Dermatology Flashcards
1
Q
functions of the skin
A
STAIN B
Storage Thermoregulation Aesthetics + communication Immunological Neurological Barrier/protection
2
Q
describe a rash structure
A
distribution - where is it:
- flexures/ extensors
- dermatomal
- intertriginous (folds of skin e.g. under breasts)
- photodistribution
configuration - grouping of the rash:
- linear
- annular (ring shaped)
- discoid (like a disc)
- clusters (infections!)
morphology - describe it
3
Q
describe a skin lesion struction
A
Asymmetry Border: irregular/regular Colour Diameter Elevation/everything else
4
Q
Eczema
aka
A
dermatitis
5
Q
Eczema
acute dermatitis
A
rapidly evolving red rash which may be blistered or swollen
6
Q
Eczema
chronic
A
longstanding irritable area
often darker, thickened (lichenified) and much scratched
7
Q
Eczema
sub-acute
A
an inbetween state
8
Q
Eczema
RFs (4)
A
- allergic rhinitis
- asthma
- age <5yrs
- FH of eczema
9
Q
Eczema
where does it present in infants
A
extensors
cheeks
forehead
scalp
10
Q
Eczema
where does it present in children and adults
A
flexures
11
Q
Eczema
signs and symptoms
A
- pruritis
- xerosis (dry skin)
- erythematous
- scaly
- excoriations
- lichenification
12
Q
Eczema
what does crust and weeping suggest
A
infections from staphylococcus
13
Q
Eczema
what is atopic eczema
A
- prevalent in children
- FH of dermatitis or asthma
14
Q
Eczema
what is allergic contact dermatitis
A
skin contact with substances that most ppl don’t react to
- nickel
- perfume
- rubber
- half dye
15
Q
Eczema
what is irritant contact dermatitis
A
- provoked by bodily fluids, water, detergents, solvents/harsh chemicals, friction
- worse if has atopic eczema
16
Q
Eczema
what is seborrheic dermatitis
A
irritation from toxic substances produced by Malassezia yeasts that live on the scalp and face
17
Q
Eczema
what is nummular dermatitis
A
aka discoid
- may be set off initially by an injury
- scattered coin-shaped irritable patches
- persist for a few months
18
Q
Eczema
what is gravitational dermatitis
A
- arises on lower legs of elderly
- due to swelling + poorly functioning leg veins
19
Q
Eczema
what is infective dermatitis
A
provoked by impetigo (bacterial infection) or fungal infection
20
Q
Eczema
trx for an acute flare
A
- emollients TDS
and
- topical corticosteroids (intermittent) e.g. hydrocortisone BD
21
Q
Eczema
trx for chronic
A
- emollients
- continuous low-mid potent topical corticosteroid
- reduce exposure to triggers
- immunosuppressive agents
- biologics
- antihistamines, phototherapy, abx
22
Q
Psoriasis
what is it
A
chronic autoimmune disease characterised by well demarcated, erythematous scaly plaques
23
Q
Psoriasis
what are the different types
A
- chronic plaque
- flexural
- guttate
- pustular
- generalised/erythrodermic
24
Q
Psoriasis
describe chronic plaque psoriasis
A
most common
- symmetrical plaques
- extensor (knees + elbows), scalp, lower back
- itchy
- well dermarcated circular to oval
- bright pink elevated lesion (plaque) w/ overlying white/silvery scale
25
Psoriasis
describe flexural (inverse) psoriasis
- smooth, erythematous plaques without scale
| - in flexures + skin folds
26
Psoriasis
describe guttate psoriasis
- multiple, small tear dropped erythematous plaques
- on trunk
- after strep infection
- young adults
27
Psoriasis
describe pustular psoriasis
- multiple petechiae + pustules
| - on palms + soles
28
Psoriasis
what is generalised/erythrodermic psoriasis
- rare but serious form
| - erythroderma + systemic illness
29
Psoriasis
nail changes (3)
- nailbed pitting
- onycholysis
