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Flashcards in Derm Deck (58):
1

malignant melanoma definition

invasive, malignant tumour of the epidermal melanocytes which has the potential to metastasize

2

malignant melanoma epidemiology

Least common skin cancer
Average age is 63 years (but can affect much younger people ~30 years)
Most life-threatening type of skin cancer and affects younger population

3

malignant melanoma risk factors

modifiable:
- excessive UV exposure

non-modifiable:
- Skin type I (always burns, never tans)
- History multiple moles, atypical moles
- Family history melanoma
- Previous history melanoma

4

malignant melanoma presentation

Presentation: ABCDE
Asymmetrical shape
Border irregularity
Colour irregularity
Diameter >6 mm
Evolution of lesion (size, shape)
Symptoms: itch, bleeding
Legs in women, trunk in men

5

malignant melanoma investigations

Investigation(s)
If seen in GP: refer to dermatology with 2 week wait
Examination with dermatoscope in secondary care
Definitive: full thickness excisional biopsy
Atypical melanocytic lesion - take photographs and r/v at 3 months
If there is a suggestion of metastases:
CXR (lung mets)
Liver ultrasound (liver mets)
CT chest, abdomen, pelvis
Brain MRI

6

melanocytic lesions

Seborrheic wart
Elderly
Often multiple
Wart-like, greasy
Stuck on appearance

Congenital naevi
Can be large, pigmented, hairy

Junctional naevi
Small, flat, dark

Compound naevi
Raised, warty, hairy

Intradermal naevi
Dome-shaped papule/nodule

7

BCC definition

slow growing locally invasive tumour of basal cells of the epidermis, rarely metastasizes

8

BCC epidemiology

older individuals, most common (skin) cancer

9

BCC risk factors

modifiable
- Excessive UV exposure
- Frequent/severe sunburn in childhood

non-modifiable
- Skin type I
- Older age
- Males
- Immunosuppression
- Previous history skin cancer
- Family history skin cancer

10

BCC presentation

most common over head and neck (nose)

nodular (most common)
- small
- skin coloured nodule
- surface telangiectasia
- pearly rolled edge
± Ulcerated centre (rodent ulcer)

superficial
- flat

sclerosing/morphea
- scar like

pigmented
- may appear like melanoma

11

BCC investigations

Routine referral to dermatology – NOT 2 week wait
Examine with a dermatoscope
The lesion is then usually removed

12

SCC definition

locally invasive malignant tumour of the epidermal keratinocytes or its appendages, with potential to metastasize

13

SCC aetiology

Excessive UV exposure
Pre-malignant skin conditions
e.g. actinic keratoses
Chronic inflammation e.g. leg ulcer,
wound scar (Marjolin’s ulcer)
Immunosuppression
Family history

14

SCC presentation

Keratotic (scaly, crusty)
Ill-defined nodule
May ulcerate
Non-healing lesion
Everted edges

15

SCC investigations

Refer to dermatology (2 week wait)
Dermatoscope
(Biopsy) & excision

16

A 64 year old man presents with a lesion on his upper ear that has been present for months but has now begun to ulcerate. On examination: non-pigmented, hyperkeratotic, crusty lesion with raised everted edges on the pinna.

What is the most likely diagnosis?
Non-healing scab
Basal call carcinoma
Squamous cell carcinoma
Malignant melanoma – superficial spreading type
Malignant melanoma – nodular type

Squamous cell carcinoma

17

A 32-year old scuba diver who lives in the Maldives had a seizure three days ago. He has no history of epilepsy but he’s had headaches for the past 5 months. The headaches are worse when he goes to bed. On examination, a dark irregular skin lesion is found on the back of his neck. An MRI scan shows multiple lesions across both cerebral hemispheres.

What is the most likely diagnosis?
Glioblastoma multiforme
Metastases
Neurofibromatosis type I
Acoustic neuroma
Meningioma

metastases

18

A 76-year-old woman has recently attended her GP because of a ‘spot that won’t go away’. The lesion is on her nose and has rolled edges. The GP suspects a basal cell carcinoma.

