Immunology 5: Inflammatory dematoses

Question 1

What is the role of melanin in the skin?

Answer 1

Protect keratinocyte nuclei from damage

Question 2

Recall the life cycle of a keratinocyte

Answer 2

Originates in BM
Migrates supradermally, producing keratin
Dead and anucleated by the time they reach stratum corneum
Form “bricks” in barrier of skin (“cement” = lipids)

Question 3

Recall the general pathophysiology of eczema

Answer 3

Defect in barrier function of skin

Question 4

Recall the types of sweat gland, and the type of secretion they produce

Answer 4

Eccrine - watery

Apocrine - viscous

Question 5

What are the 2 main components of the matrix in the dermis?

Answer 5

Collagens

GAGs

Question 6

Which part of the skin is affected by acne?

Answer 6

Pilosebaceous unit

Question 7

Summarise the pathogensis of acne

Answer 7

1. Androgenic stimulation
2. Sebaceous gland hypertrophy
3. Accumulation of sebum and keratin

Question 8

What are black and white heads and what is the proper term given to them?

Answer 8

Black head = buildup of sebum + keratin at the infundibulum = open comedone
White head = black head with skin on top = closed comedone

Question 9

What are the main areas affected by acne?

Answer 9

Face
Neck
Upper back
Upper chest

Question 10

By what other name is eczema known?

Answer 10

Dermatitis

Question 11

Which of the common skin conditions are classed as atopic?

Answer 11

Eczema

Acne

Question 12

Recall how eczema tends to affect individuals over their lifetime

Answer 12

Tends to start young and go away by adulthood

Fist step in atopic march

Question 13

Why doe seczema predispose to other atopic diseases?

Answer 13

Defective barrier function of the skin allows infiltration of other allergens

Question 14

Recall 3 things that may enter the body through the skin due to eczema

Answer 14

Allergens
Irritants
Pathogens

Question 15

What is the main pathogen involved in skin infection?

Answer 15

Staphylococcus aureus

Question 16

What is the function of the filagrin protein?

Answer 16

Epidermal protein

Maintains barrier function

Question 17

What is palmar hyperlinearity a sign of?

Answer 17

Filagrin mutation

Question 18

What are the worst-affected areas by eczema on a baby?

Answer 18

Cheeks
Elbows
Knees

Question 19

What are the worst-affected areas by eczema in adults?

Answer 19

Where there is sweat - eg antecubital fossa

Question 20

Recall 4 types of eczema

Answer 20

Eczema herpeticum
Seborrheic
Allergic-contact dematitis
Discoid

Question 21

What type of skin disease is dandruff?

Answer 21

Mild seborrheic eczema

Question 22

Recall the pathogenesis of eczema herpeticum

Answer 22

HSV able to penetrate skin due to defective barrier

Question 23

Recall which areas are most commonly affected in severe seborrheic eczema

Answer 23

Nasolabial folds
eyebrows
forehead

Question 24

Recall the pathogenesis of seborrheic eczema

Answer 24

Overgrowth of naturally-occurring yeast on skin and a secondary dermatitis reaction to this

Question 25

Recall 2 common allergens that can cause ACD

Answer 25

Makeup | PPD in black henna

Question 26

Where is the most common site affected by discoid eczema?

Answer 26

Legs

Question 27

What is the main treatment for discoid eczema?

Answer 27

Emoliant

Question 28

What is the primary form of inflammatory dermatosis?

Answer 28

Psoriasis

Question 29

Recall 4 types of psoriasis

Answer 29

Chronic plaque Guttate Palmoplantar pustulosis Generalised pustular psoriasis

Question 30

Recall a common comorbidity that presents with psoriasis

Answer 30

Psoriatic arthritis

Question 31

Describe the appearance of psoriasis

Answer 31

Salmon-pink coloured plaques

Question 32

What triggers are required to cause psoriasis?

Answer 32

``` Multigenic - but requires genetic susceptibility Environmental trigger (infection, stress, drugs) ```

Question 33

Recall the 6 steps of the pathogenesis of psoriasis

Answer 33

1. T cell infiltration of dermis 2. Cytokine and TNF-a release 3. Acanthosis 4. Hyperkeratosis 5. Parakeratosis 6. Local vasodilation

Question 34

Describe the distribution of psoriasis over the body

Answer 34

Very symmetrical | ofetn affects scalp, face, elbows, groin, axilla

Question 35

What nail signs are produced by psoriasis?

Answer 35

Oncolysis | Subungual hyprkeratosis

Question 36

Describe the appearance of guttate psoriasis

Answer 36

Like little raindrops

Question 37

Which group is most susceptible to guttate psoriasis?

Answer 37

Young people

Question 38

What is the cause of guttate psoriasis?

Answer 38

Strepococcus sore throat

Question 39

What is the treatment for guttate psoriasis?

Answer 39

Antibiotics | Topical steroids

Question 40

Which form s psoriasis is driven by genetics alone?

Answer 40

Palmoplantar pustulosis

Question 41

Which form of psoriasis will require emergency hospital admission?

Answer 41

Generalised pustular psoriasis

Question 42

What is bulbous pemphigoid?

Answer 42

Autoimmune blistering condition

Question 43

What are the auto-antibodies directed against in bullous pemphigoid?

Answer 43

BP180 and BP230 - proteins that bind dermis to epidermis

Question 44

Why does bullous pemphigoid have a high mortality rate?

Answer 44

Blisters easily become septic

Question 45

Which group is most susceptible to bullous pemphigoid?

Answer 45

Elderly

Question 46

Other than bullous pemphigoid, recall a condition that results from basement membrane breakdown

Answer 46

Epidermolysis bullosa

Question 47

What is pemphigus vulgaris?

Answer 47

Autopimmune superficial blistering condition

Question 48

Recall the 2 most common autoimmune skin conditions and how they can be differentiated

Answer 48

``` Bullous pemphigoid (deep) Pemphigus vulgaris (superficial) ```

Question 49

Recall the appearance of pemphigus vulgaris

Answer 49

Superficial blisters that easily break to produce erosions and crusted lesions

Question 50

In pemphigus vulgaris, what is the auto-Ab directed against?

Answer 50

Desmoglein | = Component of epidermal hemidesmosome

Question 51

What is the result of auto-Ab binding to desmoglen in PV?

Answer 51

Loss of cell-cell ahesion (ancatholysis)