Inflammatory Skin Disease Flashcards
(107 cards)
1
Q
What is rosacea
A
A condition where blood vessels of the face dilate.
2
Q
Cause of rosacea
A
Unknown!
Certain triggers:
sunlight, alcohol, spicy food, stress
3
Q
Presentation of rosacea
A
Fixed central erythema of face Mild or moderate papules pustules Rhinophyma - skin thickening of nose Telangiectasia Ocular involvement - blepharitis, keratitis, conjunctivitis
4
Q
Ix of roacea
A
Clinical diagnosis
5
Q
Tx rosacea
A
Topical Abx for localised disease:
- topical metronidazole
- azelaic acid
- brimonidine gel
Systemic Abx for more severe disease:
- tetracycline
- isotretinoin
6
Q
3 main autoimmune causes of skin blistering
A
Pemphigus
Bullous pemphigoid
Dermatitis Herpetiformis
7
Q
What skin level does blistering in pemphigus occur in
A
Intra-epidermal
8
Q
What skin level does blistering in bullous pemphigoid occur in
A
Sub-epidermal
9
Q
What skin level does blistering in dermatitis herpetiformis occur in
A
Sub-epidermal
10
Q
Investigation for autoimmune causes of blistering
A
Biopsy with immunofluorescence
11
Q
Most common autoimmune bullous disease
A
Bullous pemphigoid
12
Q
Presentation of bullous pemphigoid
A
Large tense bullae on normal skin or erythematous base
Bullae burst to leave erosions - no scarring
Itchy erythematous plaques and papules may preceed bullae formation by 3-4 months (so may be the only presenting feature!)
13
Q
How many biopsies are taken for the investigation of bullous pemphigoid and where are they taken from
A
1 for histology - taken from a small intact blister
1 for immunofluoresence - taken from normal skin adjacent to blister
14
Q
Pathogenesis of bullous pemphigoid
A
Patients circulating IgG antibodies react with antigens in the BM and hemidesmosomes anchoring basal cells to BM
results in complement activation and deposition around the BM
15
Q
Histological appearance of bullous pemphigoid
A
Subepidermal bullae with lots of eosinophils
16
Q
IMF appearance of bullous pemphigoid
A
Linear deposition at DEJ
17
Q
Tx of bullous pemphigoid
A
Localised disease:
- topical steroids (clobetasol - v potent)
- topical tacrolimus
Generalised disease:
- oral steroids (prednisolone) (0.5-1mg/kg) - 40-80mg/day
18
Q
prognosis of bullous pemphigoid
A
chronic and self-limiting
most have remission in several months
19
Q
What age group of patients usually get bullous pemphigoid
A
elderly
20
Q
What age group of patients usually get pemphigus vulgaris
A
Middle aged
21
Q
presentation of pemphigus vulgaris
A
flaccid blisters that can be burst easily to form erythematous erosions
22
Q
most common locations for pemphigus vulgaris to present
A
face, scalp, axillae, oral mucosa, groin
23
Q
What is Nikolsky sign
A
firm pressure to the top layer of skin detaches the top layer
- positive in pemphigus
- negative in bullous pemphigoid
24
Q
Most common complication of pemphigus vulgaris
A
secondary infection of deroofed blisters
25
Histological appearance of pemphigus
cleavage within epidermis with eosinophil infiltration
26
Pathogenesis of pemphigus vulgaris
IgG antibodies are directed against intercellular adhesions - acantholysis
27
Immunofluorescence of pemphigus vulgaris
"chicken wire" appearance - due to acantholysis - lysis of intercellular adhesion sites
28
Tx of pemphigus vulgaris
Localised disease:
- topical steroids
```
Systemic disease (more likely to need this):
- oral steroids - prednisolone
+/-
azothioprine
dapsone
ciclosporin
plasmapharesis
```
29
what is dermatitis herpetiformis
autoimmune blistering disorder associated with COELIAC DISEASE
30
Common sites of involvement of dermatitis herpetiformis
extensor aspects of elbows and forearms
buttocks and scapulae
extensor aspects of knees
face and scalp
31
presentation of dermatitis herpetiformis
small blisters on erythematous urticarial base
itch - precedes blistering
excoriations - burst blisters
grouping of lesions (like herpes)
32
Ix for dermatitis herpetiformis
Coeliac serology
| Skin biopsy with immunofluorescence
33
Histological appearance of dermatitis herpetiformis
Subepidermal blister
| microabscesses in dermal papillae
34
