Dermatology

Question 1

IgG deposition at the dermo-epidermal junction

Answer 1

bullous pemphigoid

Question 2

Bullous pemphigoid vs pemphigus vulgaris

Answer 2

Oral lesions more common in pemphigus

Question 3

Intercellular deposition of IgG

Answer 3

pemphigus vulgaris

Question 4

symmetrical reticulated, violaceous patches

Answer 4

Livedo reticularis

Due to dilation of capillaries

Idiopathic
Or 2 SLE, malignancy, vasculitis, cholesterol emboli

Question 5

ASOT test for

Answer 5

Streptococcus throat

Question 6

target lesions

Dx?
a/w which drugs?

Answer 6

erythema multiforme

ABx
penicillins
sulphonamides
isoniazid, tetracycline

AEDs
phenytoin, carbamazepine, phenobarbitone

Other
Aspirin, NSAIDs, radiation, pregnancy

Question 7

erythema multiforme

a/w which viruses?

Answer 7

viruses - herpes simplex 1 and 2, hepatitis B, Epstein-Barr virus (EBV), enteroviruses
small agents - Mycoplasma pneumoniae
bacteria - Group A Streptococcus, eosina, and
other - Mycobacterium tuberculosis, histoplasma, coccidioides.

Question 8

Hydroxychloroquine

Indication?

Screen for before starting?

Answer 8

Malaria

Eye toxicity so see ophthalmologist and regular f/up whilst on it

Question 9

indurated plaques on cheeks

the scarring alopecia hyperkeratosis over the hair follicles.

Answer 9

Discoid lupus

Question 10

dermal papules

lesions become larger, annular plaques

on extensors

NOT ITCHY

Answer 10

granuloma annulare

benign inflammatory condition

aetiology unknown

(nb. psoriasis is silvery plaques + itchy)

Question 11

itchy, shiny
violaceous papules

often on extremities

White patch/ ulcer BUCCAL MUCOSA

nail deformity, scarring alopecia

Dx?

Associated with which virus?

Answer 11

Lichen planus

Hep C increases susceptibility

Question 12

pruritic vesicles

elbows, knees, and buttocks

not responded to topical steroids

Answer 12

dermatitis herpetiformis

Question 13

intensely itchy, red, scaling rash which affects his scalp predominantly

patch on chest and beard

Dx?

Rx?

Answer 13

seborrhoeic dermatitis

ketoconazole shampoo

Question 14

On cyclosporin

New hard round lesion on face

Dx?

Answer 14

SCC

Immunosuppression -> SCC and BCC

NB melanoma normally irrgular, pigmented, growing mole +/- bleeding

Question 15

Strep throat 2 weeks ago

Abx for 1 week

now multiple erythematous papules + plaques on trunk and UL with superficial scaling

Dx?

Answer 15

Guttate psoriasis

classically seen two to three weeks after streptococcal infection, and usually resolves spontaneously

Question 16

Starting Dapsone

what do you check for?

Answer 16

G6PD deficiency

absolute CI to dapsone as it can lead to severe haemolytic anaemia

Question 17

Starting cyclosporin

what do you monitor?

Answer 17

BP

can get HTN

Question 18

Condition exacerbated by exposure to light?

acute intermittent porphyria
pellagra
acne vulgaris

Answer 18

Pellagra

Question 19

fragility of sun exposed skin

after mechanical trauma
leading to erosions and bullae
worst on dorsal hands, forearms and face

Answer 19

porphyria cutanea tarda

Question 20

1 week after amoxicillin for UTI

Haematuria
AKI
fever

widespread erythematous rash

Eosinophilia

Answer 20

interstitial nephritis

40-60% of cases due to drug hypersensitivity

Typically B lactam or NSAID

can get liver involvement

Rx = stop drug +/- high dose Pred

Question 21

whitish discolouration up to nail bed of both feet

dermatophyte infection confirmed

Rx?

Answer 21

Terbinafine

first line treatment for fungal nail infection (onychomycosis)

Question 22

generalised erythema and pustule formation

BG psoriasis

Dx?

Answer 22

erythroderma

emergency

admit to hospital

Question 23

Dermatitis herpetiformis associated with?

Answer 23

coeliac disease

Question 24

intensely pruritic vesicles

elbows, knees, buttocks, and scalp

not usually responsive to topical steroids

Answer 24

DH

Give Dapsone (check for G6PD before)

Question 25

itching and blistering of the hands and the forehead

excoriation marks on back of hands

Dx?

Answer 25

Porphyria cutanea tarda