Dermatology

Question 1

4 factors involved in the formation of acne lesions

Answer 1

1. increased sebum production, influenced by androgens
2. keratin and sebum plug the hair follicle and accumulate leading to hyperkeratosis (comedy formation)
3. C. Acnes proliferates in the sebaceous follicle releasing enzymes and stimulates release of pro inflammatory cytokines
4. inflammatory response

Question 2

comedonal acne

Answer 2

open and closed comedones

Question 3

inflammatory acne

Answer 3

papules and pustules

Question 4

Nodulocystic acne

Answer 4

Nodules and cysts

Question 5

when to refer a patient with acne to dermatology

Answer 5

Patients with difficult to control or the presence of scarring.

Question 6

MOA topical retinoids

Answer 6

Vitamin A derivative that acts by normalizing the desquamation of follicular epithelium to prevent formation of new comedones

Question 7

Side effects of topical retinoids

Answer 7

Dryness
pruritus
erythema
scaling
photosensitivity

Question 8

Patient counselling for topical retinoids

Answer 8

Use suncream and protective clothing
do not apply at same time as benzoyl peroxidase
not to be used while pregnant

Question 9

MOA benzoyl Peroxidase

Answer 9

antibacterial and comedolytic properties.
Acts via the generation of free radicals that oxidase proteins in the P. Acnes cell wall

Question 10

Side effects of benzoyl peroxide

Answer 10

Bleaching of hair, coloured fabric and carpet
skin irritation

Question 11

MOA topical antibiotics

Answer 11

reduces number of C. acnes and reduce inflammation in inflammatory acne
(erythromycin 2% and clindamycin 1%)

Question 12

Side effects topical antibiotics

Answer 12

irritation and dry skin

Question 13

patient counselling for topical antibiotics

Answer 13

if using as combination therapy use on alternate days to retinoid or benzoyl peroxide to start with
use with a moisturizer
should be used in combination with benzoyl peroxide to prevent development of antibiotic resistance in mild to moderate acne

Question 14

patient with acne counselling

Answer 14

set expectations
Acne treatment targets new lesions not present ones
can take 2-3 months to see effect
therapy should be continued for 8 weeks before response can be evaluated.
Daily use of ceramide-containing moisturizers may improve skin dryness and irritation - can also improve adherence
Overaggressive washing and use of scrubs and astringents exacerbate acne
low glycemic load diets may improve acne by reducing androgen-induced sebaceous gland activity and keratinocyte growth associated with increased insulin and IGF-1 levels

Question 15

first line Abx treatment for moderate to severe acne.

Answer 15

Tetracyline, doxycycline, minocycline
Macrolides are second line
Should be combined with benzoyl peroxide to prevent Abx resistance

Question 16

MOA Isotretinoin

Answer 16

a retinoid acid derivative that targets all 4 pathpphysioloc factor involved in acne.
Used for severe nodulocystic acne that has failed other therapies.

Question 17

Side effects of Isotretinoin

Answer 17

Xerosis (dry skin)
Chelilitis (chapped lips)
Elevated liver enzymes
Hypertriglyceridemia
depression/suicide
When combined with tetracycline Abx there is a small risk of developing pseudotumor cerebri and therefore should not be used together

Question 18

treatment for hormonal acne

Answer 18

spironolactone: androgen-receptor blocker
oral contraceptives: surpresses LH production, increase sex hormone binding global, inhibit 5-alpha reductase, block androgen receptor.

Question 19

morphology of acne rosacea

Answer 19

easy flushing, erythema, telangietasias, papule and pustules, and/or phymatous changes (red, swollen distorted skin - most often seen on the nose)
may have ocular involvement

Question 20

Acne rosacea triggers

Answer 20

Alcohol
sunlight
heat including hot beverages
spicy food
emotional stress