Inflammatory Skin Disease

Question 1

What is the difference between eczema and dermatitis?

Answer 1

Nothing, they are interchangeable

- mean inflammation of the skin

Question 2

What is the aetiology of eczema?

Answer 2

Combination of genetic, immune and reactivity to a variety of sitmuli

Question 3

How can inflammation in eczema be due to inherited abnormalities?

Answer 3

Due to a barrier defect
- causes increased permeability and reduced anti-microbial function
Abnormality in filaggrin expression (filament-associated protein which bind to keratin fibres in the epidermal cells)
- gene found on chromosome 1

Question 4

Name the different classification/types of eczema

Answer 4

Endogenous
- atopic, seborrhoeic, dicoid, varicose and pmpholyx
Exogenous
- contact (allergic, irritant) and photorection (allergic, drug)

Question 5

What is atopic eczema and its associations?

Answer 5

Itchy inflammatory skin condition with high Ig-E immunoglobulin antibody levels
Has genetic and immune aetiology
Associated with asthma, allergic rhinitis, conjunctivitis and hayfever

Question 6

Where is atopic eczema found on babies?

Answer 6

Most prominent on the face

Flexor sites

Question 7

How common is atopic eczema?

Answer 7

10-15% of infants are affected (remission occurs in 75% by the age of 15)

Question 8

Is atopic eczema inherited?

Answer 8

2/3rds of people with eczema have a family history of atopy

Question 9

Describe the appearance of the skin in atopic eczema.

Answer 9

Symmetrical background redness
Broken skin
Small areas of ulceration
Itchy
Occasionally vesicular
Thickened skin
Poorly defined

Question 10

Why is infection of atpoic eczema more common in infants?

Answer 10

Babies are dirty and they drool a lot, introducing bacteria through the interrupted skin barrier

Question 11

Can infant atopic eczema be caused by food?

Answer 11

Yes but it is more common for the existing eczema to be exacerbated by food (o.e. milk)

Question 12

What are the complications of atopic eczema?

Answer 12

Bacterial infection - S.Aureus
Viral - molluscum, viral warts, eczema herpeticum (tends to be sore)
Tiredness (up all night scratching)
Growth reduction 
Psychological impact

Question 13

How is atopic eczema managed?

Answer 13

Emollients - endogenous oils 
Topical steriods - helps with itching and burning
Bandages - hold topical preparations in place and stop babies scratching 
Antihistamines 
Antibiotics/anti-virals
Education for parents and child
Avoidance of exacerbating factor (dust)
National Eczema Society

Question 14

What type of hypersensitivity reaction is contact dermatitis?

Answer 14

Type 4 - delayed T-cell

Question 15

What causes contact dermatitis?

Answer 15

Precipitated by an exogenous agent

• irritant (direct noxious effect on skin barrier)
• allergic - type IV hypersensitivity reaction

Question 16

What are the common allergens involved in contact dermatitis?

Answer 16

Nickel (jewellery, zips, scissors, coins)
Chromate (cement, tanned leather)
Cobalt (Pigments/dyes)
Colophony (glue, adhesive tape, plasters)
Fragrance (cosmetics, creams and soaps)

Question 17

Describe seborrhoeic dermatitis and its cause.

Answer 17

Chronic, scaly inflammation
Face, scalp and eyebrows - often confused with dandruff or facial psoriasis
Caused by overgrowth of Pityrosporum ovale yeast

Question 18

Which group of people does seborrhoeic dermatitis affect the worst?

Answer 18

Teenagers, due to their sebaceous/oily skin

Question 19

What kind of inflammatory skin disease is a presenting feature of severe HIV?

Answer 19

Seborrhoeic dermatitis

Question 20

What are the management options for seborrhoeic dermatitis?

Answer 20

Scalp
- medicated anti-yeast shampoo (i.e. antifungal ketoconazole)
Face - anti-microbial, mild steroids (Daktacort cream) and a simple moisturiser

Question 21

What causes venous dermatitis?

Answer 21

Underlying venous disease, affecting the lower legs
- incompetence of the deep perforating veins
- increased hydrostatic pressure
Therefore more common in the elderly population

Question 22

Describe the appearance of venous dermatitis.

