4. Dermatology A

Question 1

Main function of skin

Answer 1

• Barrier and protection - epidermis
• Strength and flexibility - dermis
• Fat and insulation - SC tissue

Question 2

What is found in epidermis?

Answer 2

Stratum corneum is outside layer which is thickest on palms and soles of feet

Langerhan cells are found here - immune function

Question 3

What is found in the dermis?

Answer 3

• Made of collagen, elastin and fibrillin
• Nerves
• Glands
• Hair follicles
• Blood vessels

Question 4

Outline psoriasis from epidermis

Answer 4

Increased cell turnover
Hyperproliferation/thickening of epidermis
Causes scaly plaques
Dilation of BV causes erythema

Question 5

What diseases affects flexural areas?

Answer 5

Eczema

Question 6

What can affect mucus membranes?

Answer 6

Lichen planus with lace-like reticular pattern

Question 7

What is the first line treatment for mild/moderate acne?

Answer 7

Topical benzoyl peroxide + topical adapalene
Topical benzoyl peroxide + topical clindamycin
Topical tretinoin + topical clindamycin

Question 8

What is the treatment for moderate/severe acne?

Answer 8

Either of first 2 options from mild/moderate OR

Topical adapalene + topical benzoyl peroxide + oral doxycycline/oral lymecycline
Topical azelaic acid + oral doxycycline/oral lymecycline

Can use COCP instead of oral abx
Isotretinoin is reserved for secondary care

Question 9

What is SCC?

Answer 9

• Common variant skin cancer
• Arises from squamous cells -flat, thin cells found in dermis
• Rapidly expanding, ulcerated nodules
• Some bleed

Question 10

What are the risk factors of developing a squamous cell carcinoma?

Answer 10

Sun exposure
Tanning beds
Immunosupression
Genetic conditions eg Xeroderma pigmentosum

Question 11

How is SCC managed?

Answer 11

• Surgical excision with 4mm margin (6mm in high risk lesions)
• Mohs micrographic surgery - tissue removed and examined under microscope in real time to ensure all cancerous cells are removed
• Radiotherapy
• Curretage and cautery
• Topical 5-fluorouracil or imiquimod
• Cryotherapy

Question 12

When is cryotherapy used for a SCC?

Answer 12

If there is a low risk of it being cancerous e.g. flat and superficial

Question 13

Safety netting for SCC

Answer 13

• If increasing in size rapidly and invading surrounding structures
• Lumps in neck

Question 14

What is BCC?

Answer 14

• Most common type of non-melanoma skin cancer worldwide
• Exposure to UV light
• More risk if fairer and easily burn
• Can vary greatly in appearance
• Curable in most cases
• Rarely spread

Question 15

Management for BCC?

Answer 15

• Wide local excision
• Cryotherapy
• Iquimoid cream
• Curretage
• Mohs micrographic surgery
• Radiotherapy

Question 16

Safety netting for BCC

Answer 16

• 50% of people will develop 2nd BCC within 3yrs of first
• Prevent further lesions by preventing sunburn
• At increased risk of other cancers eg melanomas
• Do regular self skin checks and annual skin checks
• Look for change in shape, colour, size 7mm or more, irregular

Question 17

How does measles present?

Answer 17

• Intial cough and fever - URTI symptoms then rash
• Rash starts behind ears and on face
• VERY infectious
• Check for Koplik spots in buccal mucosa
• Only affects unvaccinated usually

Question 18

What does a measles rash look like?

Answer 18

Erythematous maculopapular rash, non pruiritic

Question 19

Where to refer for suspected melanoma?

Answer 19

2 week wait for pigmented lesion clinic

Question 20

How does ringworm appear?

Answer 20

Round
Central clearing

Question 21

What is the treatment for ringworm?

Answer 21

• Topical clotrimazole or miconazole if isolated OTC
• Topical hydrocrotisone 1% if lots of inflammation
• Oral terbinafine if extensive

Question 22

How long do fungal infections take to resolve?

Answer 22

• Skin 3-4 weeks
• Nails can take 6 weeks-6 months of treatment

Question 23

What can be a cause of recurrent thrush?

Answer 23

Lichen sclerosis

Question 24

Skin conditions that cause pruritis?

Answer 24

Scabies
Uraemia
Lichen planus
Lichen sclersosis
Nodular prurigo
Eczema
Bites

Question 25

What is Pompholyx?

Answer 25

Eczema and blisters

Question 26

Pityriasis rosea vs versicolour

Answer 26

Versicolour is fungal infection
Need antifungals
Rosea is just self limiting

Question 27

Lymes disease - presentation and treatment

Answer 27

Target lesion
After walking in long grass that deer are found - tick bite
3 weeks of Doxycycline

Question 28

Nappy rash vs candida

Answer 28

• Nappy rash commonly caused by ammonia in urine irritating skin
• Spared skin sections which do not touch ruine
• Fluffier edges compared to candida

Question 29

What is psoriasis which is just back droplets and not plaques?

Answer 29

Guttate psoriasis - 1/3 have no FH and do not go on to develop plaques

Question 30

How is psoriasis managed?

Answer 30

PSORIASIS

Phototherapy
Salicylic acid
Ointments (emolients)
Retinoid (oral acitretin)
Calcineurin Inhibitors
Vitamin A
Steroids
Immunosupressors e.g. methotrexate
Sun (vitamin D analogues)

Question 31

What scoring is used for psoriasis?

Answer 31

PEST score

Question 32

What does psoriasis often come along with?

Answer 32

Dactilytis- sausage finger
Achilles tendonitis
Plantar fasciitis

Question 33

List steroids in order of potency

Answer 33

1. Hydrocortisone
2. Eumovate or Betnovate RD- clobetasone butyrate or reduced dose betamethasone valerate 0.025%
3. Betnovate -betamethasone valerate 0.1%
4. Dermovate - clobetasol propionate 0.05%