Erosion
What is a macule defined as
A flat lesion <0.5cm
What is the size limit for papules, vesicles, pustules
<0.5cm
What is a patch defined as
A flat lesion >0.5cm
What is a plaque defined as
A flat lesion >1cm and palpable
What would you call a raised lesion >0.5cm
Nodule
What would you call a raised lesion >0.5cm and filled with fluid
Bullae
Ways you can describe the shape of a skin lesion
Circular Linear Annular (ring, target) Irregular Reticulated (like a net) Discoid
Ways you can describe the edge of a skin lesion
Well demarcated
Ill defined
Raised/flat
Confluent
Ways you can describe the colour of a skin lesion
Erythematous
Pigmented/hypopigmented
Purpuric/violaceous
Black/brown/tan
Some of the secondary features that may be associated with a skin lesion/rash
Crust Scale Keratosis Lichenification Erosion Excoriation Fissure Ulceration Desquamation (peeling) Exudate Verrucous/warty Dry
What are the two main types of exogenous eczema
Irritant/allergic contact
Photosensitive/photoallergic
What are the 7 types of endogenous eczema
Atopic Seborrhoeic Asteatotic Discoid Pityriasis alba Pompholyx Varicose
Classic description of the rash of atopic eczema
Papules and vesicles with an erythematous base over the flexor surfaces
Classic description of the rash associated with seborrhoeic dermatitis/eczema
Greasy/scaly erythematous rash around the nose/ears/scalp
Classic description of asteatotic eczema/dermatitis
Cracked dry skin on lower limbs
Classic description of pityriasis alba
Pink scaly patches that later leave hypopigmented areas of skin
Classic description of pompholyx eczema/dermatitis
Itchy blisters/vesicles on lateral aspects of fingers and toes. It’s an acute presentation of eczema
What is lichenification
Increased skin markings - seen in chronic eczema
Classic description of wheals
Transient, circumscribed, elevated papules or plaques with erythematous borders and pale centres
Features of infected eczema
Weeping Pustules Crust Not improving with normal treatment Rapidly worsening Fever Malaise
Complications of untreated eczema herpeticum
Hepatitis
Encephalitis
Pneumonitis
Features of eczema herpeticum
Rapidly worsening painful areas of clustered blisters. Punched out uniform erosions (circular, depressed, ulcerated), may become confluent areas of erosion with crusting
Systemic fever, lethargy, distress
Which virus causes eczema herpeticum
Herpes simplex 1
A combined steroid + antibiotic cream used for localised skin infections
Fucidin
What class of topical treatments reduce T cell response
Topical calcineurin inhibitors e.g. Tacrolimus
Underlying pathological process that causes psoriasis
Epithelial turnover is accelerated - 3-4 days rather than weeks. Also inflammatory and autoimmune aspects.
What are the differences between type 1 and type 2 psoriasis
Type 1;
75%
Presents <40 years old
HLA-CW6 gene associated
Type 2;
25%
Presents age 55-60
No gene association
A child who has one parent with psoriasis has what chance of having it themselves
1 in 4
Which type of psoriasis often happens after a strep throat infection
Guttate psorasis
What is erythrodermic psoriasis
A psoriasis flare than covers 90% of the body surface, become hypotensive and need admission
What is generalised pustular psoriasis
A flare of psoriasis with red/hot/painful pustules that develop within plaques. Usually as a result of steroid withdrawal. Needs emergency admission.
How does alcohol affect psoriasis
Makes it worse/less responsive to treatment
Medications that can trigger psoriasis
Antimalarials NSAIDs Non-selective beta blockers Lithium Terbinafine (oral anti-fungal)
Nail changes associated with psoriasis
Pitting
Onycholysis
Periungal erythema
Subungal hyperkeratosis
What is Auspitz’s sign
The appearance of punctate bleeding spots when psoriasis scales are scraped off
Criteria for referral of psoriasis to dermatology
Erythroderma >20% body area involved (extensive) Severe disabling psorasis Failure to respond to topical treatments Unstable/rapidly extending psoriasis
What score/tool is used as an objective measure of psoriasis severity
PASI - Psoriasis area severity index
What score/questionnaire is used to subjectively measure the severity of skin diseases
DLQI - Dermatology life quality index
What score is used to screen for psoriatic arthritis
PEST score
How do light therapies work for psoriasis
Slow keratinocyte growth
Underlying patho of acne vulgaris
Blockage and inflammation of the pilosebaceous unit
Keratinisation and plugging of the follicle leads to build up of sebum from the sebaceous gland which causes inflammation
Which bacteria plays a role in acne
Propionbacterium acnes
Which hormones plays a role in acne
Androgens
What do you call the non-inflammatory lesions seen in acne
Comedones - open (black heads) or closed (white heads)
What do you call the inflammatory lesions seen in acne
Papules
Pustules
Nodules
What scale is used to assess the psychosocial effects of acne
APSEA scale
What scoring system is used to assess the clinical severity of acne
Leeds scoring system
Indications for oral retinoids (Isotretinoin) in acne
Moderate and not responding to treatment or relapsing Severe acne Scarring Unusual form of it Psychological impact
Topical retinoids are particularly good at treating which aspect of acne?
