Dermatology

Question 1

Causes of striae

Answer 1

1. Rapid growth in adolescence
2. Expansion of skin over breasts and abdomen in pregnancy and obesity
3. increased muscle size in body builders (E.g. shoulders)
4. Increased glucocorticoids leading to dermal atrophy (Cushing’s, exogenous steroids)
5. Marfan’s syndrome

Question 2

Causes/associations of erythema nodosum

Answer 2

Sarcoid
Inflammatory bowel disease
Mycoplasma infections
Fever
Arthropathy
Sulphonamides
Oral contraceptives

Question 3

Treatment of scabies

Answer 3

Permethrin or malathion

Question 4

Treatment of cavernous haemangioma (AKA cavernous venous malformation)

Answer 4

Systemic or local steroids, sclerosants and/or laser therapy

NOT surgical excision

Question 5

Management of psoriasis

Answer 5

Topical corticosteroids, tar cream (dithronol - more likely to produce prolonged remission)
Immunosuppresants if resistant (MTX, cyclophosphamide, AZA)

Question 6

Types of candida infection

Answer 6

Oral thrush
Angular chelitis
Vulvovaginal candidiasis
Intertrigo (between skin folds)
Chronic paronychia (nail fold)
Onycomycosis

Question 7

Diseases caused by malassezia fungi

Answer 7

Pityriasis versicolour
Malassezia folliculitis
Seborrheic dermatitis

Question 8

Treatment of malassezia diseases

Answer 8

topical or antifungal agents

Seborrheic dermatitis can also be treated with topical steroids

Question 9

Classic presentation of candida infections

Answer 9

Erythematous

Satellite lesions

Question 10

Diseases caused by dermatophyte fungi (what fungi are they)

Answer 10

Ringworm fungi: microsporum, trichophytum or epidermophyton

tinea capitis
tinea corporis
tinea pedis
tinea unguium

Question 11

Appearance of dermatophyte infections

Answer 11

round or oval red scaly patches
- often less red and scaly in the centre

Tinea capitis: combination of scale and bald patches

Question 12

Pathogens responsible for most tinea corporis

Answer 12

Trichophytum rubrum
Micosporum canis (from cats and dogs)
T verrucosum (from cattle)

Question 13

Definition of acne vulgaris

Answer 13

The most common cutaneous disorder affecting adolescents and young adults involving hyperkeratinisation, increased sebum production, infection and inflammation of the pilosebaceous follicles

Question 14

Bacteria implicated in acne vulgaris

Answer 14

Propionibacterium acnes

Question 15

Management of acne vulgaris

Answer 15

Investigate for hyperandrogenism in females
Mild:
- topical anti-acne (benzoyl peroxide, tretinoin gel)
- low dose COCP
- antiseptic or keratolytic washes containing salicylic acid
- light/laser therapy
- clindamycin wash

Moderate: as above PLUS

• tetracycline for 6m (or erythromycin or trimethoprim if doxy-intolerant)
• anti-androgen therapy (cyproteron acetate + ethinylestradiol and/or spironolactone)
• isotretinoin if persists

SEVERE:

• refer to derm
• oral antibiotics, higher dose
• oral isotretinoin

Question 16

Pityriasis rosea clinical features

Answer 16

Herald patch

• single plaque 1-20d before generalised rash
• oval pink or red 2-5cm diameter
• scale trailing just inside edge of lesion

Secondary rash:
- more scaly patches or plaques on chest and back
- tend to be smaller than herald patch
- oval in shape
- dry surface
- Follow Langers lines
DOES NOT INVOLVE FACE, SCALP, PALMS, or SOLES
Usually not itchy

Question 17

Management of pityriasis rosea

Answer 17

Bathe or shower with plain water and bath oil/soap substitute
Moisturising creams
Exposer skin to sunlight (avoid burning though)
Topical steroids may reduce itch while waiting for resolution

Acyclovir or erythromycin may speed up clearance but are not PBS listed