Dermatology Flashcards
1
Q
What are the different layers forming the skin?
A
- Stratum corneum
- Stratum lucidum
- Stratum granulosum
- Stratum spinosum
- Stratum basale
- Dermis
2
Q
What cells give skin it’s pigmentation and which layer do they lay in?
A
-Melanocytes in the basal layer
3
Q
When describing skin lesions how is it best to describe them?
A
- Distribution
- Configuration
- Morphology
4
Q
What are some distribution factors of skin lesions to consider?
A
-Where on the body it is? >Flexures ie eczema >Extensors ie psoriasis >On the face ie seborrhoeic >Dermatomoal ie shingles >Intertriginous ie in moist areas such as under the breast -Pattern >Symmetrical ie vitilgo
5
Q
What are some configuration factors of skin lesions?
A
- Linear
- Targetoid (3 concnetric rings ie erythema multiforme)
- Annular (ring shaped) ie tinea, ring worm, lupus
- Discoid ie discoid lupus
- Reticular ie livedo reticularis
- Clusters
6
Q
How can the morphology of a skin lesion be described?
A
- Macular (flat)
- Papule (raised)
- Plaque (elevated, well circumscribed raised area) ie psoriasis
- Nodule (big papule)
- Vesicle (small blister - if >5mm = bulla)
- Crust (dry blood/serum)
- Scale (hyperkeratosis)
7
Q
What is the most important diagnosis to consider with a skin lesion?
A
-Skin cancer
8
Q
What are the Fitzpatrick skin types
A
I: never tans, always burns (red hair, freckles, blue eyes
II: usually tans, always burns
III: always tans, sometimes burns (dark hair, brown eyes)
IV: always tans, rarely burns (olive skin)
V: Sunburn and tan after extreme UV exposure (brown skin)
VI: Black skin, never tans, never burns
9
Q
What is the most common type of skin cancer?
A
-Basal cell carcinoma
10
Q
What are the risk factors for basal cell carcinoma?
A
- UV exposure in the elderly (long time exposure)
- Fair skin
- Immune suppression
- Genetic factors
11
Q
What are the features of basal cell carcinomas?
A
- Shiny ‘pearly surface’
- Telangiectasia (branch line capilarries)
- Central nodule/’rodent ulcer’
- Surface ulceration
- Rolled edge
- Locally invasive (won’t met)
- Slow growing over 1+ year
12
Q
How are superficial BCCs managed?
A
- Creams if stay superficial
- Excision by Moh’s micrographic surgery >for ill-defined and large BCC on risky sites
- Radiotherapy
13
Q
What are risk factors/causes for malignant melanoma
A
- UV light exposure
- Fair skin (Fitzpatrick I or II)
- Red hair
- > 100 Naevi on body
- > 5 atypical naevi on body
- Family history
14
Q
What are features of malignant melanoma?
A
- Asymmetry
- Border irregularity
- Colour irregularity
- Diameter >6mm
- Evolving
15
Q
What is the most common type of melanoma?
A
-Superficial spreading
> others: nodular, lentigo maligna, melanoma of the nails
16
Q
What is the most important prognostic indicator for malignant melanoma?
A
-Breslow thickness
> Thickness of the melanoma. thicker = worse prognosis
17
Q
How is malignant melanoma treated?
A
- Excision
- Chemo, radio and immunlogical therapy for palliative pts with mets disease
18
Q
Where do malignant melanomas commonly metastasis to?
A
- Lungs
- Brain
19
Q
Which skin cancer is most likely to be keratotic and faster growing?
A
-Squamous cell carcinomas
20
Q
What are risk factors/causes for squamous cell carcinomas?
A
- UV light exposure over long time frame
- Immune suppression
- Actinic keratoses and Bowen’s disease
- Smoking
- Long standing leg ulcers
- Genetic conditions ie albinism, xeroderma pigmentosum
21
Q
What are features of squamous cell carcinoma?
A
- Potential to metastasise
- High risk sites: lips and ears
- Keratotic appearance
22
Q
How are SSCs treated?