Comedones
In general, how long to acne treatments take to work
8 weeks - 3 months. So follow up usually 8-12 weeks after each treatment initiation
What is acne fulminans/acne maligna
A a rare skin disorder presenting as an acute, painful, ulcerating, and hemorrhagic clinical form of acne. It may or may not be associated with systemic symptoms such as fever and polyarthritis. Acne fulminans also may cause bone lesions and laboratory abnormalities.
What is acne conglobata
A highly inflammatory disease presenting with comedones, nodules, abscesses, and draining sinus tracts.
Is basal cell or squamous cell carcinoma more common
BCC
Risk factors for BCC and SCC
Chronic UV exposure
Fitzpatrick skin type 1 + 2
Immunosuppression
Previous SCC
Which syndrome is strongly associated with developing basal cell carcinomas
Gorlin syndrome (naevoid basal cell carcinoma syndrome)
Risk factors for SCC specifically
Smoking
Chronic ulcers
Xeroderma pigmentosum
What is the name of the system used to describe skin types
Fitzpatrick
Describe Fitzpatrick skin type I
Always burns, never tans
Pale white skin
Ginger/blonde hair
Blue/hazel eyes
Describe Fitzpatrick skin type II
Usually burns, tans poorly
Fair skin
Blue eyes
Describe Fitzpatrick skin type III
Burn turns into tan
Darker white skin
Describe Fitzpatrick skin type IV
Tans easily, burns minimally
Light brown skin
Describe Fitzpatrick skin type V
Tans dark brown, rarely burns
Brown skin
Describe Fitzpatrick skin type VI
Always tans dark, never burns
Dark brown/black skin
Typical description of SCC
Fast growing, hardened nodular lesion with crusted/hyperkeratotic surface. May ulcerate and may be painful
Typical description of BCC
Slow growing, pearly translucent nodule with telangiectasia
What is Bowen’s disease
Squamous cell carcinoma in situ
High risk features of primary SCC that would need MDT discussion
Location - ear, lip, eyelid, nose, scale
Size - >20mm wide, >4mm deep, invading below dermis
Immunosuppression
Recurrent
Advice regarding sun protection for patients with skin cancer history
UVA+UVB protection, SPF 30+, star rating 3/4 (UVA protection), apply 30 mins before then every 2hrs, don’t rub it in just apply a film, wear a hat and appropriate clothing, stay in shade 11am-3pm
Treatment options for BCC
Leaving them (if elderly) Imiquimod cream Photodynamic therapy Radiotherapy Surgical excision
Describe a junctional naevus
Brown + Flat
Melanocytes are are the dermo-epidermal junction
Technical name for a mole
Melanocytic naevus
Describe an intradermal naevus
Skin coloured + Raised
Melanocytes are in the dermis
Describe an intermediate naevus
Centre is raised and skin coloured but edge is flat and brown
Describe a compound naevus
Brown + Raised
Melanocytes in the dermo-epidermal junction and dermis
What are the 3 main types of skin cancer
BCC
SCC
Melanoma
Is assessing for skin cancer mets what do you examine for
Lymphadenopathy
Hepatosplenomegaly
What scale is used to stage/assess prognosis of melanomas
Breslow thickness scale
How long does pruritus need to be present for to class as chronic
> 6 weeks
What is pruritus
Itch without rash
What is prurigo
Intensely itchy papules and nodules
Non-dermatological causes of widespread itch
Post-herpetic neuropathy OCD, anxiety Hyperthyroidism DM CKD causing hyperparathyroidism and uraemia Cholestasis Hodgkins leukaemia Dermatomyositis Scleroderma Medication