- sublungual hyperkeratosis
30
Psoriasis
nail changes: what is nailbed pitting
superficial depression in nailbed
31
Psoriasis
nail changes: what is onycholysis
seperation of nail plate from nail bed
32
Psoriasis
nail changes: what is subungual hyperkeratosis
thickening of nailbed
33
Psoriasis
RFs (4)
- FH
- HIV
- obesity
- smoking
34
Psoriasis
triggers
- skin trauma
- infection: strep, HIV
- drugs
- withdrawal of steroids
- stress
- alcohol + smoking
- cold/dry weather
35
Psoriasis
what is Koeber phenomenon
skin lesions occur at sites of skin injury (inc lichen planus + vitiligo too)
36
Psoriasis
which drugs can trigger psoriasis
BALI
BB
ACEi, anti-malarials (hydroxychloroquine)
Lithium
Indomethacin/NSAIDs
37
Psoriasis
chronic plaque mnx 1st line
```
regular emollient
+
potent corticosteroid (topical) OD
+
vit D analogue (topical) OD
```
38
Psoriasis
chronic plaque mnx 2nd line
vit D analogue BD
39
Psoriasis
chronic plaque mnx 3rd line
potent corticosteroid BD for up to 4w
or
coal tar preparation (OD/BD)
short acting dithranol can also be used
40
Psoriasis
systemic trx
1st: methotrexate
2nd: ciclosporin
3rd: Acitretin
41
Psoriasis
systemic trx: why monitor LFTs if giving methotrexate
hepatotoxicity
42
Psoriasis
systemic trx: why monitor FBCs if giving methotrexate
myelosuppression --> pancytopenia
43
Psoriasis
systemic trx: when can ciclosporin be used 1st line
```
if rapid control needed
or
palmoplantar pustulosis
or
considering conception
```
44
Psoriasis
systemic trx: what are the SE's of ciclosporin
5 H's
- hypertrophy of gums
- hypertrichosis
- HTN
- Hyperkalaemia
- Hyperglycaemia
45
Psoriasis
systemic trx: what are the SE's of Acitretin
- teratogenic
- hepatotoxicity
- increased lipids
46
Psoriasis
1st line phototherapy
narrowband UVB
47
Psoriasis
2nd line phototherapy
psoralen + UVA (PUVA)
48
Psoriasis
SE's of phototherapy
- skin aging
| - squamous cell cancer (not melanoma)
49
Psoriasis
what biological therapy can be used
- Infliximab
- Etanercept
- Adalimumab
50
Psoriasis
biological therapy: what is associated with Adalimumab
reactivation of latent TB
51
Acne Vulgaris
what is it
an inflammatory disease of the pilosebaceous unit
52
Acne Vulgaris
what is the pilosebaceous unit
hair follicles and sebaceous gland
53
Acne Vulgaris
how do non-inflammatory lesions present as
cornedones
54
Acne Vulgaris
how do less severe inflammatory lesions present as
papules
| pustules
55
Acne Vulgaris
how do severe inflammatory lesions present
nodules
cyst
scarring
56
Acne Vulgaris
what is mild acne
- non inflammatory lesions
| - w/ sparse inflammatory lesions
57
Acne Vulgaris
what is moderate acne
- widespread non inflammatory lesions
| - w/ numerous papules + pustules
58
Acne Vulgaris
what is severe acne
- extensive inflammatory lesions
| - inc nodules, pitting and scarring
59
Acne Vulgaris
aetiology
- ↑ sebum production
- ↑ androgens -> hyperplasia of sebaceous glands
- hyperactive immune response
- bacterial colonisation
60
Acne Vulgaris
complications
- post inflammatory pigmentation
- scarring
- deformity
- psychological + social effects
61
Acne Vulgaris
1st line (mild) mnx
topical benzoyl peroxide
62
Acne Vulgaris
2nd line (mild) mnx
topical abx or topical retinoid
63
Acne Vulgaris
3rd line (mod) mnx
- PO tetracyclines
or
- PO anti-androgens
64
Acne Vulgaris
3rd line (mod) mnx: name some tetracyclines
- lymecyline
- oxtetracycline
- doxycycline
65
Acne Vulgaris
3rd line (mod) mnx: CI's of tetracyclines
avoid in pregnant/breastfeeding women
avoid if <12 years
66
Acne Vulgaris