A
- Surgical excision
- Moh’s micrographic surgery for high risk pts/cosmetic areas
23
Q
What are 3 types of ulcers seen on skin?
A
- Venous
- Arterial
- Neuropathic
24
Q
What are features of venous ulcers?
A
- Commonly over the medial malleolus
- May have varicose veins
- Haemosiderin patches/deposits in the skin
- Lipodermatosclerosis
- Venous eczema (dry/shiny)
25
How are venous ulcers managed?
- Compression bandages as 1st line
| - Refer to vascular surgery if not effective
26
What is the most important investigation to perform for skin ulcers?
-ABPI
>Normal: 0.9-1.2
>>Compression bandages should not be used if <0.9 as could lead to criticla limb ischaemia
27
What are features of arterial ulcers?
- Peripherally located at distal points, pressure sites
- Deep, punched out and necrotic
- Painful
- Shiny skin
- Increased cap refill time
- Absent pedal pulses
- Hypoperfusion signs ie lack of hair
- Risk factors for ateial disease
- Abnormal ABPI
28
How are arterial ulcers managed?
- Referral to vascular surgeons
- Exercise
- Modify CV Risk factors
29
What are the features of neuropathic ulcers?
- Most commonly seen in diabetes
- Commonly over plantar surface of the metatarsal head and hallux
- Occur on pressure sites
- Punched out/necrotic
- Caused by sensory impairment to the area
30
How are neuropathic ulcers treated?
- Education of diabetic foot health
| - Cushioned shoes and appropriate dressings to relieve pressure and reduce callous formation
31
What is the most common form of eczema/dermatitis?
-Atopic eczema
32
What are some triggers/causes of eczema?
- Dry skin
- Hot/cold temperatures
- Irritants
- Allergy
33
What are features of eczema?
- Patches of dry red itchy skin
- Adults/older children: flexor surfaces
- Babies: face and trunk
- Contact dermatitis: in distribution to exposure
34
How is eczema managed?
- Emollients daily
- Topical steroids for acute flares: when not responding to treatment
- Steroid sparing agents
35
What are some examples of steroid sparing agents?
- Topical calcineuin inhibitors: tacrolimus
- Antihistamines (fotr itch)
- 2nd line systemic treatments: azathioprine, MTX
36
What life threatening emergency caused by herpes simplex virus 1 or 2?
- Eczema herpeticum
| - Usually occurs in children with pre-existing eczema
37
What is the management for eczema herpeticum?
- Admit to hospital
| - IV acyclovir
38
What is psoriasis?
- Chronic skin condition which squaly plaques form on the extensor surfaces of the body
- Can affect scalp and nails
39
What are the different types of psoriasis?
- Chronic plaque psoriasis
- Flexure psoriasis
- Scalp
- Guttate
- Palmar-plantar
- Nail
- Generalised pustular
40
What are the features of nail psoriasis?
- Pitting
- Oncholysis
- Thick/hyperkeratotic nails
41
What are some possible triggers of psoriasis?
- Stress
- Alcohol
- Smoking
- Trauma
- Steroid withdrawal
42
Which medications trigger psoriasis?
- Beta blockers
- Lithium
- NSAIDs
- ACEi
- TNF inhibitors
- Anti-malarials
43
What is Koebner phenomenon?
-Psoriasis that spreads to an area of skin that has been broken
ie will move down the track line a scratch
44
How is psoriasis managed?
1. Emollients
2. Topical steroids and vit D analogues ie Dovobet
3. Vit D analogues
4. UV light therapy
5. Traditional systemic therapies ie retinoids, MTX, ciclosporin
6. Biologics ie anti-TNF (infliximab, adalamumab)
45
What other factors need to be considered/looked for with someone who has psoriasis?
- Psoriatic arthritis
| - Adults with psoriasis are at increased risk of CV disease
46
What triggers guttate psoriasis and what is it?
- Triggered by strep throat (strep group A)
- Raindrop shaped plaques
- Silver scale
- Trunk
47
How is guttate psoriasis investigated and treated?
-Throat swab for anti-streptolysin O titre
-RX:
>Most self resolve within 2-3 months
>Topical agents as per psoriasis
>UVB phototherapy
48
What is acne vulgaris?
