Dermatology

Question 1

What is the classical distribution of flea bite marks?

Answer 1

Below the knees typically, if animals sleep on the bed then can be higher up

Question 2

How do bed bug bites appear?

Answer 2

Pruritic maculopapular lesions with haemorrhagic punctums

Question 3

A patient who has just come back from a walking holiday presents with a bulls-eye rash.

What is the technical term for this, and what does it indicate?

Answer 3

Erythema migrans

Tick bite causing Lyme disease

Question 4

What is the cause of itching with lice?

Answer 4

Agents in louse salivary antigens cause itching

Question 5

What are the 4 main effects of local corticosteroids?

Answer 5

1. Anti-inflammatory
2. Immunosuppressive
3. Anti-proliferative
4. Vasoconstriction

Question 6

If a flare of a skin issue is controlled by topical steroids, how should the treatment be ceased?

Answer 6

Taper the treatment with less potent steroid once flare-up is under control

Question 7

What strength of steroid cream should be used on thin or flexural skin e.g. face/groin/scrotum?

Answer 7

Mild or moderately potent steroids

Question 8

How long should an initial course of topical steroids be prescribed for?

Answer 8

Usually if symptoms do not improve after 3-7 days the condition needs reassessment

Question 9

How many potencies do topical steroid preparations come in?

Answer 9

4 - mild, moderate, potent, and very potent

Question 10

What are the mild topical steroids?

Answer 10

Hydrocortisone 0.1%, 0.5%, 1.0% and 2.5%

Question 11

What is the issue with hydrocortisone 2.5%?

Answer 11

It costs waaaaaaay more than other topical steroids of any other potency

Question 12

What are the brand names of mild topical corticosteroids?

Answer 12

Dioderm
Mildison
Synalar 1 in 10

Question 13

What are the commonly used moderate potency topical steroids?

Answer 13

Betnovate RD, Eumovate

Question 14

What are the commonly used potent steroids?

Answer 14

Generic belcometasone dipropionate 0.025%
Diprosone, Betnovate

Question 15

What are the very potent topical steroids that are used frequently?

Answer 15

Dermovate
Clarelux
Nerisone forte

Question 16

How should topical steroids be applied?

Answer 16

-Thin layer
-Once or twice per day
-1 fingertip unit for area the size of two flat hand-prints

Question 17

What volume of steroid cream should be provided for a 2 week course to cover either face and neck, both hands, genital region, or the scalp?

Answer 17

15-30g

Question 18

What volume of steroid cream should be provided for a 2 week course to cover both arms?

Answer 18

30-60g

Question 19

What volume of steroid cream should be provided for a 2 week course to cover both legs, or trunk?

Answer 19

100g

Question 20

When applying emollient alongside topical steroids, how long should be left between applications?

Answer 20

20-30 minutes

Question 21

Can pregnant women use topical steroids?

Answer 21

Yes - safest at lowest potencies and on small areas

Question 22

Can breastfeeding women use topical steroids?

Answer 22

Yes - remove from any breast area with warm water prior to feeding and reapply after feeding

Creams are preferred as they are easier to remove than ointments

Question 23

What side effects can occur from topical application of steroids?

Answer 23

-Acne vulgaris
-Folliculitis
-Skin atrophy
-Telangiectasia
-Burning/stinging
-Striae
-Contact dermatitis
-Skin depigmentation
-Excessive hair growth

Question 24

How common are systemic adverse effects of topical steroids?

Answer 24

Rare - more likely if using potent steroid over large area for prolonged period of time

Question 25

If systemic adverse effects were to occur secondary to topical steroid use, what are the main side effects that could be noted?

Answer 25

-Adrenal suppression
-Cushing’s syndrome
-Growth Suppression
-Visual disturbance

Question 26

What additional element may increase risk of adverse systemic reactions when giving potent/very potent topical steroids?

Answer 26

Using an occlusive dressing in same area

Question 27

How can a topical steroid used for maintenance therapy be used to minimise risk of adverse reactions?

Answer 27

Using intermittently with time periods where emollients are used on their own in between

Question 28

How should topical steroids be applied to skin?

Answer 28

Rubbed gently in, in direction of hair growth

Question 29

What risk is there when using topical steroids if a patient is a smoker?

Answer 29

Topical steroids can be flammable, and if contact dressings/clothing can make them easily flammable also