Dermatology

Question 1

What age does acne vulgaris often affect?

Answer 1

People during puberty and adolescence.

Most people are affected at some point during their lives.

Question 2

What is the cause of acne vulgaris?

Answer 2

• caused by chronic inflammation, with or without infection, in the pilosebaceous unit (pockets in the skin)
• pilosebaceous units are tiny dimples in the skin that contain hair follicles and sebaceous glands
• sebaceous glands produce sebum (natural skin oil, waxy)
• acne results from increased sebum production, trapping of keratin (dead skin cells) and blockage of the pilosebaceous unit.

Question 3

What increases the production of sebum and what can be used to improve this?

Answer 3

Androgen hormones increase production of sebum so acne is exacerbated by puberty.

Anti-androgenic hormonal contraception improves this.

Question 4

What are swollen and inflamed pilosebaceous units called?

Answer 4

Comedeones.

Question 5

What bacteria is felt to play an important role in acne?

Answer 5

Propionibacterium acnes.

Thought that excessive growth of this bacteria can exacerbate acne.

Many acne treatments aim to reduce these bacteria.

Question 6

How does acne vulgaris present?

Answer 6

• significant variation in severity
• red, inflamed and sore ‘spots’ on the skin
• typical distribution across the face, upper chest and upper back

Question 7

What are comedones?

Answer 7

Skin coloured papules representing blocked pilosebaceous units.

Question 8

What are blackheads?

Answer 8

Open comedones with black pigmentation in the centre.

Question 9

What are ‘ice pick scars’?

Answer 9

Small indentations in the skin that remain after acne lesions heal.

Question 10

What are hypertrophic scars?

Answer 10

Small lumps in the skin that remain after acne lesions heal.

Question 11

What is the aim of treatment?

Answer 11

• reduce symptoms of acne
• reduce risk of scarring
• minimise psychosocial impact of the condition

Question 12

What else must be explored alongside the acne symptoms?

Answer 12

• psychosocial burden

- potential anxiety and depression associated with condition

Question 13

What is the management for acne vulgaris?

Answer 13

• no treatment if mild
• topical benzoyl peroxide
• topical retinoids
• topical abx e.g. clindamycin
• oral abx e.g. lymecycline
• OCP

Question 14

How does topical benzoyl peroxide work?

Answer 14

• reduces inflammation
• unblocks skin
• toxic to P.acnes bacteria

Question 15

How do topical retinoids work?

Answer 15

• chemicals related to vitamin A

- slow sebum production

Question 16

What is the risk of retinoids?

Answer 16

• Highly teratogenic

- females of childbearing age require effective contraception

Question 17

What must be prescribed alongside topical abx to reduce bacterial resistance?

Answer 17

Benzoyl peroxide

Question 18

What is an effective last-line option?

Answer 18

• oral retinoids for severe acne e.g. isotretinoin (roaccutane)
• careful follow-up, monitoring, reliable contraception

Question 19

How does oral isotretinoin work?

Answer 19

• reduces sebum production
• reduces inflammation
• reduces bacterial growth
• prescribed under expert supervision by dermatologist

Question 20

How long before becoming pregnant must patients stop isotretinoin?

Answer 20

At least 1 month before becoming pregnant.

Question 21

What are the side effects of isotretinoin?

Answer 21

• dry skin/lips
• photosensitivity of skin to sunlight
• depression, anxiety, aggression, suicidal ideation
• rarely Stevens-Johnson syndrome, toxic epidermal necrolysis

Question 22

What must patients be screened for prior to starting isotretinoin?

Answer 22

• mental health issues

Question 23

What is impetigo?

Answer 23

A superficial bacterial skin infection.

It occurs when bacteria enter via a break in the skin = may be in otherwise healthy skin or related to eczema or dermatitis.

Question 24

What bacteria most commonly causes impetigo?

Answer 24

Staphylococcus aureus

Question 25

What is characteristic of a Staphylococcus skin infection?

Answer 25

'golden crust'

Question 26

What bacteria less commonly causes impetigo?

Answer 26

Streptococcus pyogenes.

Question 27

Is impetigo contagious?

Answer 27

Yes - children should be kept off school during the infection.

Question 28

What can impetigo be classified as?

Answer 28

1) Non-bullous | 2) Bullous

Question 29

Where does non-bullous impetigo typically occur?

Answer 29

Around the nose or mouth.

Question 30

What happens to the exudate in non-bullous impetigo?

Answer 30

Exudate from the lesions dries to form a 'golden crust'. They are often unsightly but do not usually cause systemic symptoms or make the person unwell.

Question 31

What is the first-line treatment for localised non-bullous impetigo?

Answer 31

Hydrogen peroxide 1% antiseptic cream

Question 32

What else can be used for non-bullous localised impetigo?

Answer 32

Topical abx: - fusidic acid 2% - mupirocin 2% (if fucidin acid resistant)

Question 33

What can be used to treat more widespread or severe non-bullous impetigo?

Answer 33

Oral flucloxacillin

Question 34

What general advice should be given about non-bullous impetigo?

Answer 34

- advice to avoid spreading the impetigo - avoid touching or scratching the lesions - hand hygiene - avoid sharing face towels and cutlery - children must be off school until all lesions have healed or have been treated with abx for at least 48 hours