-Common skin condition affecting adolescents usually affecting the face, neck and trunk
49
What's the pathology behind acne?
-Obstruction of the pilosebacious follicles with keratin plugs causing:
>Comedones
>Inflammation
>Pustules
50
What is the causative organism responsible for acne vulgaris?
-Propionibacterium acnes
51
What are the features of acne vulgaris?
- Comedones: dilated sebaceous follicles (closed top: white heads, open top: blackheads)
- Papules
- Pustules
- Nodules
- Cysts
- Scarring
52
How is acne vulgaris managed?
- Single topical therapy ie topical retinoids or benzylperoxide
- Topical combination ie tetracycline and a stage 1 topical therapy
- Oral antibiotics (oxytetracycline or doxycyline) may need to wait 3-4 months
- Oral isotretinoin
53
What are some side effects of isotretinoin?
- Dry skin
- Depression
- Liver function derangement
- Increase in serum triglyceride
- Teratogenic
- Hair thinning
- Nose bleeds
- IIH
- Photosensitivity
54
What is Wallace's rule of 9s for burns?
- Arm 9%
- Front of leg 9%
- Back of leg 9%
- Front of torso 9%
- Back of torso 9%
- Front of abdomen 9%
- Back of abdomen 9%
- Head and neck 9%
55
What are different gradings for burns?
- Superficial epidermal: red, painful
- Superficial dermal: red, painful, blistered
- Deep dermal: decreased sensation, white
- Full thickness: white, no pain, no blisters, muscle and bone involvement
56
What is the Parkland formula for burns?
-Calculates how much fluid replacement someone needs following a burn
57
What is the calculation for the Parkland formula?
- Fluid requirement (mls) = TSBA burn (%) x body weight (kg) x 4
- over 24 hours
58
What is the management of burns?
- ABCDE
- Stop the burning
- Clingfilm
- Monitor U&Es
- Superficial burns: use emollients
- If circumferential: escharotomy
- Analgesia
- Non-adherent dressing
59
What are the indications for referral to secondary care
- Any burn affecting the face, neck, hands, feet and genitals
- Any deep dermal or full thickness burns
- Smoke inhalation injury
- Chemical or electrical burns
- NAI
60
What are the features of acne roasacea?
- Affects the nose, cheeks and forehead
- Flushing (can be alcohol related)
- Telangiectasia
- Later: develops into persistent erythema with papules and pustules
- Rhinophyma
- Blepharitis, keratitis, conjunctivitis
61
How is acne rosacea managed?
- topical metronidazole
- Systemic antibiotics: oxytetracycline
- high SPF suncream
- Camouflage creams to conceal redness
- Laser treatment for telangectasia
- surgical repair of rhinophyma
62
What is bullous phemigoid?
- An autoimmune condition causing sub-epidermal blistering of the skin
- Causes itchy tense blisters around the flexures
63
Who is commonly affected by bullous phemigoid?
-Elderly patients
64
What does a biopsy of bullous phemigoid contain?
-IgG and C3
65
How is bullous phemigoid managed?
- Refer to dermatology
| - Oral corticosteroids
66
What is vitilgo?
- An autoimmune disease causing a loss of melanocytes = depigmentation
- Commonly presents in 20s-30s
67
Management of vitiligo?
- Sunscreen for affected areas
- Camouflage make up
- Topical corticosteroids
- ?Tacrolimus and phototherapy
68
What diseases are associated with vitiligo?
- T1DM
- Addison's disease
- Pernicious anaemia
- Autoimmune thyroid disease
- Alopecia areata
69
What is alopecial areata?
- An autoimmune cause of localised hair loss
| - Occurs in well demarcated patches
70
Management of alopecia areata?
- Usually regrows back itself
- Education
- Topical steroids
- Topical minoxidil (restores blood supply to area)
- Phototherapy
- Contact immunotherapy
- Wigs
71
What is erythema nodosum?
-Inflammation of the subcutaneous fat
72
What are the features of erythema nodosum?