3rd line (mod) mnx: which abx can you used instead of tetracyclines in pregnant/breastfeeding women
erythromycin
67
Acne Vulgaris
3rd line (mod) mnx: what is the max duration of PO abx
3m
68
Acne Vulgaris
3rd line (mod) mnx: SE of long term abx use and what do you give if it occurs
gram -ve folliculitis
give high dose PO trimethoprim
69
Acne Vulgaris
3rd line (mod) mnx: name some PO anti-androgens
- OCP
| - spironolactone
70
Acne Vulgaris
4th line (severe) mnx
PO retinoid
| e.g. isotretinoin
71
Acne Vulgaris
4th line (severe) mnx: SEs of PO retinoid
- highly teratogenic
- hepatitis (moniter LFTs)
- dry mucous membrane
- headache
- hair thinning/loss
72
Rosacae
features
- 1st sx: flushing
- then persistent erythema w/ pustules + papules
- telangiectasia
- rhinophyma (large, red, bumpy nose)
73
Rosacae
where does it typically affect
nose, cheeks, forehead
74
Rosacae
how does it involve the eye
blepharitis
75
Rosacae
epidemiology
30-60yrs
F>M
common in pale skins
76
Rosacae
exacerbating factors
- sunlight
- hot weather
- warm baths
- stress
- spicy foods
77
Rosacae
mnx (general measures)
- camourflage creams
- sun protection
- avoid exacerbating factors
- emollient as a soap substitute if skin is dry
78
Rosacae
1st line mnx (mild)
topical metronidazole
79
Rosacae
what classes it as mild
limited number of papules and pustules and no plaque
80
Rosacae
2nd line mnx (for predominant flushing but limited telangectasia)
topical Azelaic acid / Brimonidine / Ivermectin
81
Rosacae
what can be used to manage persistent telangiectasia
laser therapy
82
Rosacae
mnx for severe cases
systemic abx: PO tetracyclines e.g. ocytetracycline
83
Viral Warts
where can they present on the body
cutaneous (aka veruca papilloma)
mucosal
84
Viral Warts
describe a cutaneous wart
- hard keratinous surface
| - papillary capillaries (tiny red/black dots visible on wart)
85
Viral Warts
cause
- infection by HPV
| - direct skin to skin contact or autoinoculation
86
Viral Warts
common wart
cauliflower like papulae
87
Viral Warts
plantar
- sole
| - caused by HPV1, 2
88
Viral Warts
plane
- multiple small flat topped skin coloured papules
| - often spread shaving
89
Viral Warts
filiform
- cluster of fine fronds emerging from pedicle base
| - face
90
Viral Warts
butcher's
HPV 7 infecting butcher's hand
91
Viral Warts
epidermodysplasia veruciforms
- rare autosomal recessive
92
Viral Warts
mnx
- topical paints containing salicylic acid or podophyllin
- cryotherapy
- electrosurgery (curettage + cautery) for large resistant warts
93
cause of genital warts
HPV 6 or 11
| spread by skin to skin contact
94
mnx of epidermoid and pilar cysts
none - most disappear
| if red hot --> infected --> flucloxacillin
95
epidermoid cyst
location
face, neck, trunk
96
epidermoid cyst
central punctum?
yes
97
epidermoid cyst
origin
epithelium or hair follicle infundibulum
98
epidermoid cyst
cyst wall
delicate and prone to rupture
99
epidermoid cyst
histology
granular layer
100
epidermoid cyst
which syndrome is it present in
Gardner Syndrome
101
pilar cyst
location
scalp and scrotum
102
pilar cyst
central punctum?
no
103
pilar cyst
origin
outer root sheath
104
pilar cyst
cyst wall
thick + not prone to rupture
105
pilar cyst
histology
granular layer is absent
106
pilar cyst
what does it contain
keratinous material
107
pilar cyst
inheritance pattent
often autosomal dominant
108
Seborrhoeic Keratosis
what is it
a harmless warty spot and a common sign of skin ageing
109
Seborrhoeic Keratosis
presentation
- 'stuck on' appearance
- large variation in colour from flesh to light-brown to black
- fissured keratin surface.