What investigations are likely to be needed?
Dermatology referral/assessment - 2-week wait
Dermatology referral/assessment – routine
None – it is a non-dangerous chronic condition
None – GP to start treatment
Re-assessment in primary care periodically

Dermatology referral/assessment – routine

19

molluscum contagiosum risk factors

Transmission: close contact, swimming pools, sexual contact
HIV infection
Atopic eczema

20

molluscum contagiosum presentation

Dome shaped, flesh coloured, pearly white papules
Central umbilication
May be >100 if immunocompromised/HIV
Systemically well
No investigations needed: clinical diagnosis

21

what is the differnece between cellulitis and erysipelas?

Cellulitis: acute bacterial infection of the dermis and subcutaneous tissue
Erysipelas: distinct form of superficial cellulitis which is sharply demarcated

22

cellulitis and erysipela aetiology

Streptococcus pyogenes
Staphyloccus aureus
(H. influenzae – periorbital)

23

cellulitis and erysipela risk factors

Immunosuppression
Wounds, ulcers
IV cannulation
Skin injury: cut, scratch, insect bite

24

cellulitis and erysipela presentation

Cellulitis & erysipelas: acute onset red, painful, hot, swollen skin
More common with erysipelas: systemically unwell fever, malaise, rigors
Erysipelas: well-defined raised border
Periorbital cellulitis:
Causes painful, swollen skin around eye
Orbital cellulitis:
Causes visual impairment/limited movement
Medical emergency

25

cellulitis and erysipela investigation

(Mainly clinical)
FBC: high WCC
Skin swabs not routinely recommended

26

cellulitis and erysipela management

Mild cases:
Draw around lesion
Elevate leg
Encourage oral fluids
Paracetamol/ibuprofen
Oral antibiotics: flucloxacillin
Manage underlying risk factors/comorbidities (e.g. DM)
Admit if:
Acute confusion, tachycardia, tachypnoea, hypotension (sepsis

27

cellulitis and erysipela complications

Complications:
Local necrosis
Abscess
Septicaemia
Necrotising fasciitis
Orbital cellulitis:
Visual impairment
May need orbital decompression surgery
Prognosis: good with treatment

28

necrotising fasciitis definition

rapidly spreading infection of the deep fascia with secondary tissue necrosis

29

necrotising fasciitis aetiology

group A haemolytic streptococcus, mixture aerobic/anaerobic bacteria

30

necrotising fasciitis risk factors

Surgical wounds
Skin breakage: IV drug use, trauma
Medical comorbidities e.g. diabetes, malignancy
50% occur in previously healthy people

31

necrotising fasciitis presentation

Severe pain
Erythematous blistering, necrotic skin (late sign)
Systemically unwell: fever and tachycardia
Crepitus (subcutaneous emphysema)

32

necrotising fasciitis investigations

FBC: high white cells
U+E: high urea due to volume depletion
High CRP, serum CK
Blood and tissue cultures
XR/CT: may show soft tissue gas
Urgent referral: extensive surgical debridement

33

A 7-year old girl presents with multiple lesions on her face. The lesions are raised and shiny, non-tender, non-erythematous, and 3 mm in diameter. They have an umbilicated centre. The patient is known to be HIV positive.
What is the most likely diagnosis?
Chicken pox
Molluscum contagiosum
Atopic eczema
Eczema herpeticum
Herpes simplex virus

Molluscum contagiosum

34

A 52-year-old woman presents to the GP with redness and swelling of her right cheek. On examination the area of erythema is well-demarcated and warm to the touch. Her temperature is 37.9oC and she feels unwell.

Most likely diagnosis?
Cellulitis
Skin abscess
Erysipelas
Necrotising fasciitis
Gum infection

Erysipelas

35

A 52-year-old woman presents to the GP with redness and swelling of her right cheek. On examination the area of erythema is well-demarcated and warm to the touch. Her temperature is 37.9oC and she feels unwell.

