Dermatology

Question 1

What forms of emolients are there?

Answer 1

Creams, gels, lotions, ointment

Question 2

What is a gel?

Answer 2

Thickened aqueous solutions with HMWP

Question 3

What is a lotion?

Answer 3

suspension of medication in water/alcohol/liquid

Question 4

What is a cream?

Answer 4

semi-solid emulsion of oil and water containing emulsifier and preservative

Question 5

What is an ointment?

Answer 5

semi-solid mix of grease and oil containing soft paraffin

Question 6

What is the treatment of eczema?

Answer 6

1. Avoidance and soap substitutes
2. Emollient
3. Topical steroids for flare ups
4. Calcineurin inhibitors
5. Systemic immunosuppressants
   Antihistamines at night sometimes

Question 7

What is the treatment of psoriasis?

Answer 7

Topical:

1. Emollients
2. Topical steroid and vitamin D
3. Coal tar if widespread
4. Immunosuppressants

Other:
Phototherapy
Methotrexate (DMARD)
Biologics

Question 8

How does dermatitis herpetiformis present?

Answer 8

Itchy blistering rash, associated with coeliac

Question 9

What is dermatitis herpeticum?

Answer 9

When eczema gets infected with HSV, can be lethal

Question 10

Pemphigus vs pemphigoid

Answer 10

Pemphigus: nikolsky sign positive, IgG against desmogleins

Pemphigoid: IgG against hemidesmosomes, sub-epidermal

Question 11

What are warts caused by?

Answer 11

HPV

Question 12

Describe immunofluorescence of pemphigus and pemphigoid

Answer 12

pemphigoid: linear IgG
pemphigus: scattered IgG

Question 13

What strains of HPV cause what?

Answer 13

1-4: warts
6 and 11: genital warts
16 and 18: cancer

Question 14

Histology of warts?

Answer 14

Focal epidermal hyperplasia with hyperkeratosis, parakeratosis and papillomatosis

Question 15

Histology of psoriasis?

Answer 15

Parakeratosis (cell nuclei within stratum corneum) and thickened projections of the prickle cell layer of keratinocytes (psoriasiform hyperplasia). There is no granular layer

Question 16

What is the extra layer in thick skin (sole of foot and palms of hands)?

Answer 16

Stratum lucidum - translucent under microscope, made of dead cells

Question 17

Enzyme defect in porphyria cutanea tarda?

Answer 17

uroprophyrogen decarboxylase

Question 18

What builds up in PCT?

Answer 18

uroporphyrogen

Question 19

Presentation of PCT?

Answer 19

Blistering, fragility, hyperpigmentation, hypertrichosis

Question 20

Investigation for PCT?

Answer 20

Wood lamp

Question 21

Erythropoietic porphyria enzyme defect?

Answer 21

ferrochelatase

Question 22

What build up in EP?

Answer 22

protoporphyrin ix

Question 23

what is a classic presentation of EP?

Answer 23

child crying in the sunlight :(

Question 24

What is the enzyme defect in acute intermittent porphyria?

Answer 24

PBG deaminase

Question 25

What builds up in AIP?

Answer 25

hydroxymethylbilane

Question 26

Risk factors for skin cancer?

Answer 26

``` constant sun exposure - SCC burning and recovering - BCC, MM Type 1 skin Moles pre-cancerous lesions Immunosuppression Getting burnt as a child lol FHx Radiation treatment ```

Question 27

Acne treatments?

Answer 27

1. topical retinoid 2. benzoyl peroxide 3. topical abx (tetracyclines) 4. oral abx or oral isotretinoin

Question 28

Side effects of acne treatment?

Answer 28

Dry skin, worse before better

Question 29

difference between rosacea and acne?

Answer 29

Blackheads only occur in acne, flushing and redness in rosacea

Question 30

Treatment for rosacea

Answer 30

Metronidazole

Question 31

What two distinct diseases does HZV cause?

Answer 31

Chickenpox and shingles

Question 32

What is Ramsay hunt syndrome?

Answer 32

reactivation of HZV in geniculate ganglion of CNVII - old people with hearing loss

Question 33

What sign is seen in ophthalmic HZV?

Answer 33

Hutchinson sign (tip of nose indicates high chance of ocular involvement)

Question 34

What is molluscum contagiosum?

Answer 34

highly contagious virus common in children or spread through sexual contact, not painful but itchy, self limiting but takes months to go away

Question 35

What is epidermolysis bullosa?

Answer 35

Breakdown of anchoring between epidermis and dermis