Dermatology

Question 1

When might you see lichenified skin?

Answer 1

As a result of chronic itching of eczema

Question 2

What is the ABCDE for taking a history of a skin lesion?

Answer 2

A - asymmetry
B - border irregularity
C - colour variation
D - diameter 
E - evolution over time

Question 3

What is a macule?

Answer 3

A flat area of altered skin colour (impalpable)

Question 4

What is a papule?

Answer 4

An elevated, palpable skin lesion

Question 5

What is a nodule?

Answer 5

An elevated, palpable skin lesions >5mm

Question 6

What is a vesicle?

Answer 6

A fluid-filled blister

Question 7

Palpable purpura are characteristic of what group of conditions?

Answer 7

Vasculitides

Question 8

How does tinea corporis typically present?

Answer 8

Scaly, annular lesions on the body that are itchy & have an area of central clearing

Question 9

What is the management of tinea?

Answer 9

• Topical agent, eg/ imidazole or terbinafine creams
• Oral griseofulvin for extensive infections
• Tinea of the scalp needs prolonged treatment with oral antifungals

Question 10

What are some specific treatments of molluscum contagiosum?

Answer 10

• Topical irritants - eg/ salicylic acid
• Topical immunostimulants
• Destructive methods

Question 11

Which pathogen usually causes folliculitis?

Answer 11

Staph. aureus

Question 12

Which pathogen usually causes impetigo?

Answer 12

Staph. aureus

Question 13

What is the treatment of impetigo?

Answer 13

Anti-staph antibiotics: flucloxacillin or cephalexin

Question 14

Which organism commonly causes cellulitis?

Answer 14

Grp A Streptococcus

Question 15

What are 3 features of eczema on history?

Answer 15

• Itchy rash
• Located in flexures
• Worse in winter
• Pt may also have asthma & hayfever
• Family Hx of eczema

Question 16

What are some of the triggers of eczema?

Answer 16

• Stress & anxiety
• Irritants (soap)
• Allergy
• Heat
• Infection
• Genetic predisposition (Filaggrin mutation)

Question 17

What does discoid eczema look like?

Answer 17

Annular disc-like patches of eczema (mimics psoriasis & tinea)

Question 18

What is asteatotic eczema?

Answer 18

Eczema that is worst on the front of the legs of elderly patients, and flares up in winter

Question 19

What is pompholyx?

Answer 19

Vesicular hand & foot eczema

Question 20

What is the treatment of diffuse erythrodermic eczema?

Answer 20

Intense topicals & systemic immunosuppression

Question 21

What is eczema herpeticum & how is it treated?

Answer 21

Secondary infection of eczematous skin with HSV virus. Tx: systemic antiviral treatment + opthalmology assessment if eye involvement

Question 22

What are the lifestyle modifications for atopic eczema?

Answer 22

• Avoid soap
• Regular emollient
• Warm, not hot showers

Question 23

What are specific eczema treatments?

Answer 23

• Topical steroids
• Non-steroid anti-inflammatory creams (eg/ pimecrolimus)
• Treat suspected infections with antibiotics
• Phototherapy with UVB
• Systemic immunosuppression

Question 24

What are 3 features of eczema on examination?

Answer 24

• Erythematous, ill-defined scaly patches
• Rash in flexural areas
• Lichenified skin in chronic eczema

Question 25

What are 3 features of psoriasis on history?

Answer 25

- Mostly on extensor surfaces - Symmetrical involvement - Well-demarcated plaques - Some itch - Gradually worsening - Better with UV exposure

Question 26

What are 3 features of psoriasis on examination?

Answer 26

- On extensor surfaces - Well demarcated plaques - Silvery-white scale - Very erythematous/salmon pink - Scalp involvement

Question 27

How does flexural & genital psoriasis differ from typical psoriasis?

Answer 27

Flexural & genital psoriasis is less scaly, and has a 'glazed' appearance (often confused with tinea)

Question 28

What is post-streptococcal guttate psoriasis?