Next steps?
Cold compress, reassure, home
Admit to intensive care unit
Take skin swabs, blood cultures, and give paracetamol
Draw around the lesion, give pain relief, oral fluids and antibiotics

Draw around the lesion, give pain relief, oral fluids and antibiotics

36

eczema aetiology and risk factors

Atopy: hayfever, food allergies, asthma
Urban environment, small family (hygiene hypothesis)
Type I reaction (IgE-mediated): atopic dermatitis
Type IV reaction (T cell mediated): contact dermatitis

37

eczema presentation

Itchy, dry skin affecting FLEXURES (usually)
In small infants, can affect face and extensor surfaces
Lichenification (chronic itching)

38

describe atopic dermatiits

‘lichenification’/lichen simplex
Flexures
Atopy
type I reaction

39

describe seborrheic dermatitis

Yellow, greasy scales
Can cause nappy rash
Adults: dandruff, plaques on nasolabial folds, eyebrows
Associated with malassezia yeasts

40

describe contact dermatitis

Nickel (chromate, perfumes, latex, plants) hypersensitivity
type IV reation

41

describe dyshidrotic/pompholyx eczema

Vesicles/blisters
Hands and feet
Related to sweating (hot weather

42

Describe discoid/nummular eczema

Scattered, round patches
Itchy
Hx: atopic eczema, skin injury

43

describe Eczema herpeticum

Herpes simplex infection in eczema sufferer
MEDICAL EMERGENCY
ADMIT

44

eczema invetsigations

Atopic eczema: not normally needed (clinical diagnosis)
Contact dermatitis: skin patch testing (allergen applied to skin for 48h);
positive result = red raised lesion

45

psoriasis aetiology/risk factors

genetic and environmental (complex); triggers include smoking, alcohol, stress

46

psoriasis presentation

Red/silver, scaly plaques, EXTENSOR SURFACES
Can be itchy or painful
Nail pitting, onycholysis
Symmetrical polyarthritis (looks like rheumatoid arthritis)

47

psoriasis signs on examinaiton

Koebner phenomenon: lesions appear in traumatised skin
Auspitz sign: removal of scale --> bleeding

48

psoriasis subtypes

nail
- pitting
- oncholysis
- subungal
- hyperkeratosis

chronic plaque
- silver scales

palmar plantar
- red, dry, thick skin
- fissures

psoriatic arthritis
- telescoping

49

palmar plantar pustular psoriasis associations

smoking, middle-aged women, autoimmune thyroid disease

50

describe psoristic guttate

After strep throat
‘Salmon pink’
Drop-like lesions

51

describe erythroderma psoriasis

Generalised red, inflamed skin
1/3 cases due to worsening psoriasis

52

erythema multiforme aetiology

Infection: viral (herpes simplex virus), bacterial (mycoplasma, chlamydia), fungal (histoplasmosis),
Pregnancy
Drugs: sulphonomides, penicillin
Inflammation: rheumatoid arthritis, SLE, sarcoid
Malignancy: leukaemia, lymphoma, myeloma

53

erythema multiforme presentation

Prodromal symptoms
Target lesions: itching, burning, painful
May fade --> pigmentation
Target lesions: rim of erythema surrounding a paler area
Precipitating factor only identified in 50%

54

Stevens-Johnson syndrome definition

affects more than two mucosal sites (conjunctiva, lips, mouth, oesophagus…)

55

SJS presentation

Systemically unwell: sore throat, fever, cough, headache, diarrhoea and vomiting
Shock: hypotension, tachycardia

56

SJS and EM investigations

Usually clinical diagnoses
FBC: white cells ++
ESR, CRP ++
HSV serology, etc.
Throat swab
CXR (sarcoid, atypical pneumonia)

57

A 12-year-old girl presents with dry, itchy skin that involves the flexures in front of her elbows and behind her knees. She has symptoms of hay fever and was diagnosed with egg and milk allergy at 6 months old. Her mother has asthma.

What is the most likely diagnosis?
Seborrheic dermatitis
Atopic dermatitis
Psoriasis (chronic plaque)
Psoriasis (guttate)
Urticaria

Atopic dermatitis

58

An otherwise healthy 23-year-old man complains of sore red lesions on his extremities which have a central clearance (targetoid). These appeared after a recurrence of his ‘coldsores’.

What is the diagnosis?
Erythema multiforme
Chicken pox
Herpes simplex virus
Stevens-Johnson’s syndrome
Toxic epidermal necrolysis

Erythema multiforme