Dermatology

Question 1

How do you describe lesions?

Answer 1

Flat = macule or patch

Fluid-filled = vesicle <0.5cm, pustule or bulla >0.5cm

Raised = papule <0.5cm or nodule >0.5cm

Question 2

RFs for SqCC

Answer 2

UV light, FHx, ligher skin and acitinic keratosis

Question 3

Describe SqCC lesion and invasion?

Answer 3

Lesion = hyperkeratotoic, scaly, crusty, ulcerated, non-healing and rolled edges.

Inasion = local dermis and can metastasise to LLBB lungs liver bone brain

Question 4

BCC RFs?

Answer 4

UV light, Fhx and ligher skin

Question 5

BCC lesion and invasion?

Answer 5

Lesion = nodule, pearly edges, rolled edges, central ulcer (rodent ulcer) and central fine telangiectasia

Invasion = slow growing, local invasion and does not typically metastasise

Question 6

4 subtypes of BCC?

Answer 6

Nodular = most common

Superficial = flat shape

Morpheic = yellow waxyplaque, scar like

Pigmented = dense colour, specks of colour ?melanoma

Question 7

Melanoma RFs?

Answer 7

UV light, Fhx and lighter skin

Question 8

Melanoma lesion and invasion description?

Answer 8

ABCDE
Asymmetry
Border (irregular)
Colour (pigmented)
Diameter
Evolution (size/shape)

Local inasion and can metastasise LLBB

Question 9

What are the subtypes of malignant melanoma?

Answer 9

Superficial spreading = most common

Nodular = domed shape and rapid growth

Lentigo maligna = flat lesions on face and elderly

Acral lentiginous = pals, soles and nail beds in non-caucasians

Question 10

Ix for cancerous lesions?

Answer 10

Melanoma and SqCC = 2WWR. BCC = 6WW

Physical exam and obvs. Dermatoscope.

Bloods = calcium and ALP for bone mets and LFT for liver.

Imaging of CT for staging

Biopsy = breslow thickness for melanoma invasion

Question 11

What are melanocytic naevi and description?

Answer 11

Benign neoplasm of the melanocytes in eidermis

Often congenital and arise during childhood

Symetrical, flat, regular borders.

Not ABCDS

Question 12

Eczema risk factors and triggers?

Answer 12

PMHx or FHx of atopy e.g. food allergy, hayfever and asthma.
Filaggrin gene mutation.

Triggers = soaps, shampoos, food allergies, pollen, ouse dust ,mite and pets

Question 13

Describe eczema lesion?

Answer 13

Dry skin, itchy, erythermatous, distribution on flexures and lichenification if chronic

Question 14

What are the subtypes of eczema?

Answer 14

Atopic dermatitis = Type 1 and 4 sensitivity (Ig-E mediated). on the flexures

Contact dermatitis = Type 4 hypersensitivity. Often nickel or latex. Two types: irritant and allergic

Discoid dermatitis = middle aged/elderly and coin-shaped plaques

Question 15

Other Eczema types?

Answer 15

Seborrhoeic dermatitis = yellow, greasy, scaly rash. Distribution eyebrows, nasolabial and scalp (cradle cap)

Dyshidrotic (pompholyx) = itchy painful blisters and on palms and plantars

Eczema herpeticum = superimposed HSV-1`

Question 16

Psoriasis RFs and triggers?

Answer 16

Hyperproliferation of keratinocytes.

PMHx and FHx or psoriasis.

Triggers = stress alcohol and smoking

Question 17

Describe psoriasis lesion and nail signs?

Answer 17

Purple, silvery plaques. Dry, flaky skin. Itchy and painful and distributed on extensors and scalp

Nail signs = oncholysis, pitting and subungual hyperkeratosis.

Psoriatitc athritis = symetrical polyarthritis

Question 18

Oncholysis DDx?

Answer 18

Psoriasis, fungal infection, trauma and thyrotoxicosis

Question 19

Psoriasis subtypes?

Answer 19

Plaque = most common and previous description

Guttate = raindrop plaques (often 2 weeks post strep

Flexural = body folds e.g. axilla, groin

Pustular AKA palmo-plantar and where it says

Erythrodermic = systemic body redness and inflammation with temp dysregulation, electrolyte imbalances and requires hospitalisation

Question 20

Inflammatory Ix?

Answer 20

Physical ecam and basic obvs

Bedside tests like skin patch testing for contact dermatitis and IgE RAST bloods for atopic dermatitis

Skin prick testing for food allergies

Question 21

Describe similarities of cellulitis and erysipelas?

Answer 21

Acute onsent and inflammed.

RFs = wounds, ulcers, bites, IV cannula and immunosuppresion

Question 22

Cellulitis Specifics?

Answer 22

Dermis and subcut tissue. More patchy borders, less common systemic and more common for sepsis

Question 23

Erysipelas specifics?

Answer 23

Epidermis , well demarcated, systemic fevers and rigors and uncommon cause of sepsis

Question 24

Complications of cellulitis?

Answer 24

Abscess, sepsis, necrotising fasciitis

periorbital cullulitis and orbital cellulitis

Question 25

Ix for cellulitis and erysipleas?

Answer 25

Physcial exam and obvs
Skin swab MCS
Bloods for high WCC, CRP and blood culture and swab show strep pyogenes or staph aureus

Imaging of CT/MRI for orbital cellulitis

Question 26

Management of cellulitis/erysipelas?

Answer 26

Conservative = draw around, oral fluids, analgesics and monitor obvs

Medical = oral Abx (flucloxacillin and if severe of eye co-amoxiclav

Admit if septic or confused

Question 27

Describe erytherma nodosum?

Answer 27

Bilateral nodules, tender, red or purple and on anterior shins or knees.
Do not ulcerate or scar

Question 28

Causes of erytherma nodosum?

Answer 28

Infections = s.pyogenes, TB and HIV
Systemic = IBD and sarcoidosis and Behcets
Drugs = sulphonamides
Pregnancy

Question 29

Describe molluscm contagiosum?

Answer 29

Skin infection due to molluscum contagiosum virus causing smooth papule and umbilicated. usually painless and often itch

Question 30

RFs and transmission of molluscum contagiosum?

Answer 30

Immunocompromised e.g. HIV and close contact e.g. sex and swimming pools

Question 31

Description of erytherma multiforme?

Answer 31

Target lesions = central vesicle and crust, ring of pallor and ring of erytherma

Distributed on hands and then spread

Question 32

Symptoms and causes of erytherma multiforme?

Answer 32

Prodome (fever and aches) and tender/itchy and pain

Causes = infections (HERPES, Mycoplasma and HIV)
Drug reation e.g. sulphonamides

Question 33

Ix for erytherma nodosum, multiforme and molluscum contagiosum?

Answer 33

Physical exam and basic obvs.

Maybe HIV and underlying cause diagnosi