Immunofluorescence appearance of dermatitis herpetiformis
granular IgA deposits in dermal papillary
35
Tx of dermatitis herpetiformis
gluten free diet
| dapsone
36
complication of dermatitis herpetiformis
small bowel lymphoma
37
What is psoriasis
chronic relapsing and remitting inflammatory skin disorder where there is HYPERPROLIFERATION OF EPIDERMAL CELLS
38
Cause of psoriasis
Exact cause unknown
Gene variants + environmental insults
39
Pathogenesis of psoriasis
Increased number of epidermal cells entering cell cycle from the basal layer - therefore faster epidermal turnover time
40
Epidermal turnover time in psoriasis
5 days
41
Normal epidermal turnover time
25 days
42
Plaques in psoriasis - sterile or non-sterile
STERILE!! swabs will grow nothing if pustules are present
43
precipitating factors of psoriasis
1. Emotional stress
- infection
- drugs
- alcohol
- trauma
- smoking
- HIV/AIDS
- cold weather
44
What drugs can precipitate psoriasis
Lithium ****
B blockers ***
Anti-malarials
45
Name for when there has been trauma to the skin, then psoriasis develops around it
Koebner phenomenon
46
What are Munro microabscesses
Clumps of leucocytes in the stratum corneum - seen in psoriasis
47
Histological appearance of psoriasis
Parakeratosis (i.e. nucleated keratinocytes in stratum corneum)
absence of granular layer
expanded prickle cell layer
elongation of rete ridges
leucocytes - munro microabscess in stratum corneum
48
What causes elongation of rete ridges in psoriasis
large dilated vessels in papillary dermis
49
List the 10 different possible presentations of psoriasis
1. chronic plaque
2. guttate
3. flexural
4. scalp
5. palmoplantar
6. palmo plantar pustolosis
7. erythrodermic
8. generalised pustular
9. nail
10. psoriatic arthritis
50
What is Auspitz sign
sign in psoriasis -
| removal of plaque reveals pin-point bleeding
51
What other conditions can Koebner phenomenon occur in, other than psoriasis
Lichen planus
| Vitiligo
52
What is guttate psoriasis
raindrop shaped multiple small psoriatic lesions on trunk
53
What is development of guttate psoriasis associated with
streptococcal sore throat 7-10 days before onset of symptoms
54
Sites of flexural psoriasis
groin
axillae
inframammary areas
55
Tx of flexural psoriasis
Mild topical steroid
56
What can flexural psoriasis be misdiagnosed as
fungal infection
| intertrigo
57
Tx of palmoplantar psoriasis
```
topical tar preparations
salicylic acid
topical steroids
phototherapy
systemic immunosuppressants
```
58
What is erythrodermic psoriasis
Uncommon sub type of psoriasis where >90% of skin surface is red
59
Causes of erythrodermic psoriasis
withdrawal of potent topical or systemic steroids, drug reactions, UV burns
60
Complications of erythrodermic psoriasis
```
hypothermia
cardiogenic shock
dehydration
anaemia
hypoproteinaemia
```
61
Tx of erythrodermic psoriasis
fluid balance
bed rest
emollients
systemic immunosuppressants
62
causes of generalised psutular psoriasis
withdrawal of steroids
infection
pregnancy
hypocalcaemia
63
Common nail changes in psoriasis
nail pitting
onycholysis
"oil-drop" lesions
subungual hyperkeratosis
64
1st line Tx of psoriasis
Emollients
65
What do emollients do for psoriasis
Remove scaling
66
Tx used for psoriasis along with emollients
Topical corticosteroids
67
How long should potent TCS be used for psoriasis Tx
Max 8 weeks at a time
68
How long should very potent TCS be used for psoriasis Tx
Max 4 weeks at a time
69
What length of time should patient wait between courses of TCS for psoriasis
4 week breaks
70
Tx of psoriasis on the face
Mild TCS - hydrocortisone
71
Max length of time TCS can be used on the face for psoriasis, and why is there a max lengh
1-2wks/month maximum
Face is prone to steroid atrophy
72
When is using potent steroids not suitable as a treatment for psoriasis
when the psoriasis is generalised -- risk of rebound flare up (pustular, erythroderma)s
73
If topical steroids do not work for psoriasis, what other topical Tx can be tried
1. Vitamin D analogues (Calcipotriol, Calcitriol)
2. Coal tar preparations
3. Dithranol
74
How do Vitamin D analogues work as a Tx for psoriasis?