Answer 28

Occurs 1-2 weeks after Strep infection - sudden onset of small plaque psoriasis

Question 29

What are the treatment options for psoriasis?

Answer 29

- Topical - steroids, tars, calcipotriol, dithranol, emollients - Phototherapy - narrowband UVB treatment - Systemic - oral acitretin, methotrexate, cyclosporin A, biologic agents

Question 30

What are the 4 components of acne?

Answer 30

1. Abnormal keratinization of sebaceous duct 2. Colonization with bacteria 3. Increase in androgen levels leading to increased sebum production 4. Inflammation

Question 31

What are the topical treatments for acne?

Answer 31

Keratolytics, comedolytics, anti-bacterials

Question 32

What are some systemic treatments for acne?

Answer 32

Antibiotics (doxycycline, minocycline), anti-androgenic OCP (females), systemic retionoids (isotretinoin)

Question 33

How long is the treatment course of systemic isotretinoin for acne?

Answer 33

6-12 months (specialist use only)

Question 34

What are some of the adverse effects of systemic isotretinoin?

Answer 34

Teratogenic, dryness, photosensitivity, controversial association with depression

Question 35

What are some triggers of vascular rosacea?

Answer 35

Sunlight, alcohol, hot foods, spicy foods, emotion, heat, topical steroids

Question 36

What are some clinical features of rabies?

Answer 36

- Spares face & head in adults - Intensely itchy rash, starting on hands & feet - Itch is worse at night - Spreads to genital areas, generalised body rash - Incubation period 4-6 weeks

Question 37

What are the general management considerations for scabies?

Answer 37

- Treat all close contacts - Treat index case at diagnosis & again at 1 week - Post-scabetic itch can take weeks to settle

Question 38

What is the topical treatment of scabies?

Answer 38

-5% permethrin cream from neck down

Question 39

Which is the most commonly diagnosed skin cancer?

Answer 39

BCC (67%)

Question 40

What are the 2 precursor lesions to SCC?

Answer 40

- Solar (actinic) keratosis | - Bowen's disease (SCC in situ)

Question 41

What is the typical description of an SCC?

Answer 41

Erythematous, hyperkeratotic papule or nodule that may bleed or ulcerate & may be tender

Question 42

What is the typical description of a BCC?

Answer 42

Pearly nodules often containing prominent, dilated subepidermal blood vessels (telangiectasias), may bleed

Question 43

Which non-pigmentous skin cancer is more likely to metastasize?

Answer 43

SCC

Question 44

How are solar keratoses described?

Answer 44

Erythematous, scaly lesions commonly found on the dorsum of hands

Question 45

What is the treatment of solar keratoses?

Answer 45

Options include: - Cryotherapy - Topical - Surgical excision

Question 46

What are some features of Bowen's disease?

Answer 46

- Full thickness epidermal dysplasia, with no invasion - Commonly seen in lower limbs - Risk of malignant transformation to SCC is 3-5% - Often asymptomatic, but can be itchy, painful or may bleed

Question 47

What is a benign junctional naevus?

Answer 47

A naevus located at the epidermal side of the dermo-epidermal junction

Question 48

What is a benign compound naevus?

Answer 48

A naevus located in the epidermis & the dermis

Question 49

What is a benign intradermal naevus?

Answer 49

An intradermal naevus - usually pale in colour

Question 50

What are some features of a benign mole?

Answer 50

- Small - Evenly coloured - Regular edges - Symmetrical - Does not change with time

Question 51

Name 4 risk factors for melanoma.

Answer 51

- Multiple dysplastic naevi (>5) - Past history of melanoma - Family Hx - History of blistering sunburn - Type 1 skin - Freckling - Red hair - Immunosuppression

Question 52

What are some features of melanoma?

Answer 52

- Itch - Increasing size - Irregular border - Colour variation - Inflammation - Crusting or bleeding