110
Seborrhoeic Keratosis
mnx
- leave alone
- cryotherapy
- shave biopsy
- curettage
111
Dermatofibroma
what is it
a common benign fibrous nodule usually found on the skin of the lower legs
occurring at sites of previous trauma (insect bite)
112
Dermatofibroma
size
7-10mm
113
Dermatofibroma
presentation
- tethered to skin surface + mobile over sc tissue
- sometimes painful, tender, itchy
- Pinch Sign
- solitary dermal nodules
114
Dermatofibroma
what is Pinch Sign
the overlying skin dimples on pinching the lesion
115
Dermatofibroma
mnx
reassure
116
Dermatofibroma
histology
- proliferating fibroblasts
| - merging w/ sparsely cellular dermal tissues
117
Shingles
cause
reactivation of the varicella zoster virus which an lie dormant in nerve ganglia following primary infection (chickenpox)
118
Shingles
commonly effects who?
elderly + young adults
119
Shingles
prodromal period features
- burning pain over affected dermatome
| - fever, headache, lethargy
120
Shingles
which is the most commonly affected dermatome
T1-L2
121
Shingles
describe the rash
initially erythematous, macular rash over affected dermatome
becomes vesicular
well demarcated by the dermatome
doesn't cross midline
122
Shingles
whom should pts avoid
pregnant women + the immunosuppressed
123
Shingles
when are pts infectious till
until the vesicles have crusted over
usually 5-7d following onset
124
Shingles
mnx to reduce risk of spread
cover lesions
125
Shingles
mnx: analgesia
1st line: NSAIDs + paracetamol
consider amitriptyline
severe + immunocompetent: PO corticosteroids 2w
126
Shingles
mnx
antivirals within 72hrs (aciclovir)
unless <50y + mild truncal rash w/ mild pain + no underlying RFs
127
Shingles
what is the most common complication
post herpetic neuralgia
128
Shingles
complications other than post herpetic neuralgia
herpes zoster opthalmicus
herpes zoster oticus (Ramsay hunt syndrome) - HHV3 infection of the facial nerve
129
Shingles
what is herpes zoster opthalmicus
a complication.
shingles affecting the ocular division of the trigeminal nerve
130
Lichen planus
what is it
an autoimmune condition that causes localised chronic inflammation
131
Lichen planus
describe the rash
itchy, papular rash
polygonal in shape
Wickham's striae: white lines pattern on the surface
Koebner phenomenon
132
Lichen planus
where is the rash most common
on the palms, soles, genitalia and flexor surfaces of the arms
133
Lichen planus
what may be seen in the mouth
white-lace pattern on the buccal mucosa
134
Lichen planus
nail features
longitudinal ridging (onychorrhexis)
thinning of nail plate
135
Lichen planus
lichenoid drug eruption causes
- gold
- quinine
- thiazides
136
Lichen planus
mnx
- potent topical steroids
137
Lichen planus
mnx for oral lichen planus
benzydamine mouthwash or spray
138
Actinic Keratoses
what is it
a common premalignant skin lesion that develops as a consequence of chronic sun exposure
pre cursors for SCCs
139
Actinic Keratoses
RFs
- type I or II skin
- hx of sunburn
- outdoor occupation or hobbies
- immunosuppression
140
Actinic Keratoses
describe it
thickened papules or plaques w/ surrounding erythematous skin + a keratotic, rough warty surface
141
Actinic Keratoses
common location
- temple of head
| - back of head
142
Actinic Keratoses
mnx for localised lesions
cryotherapy, curettage or surgical excision
143
Actinic Keratoses
mnx for larger lesions
- topical S-Fluorouracil (cytotoxic agent)
- topical imiquimod (modifies immune response)
- topical diclofenac (NSAID for mild AK)
144
Bowen's disease
what is it
a type of precancerous dematosis that is a precursor to SCC
| more common in older patients
145
Bowen's disease
features
- irregular, red, scaly plaques
