Acne Vulgaris

Question 1

Describe the pathophysiology of acne vulgaris. (4)

Answer 1

1. Accumulation of epithelial cells and keratin causes narrowed hair follicles
2. Accumulation of shed keratin and sebum
   a. Blockage of sebaceous gland
3. Infection with P. acnes
   a. Mild inflammation (may progress)
4. Severe inflammation will result in scarring

Question 2

What bacterium is associated with acne vulgaris?

Answer 2

Propionibacterium acnes

Question 3

List 3 causes of acne vulgaris.

Answer 3

Increased production of sebum (due to androgens)
Increased sebum viscosity (due to androgens)
P. acne infection

Question 4

List 7 subtypes of acne vulgaris.

What other condition is often classified with acne?

Answer 4

Papulopustular
Nodulocystic
Comedonal
Steroid induced acne
Acne fulminans
Acne agminata
Acne rosacea

Acne inversa (hidradenitis suppurativa)

Question 5

Define acne inversa (or hidradenitis suppurativa).

Answer 5

A chronic, inflammatory, scarring condition involving the intertriginous skin of the axillary, inguinal, infra/intermammary, genital and perineal areas of the body

Question 6

Briefly describe the typical features of acne inversa. (4)

How would you treat acne inversa?

Answer 6

FEATURES:
Painful boils
Abscesses
Sinuses
Spontaneous resolution is rare

TREATMENT:
Surgical excision

Question 7

List 7 clinical features of acne vulgaris.

Of these, which are more associated with long term acne?

Answer 7

Papules
Pustules
Comedones
Erythema

LONG TERM FEATURES:
Nodules
Cysts
Scarring

Question 8

Which scale is used to grade the severity of acne vulgaris?

Briefly describe it.

Answer 8

Leeds acne grading system

Photographic scale, grades 1-12

Question 9

What are the 3 aims of acne treatment?

Answer 9

Reduce plugging
Reduce bacterial infection
Reduce sebum production

Question 10

How would you treat mild-moderate acne?

Answer 10

1. Reduce plugging:
   a. Topical retinoids
   b. Topical benzoyl peroxide
2. Reduce bacterial infection:
   a. Topical antibiotics
   b. Oral antibiotics
   c. Topical benzoyl peroxide
3. Reduce sebum production:
   a. Anti-androgen hormones

Question 11

What types of antibiotics would you give in acne? Consider:

a) Topical agents
b) Oral agents

Answer 11

TOPICAL ANTIBIOTICS:
Erythromycin
Clindamycin

ORAL ANTIBIOTICS:
Tetracyclines
Erythromycin

Question 12

Describe the mechanism of action of retinoids. (3)

Answer 12

1. Concentrated vitamin A
2. Reduces sebum production and therefore prevents plugging
3. Reduces P. acne infection

Question 13

How would you treat severe acne? (1)

What type of drug is this?

Answer 13

Oral isotretinoin

Oral retinoid

Question 14

What is the standard dose and duration of treatment for oral isotretinoin?

Answer 14

Dose: 1mg/kg

Course: 16 weeks

Question 15

List 4 serious side effects of oral isotretinoin.

Answer 15

Deranged LFTs
Raised lipids
Mood disturbances
Teratogenicity

Question 16

Which 2 measures do you need to take before prescribing oral isotretinoin?

Answer 16

Psychiatric screening (in patients with pre-existing problems)

Pregnancy prevention programme

Question 17

List 3 features of the pregnancy prevention programme.

Answer 17

At least 2 forms of contraception

Pregnancy must be excluded before prescription

Only 4 weeks of isotretinoin can be prescribed at once

Question 18

List 4 side effects of topical agents used in acne.

Answer 18

Irritation
Burning
Skin peeling
Bleaching