Answer 22

Dry
Itchy
Ulceration when scratched
Hyperpigmentation

Question 23

How is venous dermatitis treated?

Answer 23

Emollient - exogenous oils
Mild/moderate topical steroid
Compression bandaging/stockings
Consider venous surgical intervention - varicose vein treatment

Question 24

List the four most common types of eczema.

Answer 24

Atopic eczema, contact dermatitis, seborrhoeic dermatitis and varicose eczema.

Question 25

What is the definition psoriasis?

Answer 25

A chronic relapsing and remitting scaling skin disease which may appear at any age and affect any part of the skin

Question 26

Describe the pathophysiology of psoriasis.

Answer 26

T-cell mediated autoimmune disease Abnormal infiltration of T-cells - release of inflammatory cytokines including interferon, interluekins and TNF - increases keretinocyte proliferation

Question 27

What other medical conditions is psoriasis linked to?

Answer 27

Psoriatic arthritis Metabolic syndrome Liver disease/alcohol misuse Depression

Question 28

Describe the genetic component of psoriasis.

Answer 28

One sibling with psoriasis - 24% risk One parent with psoriasis - 28% risk One sibling and one parent with psoriasis - 41% risk Two parents with psoriasis - 65% risk Both parents and a sibling - 83% risk PSORS genes and HLA-Cw0602 types associated in certain subtypes

Question 29

Name the different types of psoriasis.

Answer 29

Plaque - textbook Guttate - raindrop Pustular Erythrodermic - red skin Koebner phenomenon - scratching of skin causes psoriasis Palmar/plantar pustules - pustules on just hands and feet

Question 30

Describe the skin in plaque type psoriasis.

Answer 30

``` Raised Larger than 1cm White scale on surface (hyperkeratinosis) Symmetrical Well defined Scaly Dry - no moisture ```

Question 31

What are some of the common locations for plaque psoriasis?

Answer 31

``` Scalp (including behind and in the ears) Eyelids Mouth Lips Skin folds Hands Feet Nails ```

Question 32

Describe some common nail changes in plaque psoriasis.

Answer 32

Nail pitting Onycholysis - nail lifting off the nail bed Skin may be affected around it Hyperkeratosis

Question 33

Describe the skin changes seen in pustular psoriasis.

Answer 33

White pustules - blisters of noninfectious pus Red skin Different to chronic plaque psoriasis

Question 34

Describe the skin changes seen in erythrodermic psoriasis.

Answer 34

``` The whole skin is red and hot Fine scale Flaky Pain and itching (systemically unwell) ```

Question 35

How is psoriasis managed?

Answer 35

``` Scoring system - DLQI, PASI or PEST Topical creams and ointments Phototherapy light therapy Acitretin Methotrexate Ciclosporin Biological therapies - infliximab, etanercept and adalumimab ```

Question 36

How many people with psoriasis develop psoriatic arthritis?

Answer 36

20%

Question 37

What topical therapies are used in psoriasis treatment?

Answer 37

Moisturisers - help reduce dryness, flaking Steriods - reduce autoimmune response, redness, itching and inflammation Slow down keratinocyte proliferation - vitamin D analogues - coal tar - topical retinoids (vitamin A) i.e. Tazarotene

Question 38

Describe ultraviolet phototherapy in psoriasis treatment.

Answer 38

``` Non-specific immunosuppressant therapy Can reduce T-cell proliferation Encourages Vitamin D (reduces skin turnover) UV-B light most commonly used UV-A with psoralen photosensitiser ```

Question 39

What are the risks of UV phototheapy?

Answer 39

Short term - burning Long term - skin cancer

Question 40

What are the systemic therapy treatments for psoriasis.

Answer 40

Immunosuppressants (methotrexate and ciclosporin) Oral retinoids (aciretin) Hydroxycarbamide Fumaric acid esters (Shifts T1 immune response to Th2) Biologics - infliximab (anti-TNF - dampens autoinflammation)

Question 41

What are the side effects of bioligcal therapy?

Answer 41

Liver dysfunction, hypertension and risk of infection