- often 10-15mm
- on sun exposed areas: temple, neck, lower limbs
- slow growing
146
Bowen's disease
mnx
- top 5-flurouracil
- top steroids
- cyro, excision
147
what is the most common form of skin cancer
BCC
148
Basal Cell Carcinoma
which type of BCC is most common and name some others
```
most common: nodular
superficial
pigmented
cystic
keratotic
morphoeic
```
149
Basal Cell Carcinoma
presentation of a nodular BCC
- Pearly / shiny nodule with a smooth surface
- small, skin coloured/pink nodule w/ central depression
- surface telangiectasia
- head + neck
150
Basal Cell Carcinoma
mnx
- surgical excision w/ 4mm margin
- curettage + cautery
- cryo
- top: imiquimod, fluorouracil
- radiotherapy
151
Squamous Cell Carcinoma
presentation
- irregular ill-defined red nodule
- scale + ulceration
- rapidly growing
152
Squamous Cell Carcinoma
causes
- UV light
- human wart virus
- burns
- genetic
lead to DNA mutations
153
Squamous Cell Carcinoma
what makes it a good prognosis
- well differentiated tumour
- <20mm in diameter
- <2mm deep
- no associated diseases
154
Squamous Cell Carcinoma
what makes a bad prognosis
- poorly differentiated tumours
- >20mm in diameter
- >4mm deep
- immunosuppression
155
Squamous Cell Carcinoma
mnx
- lesion <20mm: surgical excision w/ 4mm margin
- >20mm: surgical excision w/ 6mm margin
- Mohs micrographic surgery if in cosmetically important sites
156
Malignant Melanoma
if any lesion has ____, you should refer urgently under 2w wait pathway
```
Asymmetry
Border irregularity
Colour variation
Diameter >6mm
Evolves over time
```
157
Malignant Melanoma
what are the types
- superficial spreading
- nodular
- lentigo maligna
- acral lentiginous
158
Malignant Melanoma
superficial spreading:
- common?
yes 70% of cases
159
Malignant Melanoma
superficial spreading: typically affects?
- young ppl
| - arms, legs, back, chest
160
Malignant Melanoma
superficial spreading: appearance
- growing moles
| - usually grows horizontally first
161
Malignant Melanoma
dx
- dermatoscope
| - excisional biopsy --> histology for dx + establish Breslow thickness
162
Malignant Melanoma
trx
- wider excision margin around lesion
163
Malignant Melanoma
trx for stage III + IV (metastatic)
- adjuvant immunotherapy + chemo
164
Malignant Melanoma
further inx if Breslow Thickness >1mm
sentinal node biopsy (to look for metastases + stage the cancer)
165
Scabies
cause
by the mite Sarcoptes scabiei
166
Scabies
pathphysiology
- Sarcoptes scabiei burrows into skin
- lays eggs in the stratum corneum
- 30d later: delayed type 4 hypersensitivity reaction to mites/eggs
- intense puritis
167
Scabies
features
- widespread pruritis
- linear burrows on hands
- classically worse at night
- excoriation, infection due to scratching
- papular vesicular
168
Scabies
1st line trx
top permethrin 5%
leave on for 12h before washing off
for 7d
169
Scabies
2nd line trx
malathion 0.5%
leave on skin for 24h
170
Scabies
trx for all contacts
all should be treated even if asymptomatic
171
Tinea
what is it
dermatophyte fungal infections
172
Tinea
what are the types
- tinea capitis (scalp ringworm)
- tinea corporis (ringworm)
- tinea pedis (athlete's foot)
- tinea incognita
173
Tinea
what is tinea corporis (ringworm)
itchy annular lesions with clear, defined, raised, scaly edge
174
Tinea
what is tinea capitis
Scalp ringworm: Patches broken hair, scaling and inflammation
175
Tinea
what is tinea pedis
athlete's foot: Moist scaling and fissuring in toewebs
176
Tinea
what is tinea incognita
inappropriate treatment of tinea with corticosteroids, causing a different appearance
may occur when rash is wrongly diagnosed as dermatitis initially
177
Tinea
establish dx with?
