Rash disease profiles

Question 1

What is the cause of psoriasis

Answer 1

Unknown

Question 2

What is the pathological process of psoriasis?

Answer 2

Increased epidermal turnover

Question 3

What is the Koebner phenomenon?

Answer 3

Production of new lesions at sites of trauma

Question 4

How is psoriasis described?

Answer 4

Well demarcated, silvery plaques with erythema underneath (due to blood vessels being closer to the surface)

Question 5

What is the most common type of psoriasis?

Answer 5

Chronic plaque psoriasis // psoriasis vulgaris

Question 6

Which sites of psoriasis most commonly found on?

Answer 6

Extensor surfaces

Question 7

What other systemic effects can psoriasis have?

Answer 7

Nail changes and joint pain

Question 8

How is psoriasis diagnosed?

Answer 8

Clinically based upon appearance and location

Question 9

What is the main stay of psoriasis management?

Answer 9

Emollients

Question 10

What type of psoriasis affects the whole body?

Answer 10

Guttate psoriasis

Question 11

What is the clinical presentation of lichenoid disorders?

Answer 11

Very itchy papules

Question 12

Where do lichenoid disorders typically affect?

Answer 12

Wrists/forearms + shins/ankles, often has mucosal symptoms

Question 13

What is sign on histology of lichenoid disorders?

Answer 13

Saw tooth pattern (notching) of the dermis into the epidermis, thickened epidermis

Question 14

How are lichenoid disorders diagnosed?

Answer 14

Clinical diagnosis with confirmation on histology

Question 15

How are lichenoid disorders treated?

Answer 15

Self limiting (12-18 months)
Give potent or very potent steroids
If widespread, oral steroids

Question 16

What is the cause of pemphigus and pemphigoid conditions?

Answer 16

Autoimmune blistering conditions

Question 17

What is the difference between the bull produced in pemphigus and pemphigoid?

Answer 17

Pemphigus = think and flaccid
Pemphigoid = large and tense

Question 18

Which layer of the skin is affected in pemphigus vs pemphigoid?

Answer 18

Pemphigus: epidermal cell adhesion (superficial)
Pemphigoid: sub-epidermal (deep)

Question 19

What is acantholysis and which immunobullous disorder exhibits this?

Answer 19

Lysis of intercellular adhesion sites

Pemphigous

Question 20

How are immunobullous disorders diagnosed?

Answer 20

Skin biopsy with immunofluorescence for autoantibodies

Question 21

How are immunobullous disorders treated or managed?

Answer 21

Management: emollients/topical steroids
Treatment: systemic steroids/immunosuppressive agents
Self limiting in months - years

Question 22

What is the pathophysiology of acne?

Answer 22

Increased androgen during puberty
Increased sebum and keratin production
Plugs polo-sebaceous unit
Bacterial infection

Question 23

How is acne managed/treated?

Answer 23

Avoid oily substances or other triggers
Topical: retinoids (dry out skin), antibiotics (antibacterial + anti-inflammatory effects)
Oral: antibiotics + isotretin (oral retinoid)

Question 24

What is the clinical presentation of rosacea?

Answer 24

Erythema across cheeks and forehead, pustules, thickened skin, enlarged nose
Aggravated/stimulated by sunlight, spicy foods, stress, alcohol

Question 25

How is rosacea treated/managed?

Answer 25

Topical metronidazole

If severe; oral tetracycline or low dose isotretin

Question 26

Which disease is dermatitis herpetiformis associated with?

Answer 26

Coeliac

Question 27

How to eczema present?

Answer 27

Itchy, erythematous, ill-defined scaly lesions

Question 28

What pathological changes are seen in eczema?

Answer 28

Spongiosis with inflammatory infiltrates

Question 29

What is the difference between contact allergic dermatitis and irritant dermatitis?

Answer 29

Contact allergic dermatitis: specific immune response to an allergen
Irritant dermatitis: non-specific immune response to a repeated stimulus from an irritant

Question 30

What is the main stay of eczema treatment?

Answer 30

Emollients

Question 31

What is eczema herpeticum and what is the typical presentation?

Answer 31

Herpes simplex virus infection, presents as monomorphic punched out lesions

Question 32

What causes stasis eczema?

Answer 32

Increased hydrostatic pressure in the legs