Dermatology

Question 1

What are the indications for emollients?

Answer 1

Dry skin, eczema, psoriasis

Question 2

What are some examples of emollients?

Answer 2

Light creams: aqueous, dermol, cetraben, diprobase, dermol 500
Greasy preparations: hydromol, epaderm, emulsifying ointment, 50% white soft paraffin in liquid paraffin
(Dermol products also contain benzalkonium chloride and can be useful in secondary infection)

Question 3

What are side effects of emollients?

Answer 3

These are uncommon. They include contact dermatitis and being fire hazards (emulsifying ointment and paraffin products).

Question 4

What are soap substitutes used for?

Answer 4

Useful in dry, itchy skin conditions. Aqueous cream is satisfactory.

Question 5

What are the indications for topical corticosteroids?

Answer 5

Inflammatory conditions such as insect bites, eczema, localised psoriasis

Question 6

What is a mild topical steroid and which ones have antimicrobial properties?

Answer 6

Mild - hydrocortisone 1-2.5%

Anti-microbial - Canesten HC, Daktocort, Fucidin H

Question 7

What is a moderate topical steroid and which one has antimicrobial properties?

Answer 7

Eumovate, Betnovate-RD

With antimicrobial - Trimovate

Question 8

What is a potent topical steroid and which ones has antimicrobials/ salicylic acid?

Answer 8

Betnovate, Elocon
With antimicrobials - Betnovate-C, Fusibet
with salicylic acid - Diprosalic

Question 9

What is a very potent steroid?

Answer 9

Dermovate

Question 10

How should you tell a patient to apply their topical steroid?

Answer 10

No more than twice daily, once daily usually sufficient
Spread thinly
Apply about 20-30 mins after any emollient has been supplied

Question 11

What are the adverse effects of steroids?

Answer 11

Mild and moderately potent steroids are associated with few side effects and are safe to use on children and thin skin of face and flexures.
Local SE: spread and worsening of untreated skin conditions, thinning of the skin, irreversible striae and telangeictasia, acne or worsening of acne or rosacea, hypopigmentation

Question 12

What are topical calcineurin inhibitors e.g. tacrolimus used for?

Answer 12

Moderate to severe atopic eczema

Facial psoriasis

Question 13

When would you use non-sdedating and sedating oral antihistamines?

Answer 13

Non-sedating: chronic urticaria e.g. fexofenadine and cetirizine
Sedating - for itching e.g. hydrozyzine, chlorphenamine, and treating underlying skin problem or systemic disease that is causing the itch

Question 14

What are some examples of topical antifungals?

Answer 14

Imidazole antifungals e.g. clotrimazole, econazole, miconazole
Terbinafine cream - more effective but more expensive

Question 15

When would you use topical antifungals?

Answer 15

localised infection: tinea corporis, tinea cruris, tinea manuum, tinea pedis

Question 16

What instructions would you give a patient for whom you had prescribed topical antifungals?

Answer 16

Apply twice a day. To prevent relapse continue local antifungal for 1-2 weeks after the disappearance of all signs of infection.

Question 17

When would you use systemic antifungals?

Answer 17

Infections of scalp (tinea capitis) or nail (tinea unguium) or if fungal infection is widespread, disseminated or intractable.
Options: terbinafine, azoles or griseofulvin.

Question 18

What is pityriasis versicolor and how would you treat it?

Answer 18

Yeast infection
Use ketoconazole shampoo as a body wash plus topical imidazole antifungals.
If infection is widespread, treat systemically e.g. with itraconazole.

Question 19

How would you treat candidiasis?

Answer 19

Topical imidazole antifungal e.g. clotrimazole or miconazole

Question 20

How would you treat scabies?

Answer 20

5% permethrin cream over whole body and wash off after 8-12 hours. Repeat application after 7 days.
All members of the affected household/sexual contacts or other close contacts should be treated simultaneously, including those who are not itching.
The itch and inflammation can be treated with sedating antihistamine, emollient and topical corticosteroid.

Question 21

When would you use topical vit D analogues e.g. calcipotriol?

Answer 21

Dovobet ointment - calcipotriol combined with betnovate. Indication: localised psoriasis.
Apply once or twice daily. Not suitable for widespread disease. Can cause local skin reactions e.g. itching, erythema, burning, parasthesia, dermatitis, but reduced if combined with a topical corticosteroid.
Avoid in disorders of calcium metabolism.

Question 22

When would you use coal tar preparations?

Answer 22

Chronic plaque psoriasis.

Question 23

What can you use to treat scaly scalps - psriasis, eczema, seb derm?

Answer 23

Cocois scalp ointment - coal tar solution and salicylic acid in coconut oil with applicator nozzle.
Apply to scalp once weekly and leave on overnight. Shampoo off the next morning.

Question 24

What are the possible treatments for acne?

Answer 24

Mild - benzoyl peroxide, topical antibacterials e.g. erythromycin and clindamycin, adapalene for comedonal acne, oral antibiotics e.g. tetracycline, lymecycline, erythromycin
If these fail - COCP especially Dianette 
Oral retinoids (only prescribed by or under the supervision of consultant dermatologist) - isotretinoin

Question 25

What should you discuss with a patient before giving them isotretinoin?

Answer 25

Dryness of the skin and mucous membranes, nose bleeds and joint pains.
The drug is teratogenic and must not be given to women of child-bearing age unless they practice effective contraception.
Reports of depression and suicide. A causal link has not been established but discuss the possibility with the patient before initiating treatment.
Monitor liver function and blood lipids

Question 26

When is methotrexate prescribed for psoriasis?

Answer 26

When not controlled by topical tx.
Other indications: psoriatic arthritis, RA, Crohn’s.
Prescribe with folic acid to reduce adverse effects.

Question 27

What are the adverse effects of MTX?

Answer 27

Anorexia, nausea
Low WBC - patient should be advised to report all symptoms and signs of infection, esp sore throat
Hepatitis, liver fibrosis, rarely cirrhosis
Interstitial pulmonary fibrosis (seen in RA)
Teratogenic - men and women should avoid conception for at least 3 months after stopping

Question 28

What monitoring should be done when a patient is on MTX?

Answer 28

FBC, U&E and LFTs before starting treatment, then repeat weekly until therapy stabilised, thereafter monthly.

Question 29

When is ciclosporin used? What are potential side effects.

Answer 29

Severe atopic dermatitis and severe psoriasis.
SE - nephrotoxic. Long term use increases risk of skin cancer particularly in patients who have had previous phototherapy.