skin scraping, swabs or hair/nail clippings
178
Tinea
mnx
- top antifungal: terbinafine cream, ketoconazole/selenium sulphate shampoo
- PO antifungal: itraconazole, fluconazole
179
Impetigo
clinical features
- golden crusted lesions around mouth
- pruritic rash
- v. contagious
180
Impetigo
common cause
staph aureus
strep pyogenes
181
Impetigo
who is it common in
children
182
Impetigo
mnx for pts NOT systemically unwell/high risk of complications
hydrogen peroxide 1% cream
183
Impetigo
mnx
- top fusidic acid
- intranasal mupirocin
- PO flucloxacillin
184
Impetigo
what should children do about school
exclude from school until lesions are crusted and healed
or 48h after abx trx
185
Cellulitis & Erysipelas
what is the difference
cellulitis: acute bac infection of dermis + SC tissue
erysipelas: more superficial infection
186
Cellulitis & Erysipelas
organisms
staph aureus, strep pyogenes
187
Cellulitis & Erysipelas
presentation
- warmth, pain, erythema, swelling
- blisters may form
- usually lower limb
- generally unilateral
188
Cellulitis & Erysipelas
inx
- FBC (raised WCC)
- blood culture
- purulent focus culture
- CT/MRI if orbital cellulitis suspected
189
Cellulitis & Erysipelas
mnx
flucloxacillin PO
190
Cellulitis & Erysipelas
comlications
- local tissue damage
- sepsis
- orbital cellulitis
191
well-defined circular papules on which evolve at different stages to form a 'target-shaped' lesion of three concentric rings of different colours. The rash starts on the palms/soles and spread up the limbs to the trunk. what is it
erythema multiforme (could be caused by HSV)
192
what is psoriasis relieved by
exposure to sun
193
pruritic papulovesicular lesions over the buttocks and extensor surfaces of the arms, legs, and trunk. Diarrhoea for a few months. What could this be
dermatitis herpetiformis (assc w/ coeliac disease)
194
mnx of pruritic sx of Dermatitis Herpetiformis
Dapsone (an abx)
| and a gluten free diet
195
mnx of staph scalded skin syndrome
IV vancomycin
196
trx of psoriasis on scalp
3% salicylic acid cream in combination with a tar-containing shampoo.
197
Pemphigus vulgaris
what is it
an autoimmune disease caused by antibodies directed against desmoglein 3, a cadherin-type epithelial cell adhesion molecule
198
Pemphigus vulgaris
which molecule is affected by the attacking antibodies
desmoglein 3
199
Pemphigus vulgaris
which population is commonly affected
Ashkenazi Jewish population
200
Pemphigus vulgaris
features
- mucosal ulceration
- skin blistering
- flaccid, easily ruptured vesicles and bullae
- typically painful but not itchy
- Nikolsky sign positive
201
Pemphigus vulgaris
what will biopsy show
acantholysis (loss of coherence between epidermal cells due to the breakdown of intercellular bridges)
202
Pemphigus vulgaris
mnx
steroids are first-line
| immunosuppressants
203
Bullous pemphigoid
what is it
an autoimmune condition causing sub-epidermal blistering of the skin
204
Bullous pemphigoid
which proteins are attacked by antibodies
hemidesmosomal proteins BP180 and BP230
205
Bullous pemphigoid
who is it more common in
elderly patients
206
Bullous pemphigoid
features
- itchy, tense blisters typically around flexures
- blisters usually heal without scarring
- no mucosal involvement (i.e. the mouth is spared)
207
Bullous pemphigoid
what will skin biopsy show
immunofluorescence shows IgG and C3 at the dermoepidermal junction
208
Bullous pemphigoid
mnx
- PO corticosteroids
| - topical corticosteroids, immunosuppressants and antibiotics are also used
209
Bullous pemphigoid
complications
- Bacterial staph + strep skin infection, and sepsis
- Viral infection with herpes simplex, varicella or herpes zoster
- Complications of treatment
210
Bullous pemphigoid
inx
- Direct immunofluorescence staining of a skin biopsy
| - bloods: indirect immunofluorescence test for circulating pemphigoid BP180 antibodies