- Tender
- Erythematous
- Nodular lesions
- Usually over the shins
73
What are the causes of erythema nodosum?
- Infection ie TB, strep
- Systemic disease ie IBD, sarcoidosis, Bechets
- Malignancy ie lymphoma
- Pregnancy
- Drugs ie penicillin, cocp, sulphonamides
74
How is erythema nodosum managed?
- Usually self resolves within 6 weeks
- Lesions heal without scarring
- Treat pain with analgesia
75
What is pellagra?
- A disease caused by deficiency of nicotinic acid (Vit B3)
- Common in alcoholics
- Can occur as consequence of isoniazid therapy
76
What are the features of pellagra?
```
-4 Ds
>Diarrhoea
>Dementia/depression
>Dermatitis - brown and scaly skin on sun exposed areas
>Death (if not treated)
```
77
How is pellagra managed?
-Vitamin B3 supplementation
78
What is keratocanthoma?
-Benign epithelial tumour filled with keratin
>looks like a volcano/crater
>SCC needs to be excluded
79
How are keratocanthomas managed?
-Usually regress within 3 months. (often scars)
-Should be excised
>5% progress to SCC
80
What is seborrhoeic dermatitis?
-Chronic inflammation reaction to a normal skin inhabitant - Malassezia furfur
81
What are some associations with seborrhoeic dermatitis?
- HIV
| - Parkinson's disease
82
Which parts of the body does seborrhoeic dermatitis affect?
- Scalp
- Periorbital
- Auricular
- Nasolabial folds
- Cheeks
83
How is face and body seborrhoeic dermatitis managed?
- Topical antifungals ie ketoconazole
| - Topical steroids (for short term use for acute flares)
84
How is scalp seborrhoeic dermatitis treated?
- Head and shoulders shampoo (contains zinc pyrithione)
- 2nd line: ketoconazole
- Selenium as topical steroid
85
What are seborrhoiec keratoses?
-Seborrhoeic warts
>benign, epidermal lesions
-Commonly affects older people
86
What are the features of seborrhoiec keratosis?
- Vary in colour: pink fleshy, light brown, dark brown, black
- 'Stuck on' appearance
- Keratotic plugs on surface
87
Management of seborrhoeic keratoses?
- Reassure as benign
| - Removal if irritating: curettage, cryosurgery
88
What is actinic keratosis?
-Premalignant condition associated with chronic skin exposure
89
What is the spectrum of disease associated with actinic keratosis?
1. Photodamage
2. Actinic keratosis
3. SCC in situ (Bowen's disease)
4. Invasive SCC
90
What are the features of actinic keratosis?
- Small crusty lesions
- Pink, red, brown or skin colour
- Typically on skin exposed areas
- Multiple lesions can be present
91
How are actinic keratoses managed?
- Reduce further risk with sun avoidance/sunscreen
- Flurouracil cream
- Topical diclofenac
- Cyrotherapy
- Curretage and cautery
92
What is erythema abigne?
-Rash caused by heat exposure
ie old lady using hot water bottle to treat back pain for hours
-Risk factor for SSC
-Needs to treat the reason why they are using the heat ie the back pain
93
What is acanthosis nigricans?
-Brown/black poorly defined velvety hyperpigmentation
-Found in the body folds
>neck
>axilla
>groin
>umbilicus
>forehead
94
What conditions are associated with acanthosis nigricans?
-Insulin resistance
-Paraneoplastic
>pancreatic and gastric malignancies
>involvement of mucous membranes suggests malignancy
95
What are the features of pyoderma gangrenosum?
- A lesion which initially starts as a small red papule and later develops into a deep red necrotic ulcer with a purple border
- Typically affects lower limbs
96
What causes pyoderma gangrenosum?
- 50% idiopathic
- IBD
- Connective tissue disorders: RA, SLE
- Myeloproliferative disorders
- Lymphoma, myeloid leukaemia
- Monoclonal gammopathy
- Primary billiary cirrhosis
97
How is pyoderma gangrenosum treated?
- Oral steroids
| - If not responsive: ciclosporin, infliximab
98
What are features of lichen sclerosus?
