Dermatology

Question 1

What is the presentation of erythropoetic protoporphyria?

Answer 1

Childhood or pregnancy

Oedema, fragility, blistering and petechia on sun-exposed areas

Question 2

What is the mechanism of erythropoetic protoporphyria?

Answer 2

Failure of ferrochellatase enzyme leads to protoporphyrin build up

Question 3

What is the treatment of erythropoeitc protoporphyria?

Answer 3

Visible light protection measures
Genetic counselling
6 monthly LFTs and porphyrins

Question 4

What are the causes of porphyria cutaenea tarda?

Answer 4

Alcohol
Hepatitis
Oestrogens
Haemochromatosis

Question 5

What is the presentation of porphyria cutanea tarda?

Answer 5

Blisters, skin fragility, hyperpigmentation, hypertrichosis, solar urticaria and morphoea on sun exposed areas

Question 6

What is the treatment of porphyria cutanea tarda?

Answer 6

Treat the underlying cause

Question 7

What is the first line treatment of acne?

Answer 7

Benzoyl peroxide

Question 8

What is the first line treatment of rosacea?

Answer 8

Topical metronidazole

Question 9

What are exclamation mark hairs a sign of?

Answer 9

Alopecia areata

Question 10

What are the side effects of isotretinoin (roaccutane)

Answer 10

Dry hair and skin
Teratogenicity
Hyperlipidaemia
Raised liver enzymes
Depression - contraindicated in patients with positive Hx

Question 11

What is used to treat scabies?

Answer 11

Malathion lotion

Question 12

What is pyoderma gangrenosum associated with?

Answer 12

IBD
Haematological disease
RA

Question 13

What enzyme is impaired in acute intermittent porphyria?

Answer 13

PBG deaminase

Question 14

Where does vitamin D metabolism occur?

Answer 14

Prickle cell layer

Question 15

What is the function of collagen, where in the skin is it and what is it produced by?

Answer 15

Tensile strength
In the dermis
Produced by fibroblasts

Question 16

What is the function of impedin?

Answer 16

Allows organism to avoid host defence mechanisms

Question 17

What is the function of modulin?

Answer 17

Alters host immune response - indirect damage to host

Question 18

How is ringworm diagnosed?

Answer 18

Skin scraping for microscopy and culture and Wood’s light

Question 19

How is tuberous sclerosis inherited?

Answer 19

Autosomal dominant

Question 20

What are features of tuberous sclerosis?

Answer 20

Ash leaf spots
Epilepsy
Periungum scleroma

Question 21

How is neurofibromatosis type I inherited?

Answer 21

Autosomal dominant

Question 22

What does rosacea look like?

Answer 22

Erythema
Telangectasia
Papules
Pustules
Lymphoedema

Question 23

Why are creams more likely to cause contact sensitisation than ointments?

Answer 23

They contain preservatives

Question 24

How do steroids get into cells?

Answer 24

Diffuse across cell membrane - lipophilic

Question 25

What is dithranol used to treat? What is a side effect?

Answer 25

Psoriasis | May stain clothing

Question 26

What is a dermatofibroma?

Answer 26

Benign papule or nodule due to proliferation of fibroblasts

Question 27

What does a superficial BCC look like?

Answer 27

Slightly scaly irregular plaque, thin translucent rolled border, microerosions

Question 28

Where is Breslow thickness measured from?

Answer 28

Granular cell layer to deepest point of melanoma

Question 29

What are the Breslow categories?

Answer 29

<1mm 95% 5y prognosis >4mm 50% 5y prognosis Metastases 5% 5y prognosis

Question 30

Buzzword - cobblestoning

Answer 30

Chronic lymphoedema

Question 31

Signs of pityriasis rosacea?

Answer 31

Hearld patch | Salmon pink macules

Question 32

What do horn cysts on histology indicate?

Answer 32

Seborrhoeic keratosis/basal cell papilloma

Question 33

What does picket fencing around nests of cells on histology indicate?

Answer 33

Nodular BCC

Question 34

Causes of erythema nodosum?

Answer 34

OCP Sarcoidosis IBD Tb

Question 35

What does intense erythema on the cheek of a child suggest?

Answer 35

Slapcheek - parovirus B19

Question 36

What is acanthosis nigricans a sign of?

Answer 36

Addison's disease | Insulin resistance