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Flashcards in Dermatitis Deck (45)
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1
Q

What do you give for allergic rash

A

Anti-histamine
Steroid
Query urticaria ??

2
Q

Where is dermatitis and where does it tend to affect

A

Papules and vesicles on erythematous base
Flexures
Face and neck in baby

3
Q

What can causes be

A

Endogenous
- Atopic = most common
Exogenous

4
Q

What is pathology behind atopic dermatitis

A

Genetics - FH atopy
Enviornment
Epidermal barrier dysfunction due to fliggarin dysfunction that allows allergens and irritants to enter causing immune response and water to be lost

5
Q

What genetics

A

Fligarrin gene
Fliggarin binds keratin and produces moisture
Atopic FH - asthma / hay fever / food allergy

6
Q

What histology

A

Spongiosis (intracellular oedema) within epidermis
Acanthosis (thickening of epidermis)
Inflammation

7
Q

What is classification of atopic

A

Itchy skin condition in last 2 months + 3 of

  • Onset <2
  • Flexural involvement
  • Hx dry skin
  • Hx atopy
8
Q

What are clinical features

A
Itchy dry skin condition
Affects flexures
Face, eyelids + neck = common in infants 
Antecubital and popliteal fossa 
Can affect wrist, hands and ankles 
Tend to spare nappy area
9
Q

What are acute changes

A
Erythema
Dry scale patches 
Papule
Vesicules
Weepy (Exudative)
Exudates, crusting and excoriation
10
Q

What are chronic changes

A

Lithification - papular eruption due to scratching / thickening
Plaque
Fissures
Hypo and hyper pigmentation

11
Q

What are nail changes

A

Ridging
Pitting
Paronychia
Onycholysis

12
Q

What causes acute flares

A
Viral illness
Stress
Environment
Food allergy
Pet allergy 
Teething
13
Q

What are exogenous types of exzema

A

Allergic Contact = child sensitised
Irritant contact = repeat contact
Lichen simplex
Photoallergic

14
Q

What causes contact dermatitis

A

Irritant or allergic
Type 4 hypersensitivity
APC takes allergic to LN and present to T cells

15
Q

What are features

A

Can take 48-72 hours to develop
Erythema common
Crusting and vesicles are rare

16
Q

How can you Dx

A

Skin patch set with potential allergen
IgE
Skin swab

17
Q

How do you Rx

A

Potent steroid

18
Q

What are other endogenous causes

A
Discoid
Venous / varicose 
Seborrheic
Pomphoylx
Asteatotic Eczema herpeticum
19
Q

What is discoid

A

Circular plaques of eczema

Can develop at trauma / irritation sites

20
Q

What cause venous eczema

A
Increased venous pressure due to venous stasis 
Lymph oedema
Varicose veins
Chronic swelling
RT in children
21
Q

What helps

A

Emollient
Topical steroids
Compression stockings

22
Q

What does seborrheic dermatitis tend to affect

A

Affects areas rich in sebaceous glands
Scalp / proximal flexures / face
Usually <6 months and clears without Rx
In adults associated with Malasseizia yeast

23
Q

What are features

A

Erythematous, sharply marginated lesions
Dermatitis + dry crusted skin
Covered with greasy looking scales
In children causes cradle cap (dry, flaky, erythematous with coarse yellow scale)

24
Q

What may develop in children

A

Otitis externa

Blepharitis

25
Q

What is associated in adults

A

HIV - test if severe
Parkinsonism
- can improve with L-dopa

26
Q

How do you Rx

A

Cradle cap

  • Baby oil then brushing of or white petroleum jelly over night
  • Topical anti-fungal if doesn’t work

Scalp

  • Anti-fungal shampoo
  • Topical steroid if severe itch

Face and body

  • Topical anti-fungal
  • Topical steroid short term
  • Recurrence common
27
Q

What is pomphoylx eczema and what does it require

A
Very itch 
Sudden onset crops of vesicles
Palms and soles
Can lead to desquamation
Requires intense steroid
28
Q

What is asteatotic eczema

A

Very dry skin
Common with hot climate or excessive washing
Shins commonly involved

29
Q

What causes eczema herpeticum

A

Disseminated viral infection - HSV or VZV on top of eczema

Common in children with atopic eczema where virus is able to enter skin

30
Q

How does it present

A
Itchy clusters of blisters and erosions
Widespread painful vesicular rash
Fever
Lethargy
Irritable 
NOT itchy
Swollen LN / lymphadenopathy
31
Q

How do you Rx

A

Can swab to confirm
Oral or IV acyclovir if severe
Ax if bacterial superinfection on top

32
Q

What is maintenance Rx for atopic dermatitis

A

Avoid exacerbating factor
Emollient (moisturer) to create artificial barrier
Soap substitute
Intermittent topical steroid for flare up = main stay

33
Q

How d you treat flare up’s

A

Thicker emollient
Topical steroid
Wet wraps of emollient left over night
Treat any complications e.g. bacterial infection
IV Ax or oral steroid may be required in very severe

34
Q

What are different potencies of steroid and what should you aim for

A

Weakest cream which controls symptoms for shortest period of time
Use once daily then alternate days
Can ue 2x daily if stubborn

Hydrocortisone = mild
Eumovate = moderate
Betamethasone = potent
Dermovate = very potent
35
Q

What are other Rx options

A
Calcineurin inhibitors - topical tacrolimus
UVB light / phototherapy 
Coal tar
Immunosuppression
- Steroid if severe and non-responsive 
- Methotrexate
- Azathioprine
- Ciclosporin 
Biologic = last resort
36
Q

What may you need depending on cause

A

Anti-histmiane if allergic for symptom relief
Anti-microbial if infection on top
Anti-viral if HSV

37
Q

What if future

A

Biologics

38
Q

What suggests will have severe eczema

A
3-6 months affected
Severe childhood
Associated atopy
Small family
High IgE
39
Q

What is very common on top of eczema

A
Bacterial infection - crusted / weepy
Can get viral infection
- Molluscum contagiosa
- Viral warts
- Eczema herpeticum
40
Q

How do you treat

A

FLucloxacillin

41
Q

In contrast to contact dermatitis how would you test for food allergy

A
Diary
IgE
Skin prick = most snesitive
Patch
Dietary elimination
42
Q

What is immediate reaction in allergy

A
Lip swelling
Urticaria
Facial redness and itchy
Angioedema 
Anaphylaxis
43
Q

What is late reaction

A
Worsening of eczema unresponsive to Rx
GI problems
FTT
Severe generalised itch 
If this happens think food allergy
44
Q

What should children with unresponsive exzemca get

A

Rx of hydrolysed milk especially if FTT / GI symptoms

45
Q

DDX of itchy eruption

A
Eczema
Psoriasis
Scabies
Urticaria 
Allergic reaction 
Autoimmune - lichen Plansu