Skin Infections and Infestations

Question 1

Presentation of tinea (4)

Answer 1

round, scaly lesion

has central clearing

itchy

affects scalp, body, groin, feet, nails

Question 2

Rx of tinea (3)

Answer 2

skin: terbinafine or topical ketoconazole/miconazole
scalp: griseofulvin or terbinafine
nails: terbinafine

Question 3

Presentation of candida (4)

Answer 3

pink+ white patches

satellite lesions

moist

mouth, vagina, skin folds, toe webs

Question 4

Rx of candida (2)

Answer 4

Mouth: nystatin

vagina: clotrimazole cream/pessary

Question 5

Cause of pityriasis versicolor

Answer 5

malasezzia furfur

Question 6

Presentation of prityriasis versicolor (5)

Answer 6

commonly hot/humid environments

circular hyper/hypopigmented patches

white scale

itchy

commonly affects trunk and back of neck

Question 7

Ix for pityriasis versicolor

Answer 7

“spaghetti and meatballs” appearance w. KOH stain

Question 8

Rx of pityriasis versicolor (2)

Answer 8

selenium sulphate or ketoconazole shampoo

Question 9

Presentation of impetigo (3)

Answer 9

peak age of 2-5yrs

honey-coloured crust on erythematous base

commonly affects mouth/face

(staph aureus)

Question 10

Rx of impetigo (2)

Answer 10

mild: topical fusidic acid/mupirocin
severe: fluclox PO

Question 11

Presentation of erysipelas (3)

Answer 11

sharply defined, superficial infection by strep pyogenes

commonly affects face

high fever+ raised WCC

Question 12

Rx of erysipelas (2)

Answer 12

IV benpen

Penicillin V+fluclox PO

Question 13

Features of cellulitis (2)

Answer 13

acute infection of skin and soft tissues

by beta haemolytic strep and staph aureus

Question 14

Presentation of cellulitis (4)

Answer 14

deeper and less well-defined as erysipelas

pain, swelling, erythema and warmth

systemic upset

+/- lymphadenopathy

Question 15

Rx of cellulitis (3)

Answer 15

empirical: fluclox IV

confirmed strep: benpen or pen V

pen allergic: clindamycin

Question 16

Rx of warts (5)

Answer 16

expectant

destructive:

• topical salicylic acid
• cryotherapy
• podophyllin
• imiquimod

Question 17

Features of molluscum (3)

Answer 17

pox virus

pink papules w. umbilicated central punctum

resolve spontaneously

Question 18

Features of herpes zoster/shingles (4)

Answer 18

recurrent VZV infection

dermatomal distribution of cropping vesicles and crusts:
-thoracic 50%, opthalmic 20%

may> post-herpetic neuralgia

Rx w. acicovir/famciclovir if severe

Question 19

Features of HSV infection (5)

Answer 19

gingivostomatitis or recurrent genital/oral infections

triggered by infection (CAP), sunlight, immunosuppresion

can complicate eczema>eczema herpeticum

grouped, painful vesicles on an erythematous base

aciclovir/famciclovir indicated if immunosuppressed or recurrent genital herpes

Question 20

Features of pityriasis rosea (3)

Answer 20

HHV-6/7

herald patch preceds rash, mainly on trunk

Question 21

Features of scabies infection (3)

Answer 21

sarcoptes scabei

highly contagious: spread by direct contact

female mite digs burrows into skin and lays eggs

Question 22

Presentation of scabies (5)

Answer 22

burrows

hypersensitivity rash: eczematous, vesicles

extreme pruritus

commonly affects finger webs

also affects axillae, groin and umbilicus

Question 23

Mx of scabies (4)

Answer 23

permethrin cream applied from neck down for 24hrs

2nd line: malathion

3rd line: oral ivermectin

Rx all members of household

Question 24

Presentation and Rx of headlice (4)

Answer 24

presents w. itch, papular rash at nape of neck

Rx w. malathion and combing