Reduce cell division and differentiation - help with plaque removal but not erythema
75
Advantages of Vitamin D analogues for psoriasis Tx
clean and no odour
can be used long term unlike TCS
adverse s/e uncommon
76
How does coal tar work as a Tx for psoriasis
Reduces DNA synthesis and epidermal proliferation
77
Disadvantages of coal tar for psoriasis Tx
brown, smelly
| can stain and irritate
78
How does Dithranol work as a Tx for psoriasis
Anti-mitotic effect - only used on stable plaque psoriasis
79
Disadvantages of Dithranol for psoriasis Tx
can only be used for short contact regimes - burns skin
| stains clothing and bedding purple
80
Specialist Tx available for psoriasis
Phototherapy
| Systemic Tx
81
phototherapy Tx for psoriasis
Phototherapy (UVB)
- 3x week for 6-8 weeks
Photochemotherapy (UVA)
PUVA = psoralen + UVA
2x week
82
Adverse effects of PUVA Tx
skin ageing
| SCC
83
Systemic Tx for psoriasis
1. Methotrexate
2. Ciclosporin
2. Retinoids
4. biologics
84
What is pityriasis rosea
An acute self-limiting rash
85
Cause of pityriasis rosea
Unknown!
| ?Association with Herpes Hominis Virus 7 (HHV-7)
86
Presentation of pityriasis rosea
Herald patch - early single lesion
then scaly, oval erythematous patches with "fir tree" appearance of distribution
87
Tx of pityriasis rosea
None - self limiting that resolves in around 6 weeks
88
What is pityriasis rosea often misdiagnosed as
Guttate psoriasis
89
what is acne
common skin disorder characterised by keratin plugging of pilosebaceous units resulting in comedones, inflammation and pustules
90
What characterises mild acne
open and closed comedones (white and black heads) mostly, with some papules and pustules
91
Tx of mild acne
single topical Tx
- topical retinoid
- benzoyl peroxide
92
what characterises moderate acne
papules and pustules predominate
93
Tx of moderate acne
combined topical treatments
or
combine topical Tx and oral Abx
94
what characterises severe acne
nodules and cysts and inflammatory papules and pustules
95
Tx of severe acne
oral isotretinoin
96
What is erythema nodosum
Inflammation of subcutaneous fat
97
Causes of erythema nodosum
Infection - TB, Streptococci
Systemic disease - IBD, sarcoidosis, Behcet's
Malignancy
Drugs - sulphonamids, COC
Pregnancy
98
Presentation of erythema nodosum
Tender erythematous nodular lesions
Usually on shins - can also be forearms and thighs
99
Tx of erythema nodosum
1. Bed rest and elevation, Tx of underlying cause, analgesia
2. Potassium iodide
3. Intralesional corticosteroid injection
100
What is lichen planus
An inflammatory skin disorder of unknown cause!
101
Presentation of lichen planus
Pruritic, Purple, Polygonal shaped Papular rash (4 p's of lichen planus)
102
Appearance of Lichen planus in the mouth
Wickham's striae - white lace pattern of surface
103
Presentation of lichen planus in the nails
nail plate thinning, longitudinal ridging
104
What is Lichen Sclerosus
itchy white spots typically on the vulva of elderly women
105
Drugs causing lichenoid drug eruptions
Gold
Quinine
Thiazides
106
Management of lichen planus
1. Topical corticosteroids (clobetasol)
+
Antihistamines (chlorphenamine)
107
Tx of oral lichen planus
benzydamine mouthwash