- An inflammatory condition affecting the vulva
- White plaques caused by atrophy of the epidermis and itch
- Biopsy is diagnostic
99
How is lichen sclerosus managed?
- Topical steroids
- Emollients
- Careful follow up due it increased risk of vulval cancer
100
What are the features of lichen planus?
-All the Ps:
>Purple
>Pruritic
>Papular
>Polygonal
-Most common on palms, soles and genitals
-White lace pattern on the surface 'Wickham's striae'
-Nail signs: thinning of nail plate, longitudinal ridging
101
What are some causes of lichenoid drug eruptions?
- Gold
- Quinine
- Thiazides
102
How is lichen planus managed?
- Topical steroids
- Oral disease: benzylamine mouthwash
- Oral steroids/Immune suppression for extensive disease
103
What is molluscum contagiosum?
-Raised papules caused by molluscum contagiosum virus
104
What is molluscum transmitted?
- Close personal contact
| - Contaminated surfaces such as shared towels and flannels
105
What are features of molluscum?
- Pinkish/pearly white papules
- Central umbilication
- Up to 5mm diameter
- Lesions appear in clusters
- Spares palms and soles
- Children: trunk and flexures
- Adults: sexual contact can lead to lesions on the genitalia, pubis, thighs, lower abdomen
106
Self care advice for molluscum?
- Advise patients this is a self limiting condition, lasts <18 months
- Contagious towel sharing
- Don't scratch
107
What are treatment options for molluscum?
- Squeeze after a bath
- Cyrotherapy
- Steroids if itchy
- Antibiotics if crusted/infective looking
108
When should someone with molluscum be referred for specialist input?
- HIV positive
- Eyelid/ocular margin lesions
- Anogenital lesions: refer to GUM
109
What is scabies?
- A sarcopetes scabeii bite
- Commonly affects children and young adults (shared houses)
- Eggs laid in stratum corneum
110
What are the features of scabies?
- Widespread pruritus
- Linear burrows (side of fingers, web spaces, flex of wrist
- Excoriations
- Infants: face and scalp
- Complicated in immunosuppressed: crusted scabies
111
How long will the pruritus from scabies persist for following successful treatment?
-4-6 weeks
112
How is scabies treated?
- Permethrin 5%
- Ensure whole household treated
- Clean all clothes, bedding, towels etc on 1st day of treatment
113
WHat is hyperhidrosis?
-Excesive sweating
114
How is hyperhidrosis managed?
- Topical aluminium chloride
- Electric current: iontophoresis
- Botox of axilla
- Surgery
115
What is hereditary haemorrhagic telengectasia?
-An autosomal dominant condition characterised by multiple telangiectasia over the skin and mucus membranes
116
What are the diagnostic criteria for hereditary haemorrhagic telengiectasia?
1. Epistaxis: Spon. nose bleeds for >3/7
2. Telangiectasia: Multiple at lips, oral cavity, fingers, nose
3. Visceral lesions: Gi telangiectasia (on colonscopy), Atriovenous malformations - pulmonary, hepatic, cerebral, spinal
4. Family history
117
What are the features of pityriasis rosea?
- Acute self-limiting rash (resolves after 4-12 weeks)
- Young adults
- Associated with HHV-7
- Herald patch (early lesion) - appears on trunk
- Followed by erythematous oval scaly patches
- URTI prodrome
118
What skin condition is a medical emergency?
-Erythroderma!
| >when >95% of skin is involved in a rash of any kind
119
What are some causes of erythroderma?
- Idiopathic
- Eczema
- Psoriasis
- Lymphoma
- Leukaemia
- Drugs: Gold
120
What are features of erythroderma?
- Dry mucous membranes
- Pain/discomfort
- Hypothermia
- Electrolyte imbalances
121
What parameters need monitoring for a pt with erythroderma?
- Dehydration
- Infection
- High output cardiac failure (SOB)
- Hypothermia
122
How is erythromderma managed?
- Admit to hospital urgently
- IV fluids
- Analgesia
- Emollients
- Cool wet dressings
- Bed rest in warm room
- Nutritional support
