Module 2A - Dermatology Flashcards
1
Q
Which cells predominantly make up the epidermis?
A
Keratinocytes –> migrate from lower epidermis (stratum basale)
- Once they reach the upper epidermis, they lose their nuclei and form tightly packed layers of keratin to form the stratum corneum
2
Q
What is the top outer layer of the skin called –> what is it’s function
A
Epidermis –> barrier function
3
Q
vicious cycle in eczema
A
4
Q
Atopic eczema –> where does it usually affect + management
A
- Flexor surfaces
Management: - emollients –> regular use
- topical steroids –> acute flares
- phototherapy –> UVB
- DMARDs
- (if itchy –> antihistamines)
5
Q
Emollients
A
6
Q
Steroids and examples of use
A
- lower potentency for delicate areas such as face or genitals –> hydrocortisone 1%
- higher potency may be required for thicker skin areas like palm or soles –> betamethasone valerate 0.1%
7
Q
Fingertip unit (FTU)
A
- 1 fingertip unit (FTU) covers area size of 2 hands
8
Q
scoring tools –> EASI and DLQI –> what condition they used in
A
atopic eczema
9
Q
What type of hypersensitivity reaction is allergic contact dermatitis?
A
Type IV delayed hypersensitivity reaction
–> reactions tend to happen 48-72hrs after contact with the allergen
10
Q
A
Contact dermatitis
11
Q
Why would patch testing be used?
A
If unknown allergen/trigger of contact dermatitis
12
Q
Contact dermatitis –> management
A
- Avoid contact with allergen!
- Liberal emollients
- Topical steroids
- Treat any secondary infection
13
Q
Skin anatomy –> label
A
14
Q
time frame
Acute vs chronic urticaria
A
- Acute –> < 6 weeks
- Chronic –> > 6 weeks
15
Q
Urticaria pathophysiology:
____ ____ degranulation
- type of hypersensitivity reaction
A
Mast cell
- Type I hypersensitivity immediate reaction due to allergen –> IgE mediated
16
Q
4 types of hypersensitivity reactions
A
Type I –> reaction mediated by IgE antibodies
Type II –> cytotoxic reaction mediated by IgG or IgM antibodies
Type III –> reaction mediated by immune complexes
Type IV –> delayed reaction mediated by cellular response (48-72hrs)
17
Q
All atopic diseases are what type of hypersensitivity reaction?
A
Type I –> IgE mediated immune repsonses
18
Q
what to avoid + medications
Urticaria management
A
- Avoid trigger/allergen +/- treat infection + Avoid NSAIDs, aspirin, codeine
- 2nd-gen H1 antihistamine (non-sedating) up to QDS –> cetirizine, loratadine
- Sedating histamine at night –> eg. chlorphenamine
- Next step is prednisolone 30mg –> 5-6 days
19
Q
Test for type I hypersensitivity
A
Skin prick testing
20
Q
- Nodule
- Papule
- Pustule
- Vesicle
- Papule
A
- Nodule = larger
- Papule = smaller
- Pustule = blob has pus in it
- Vesicle = blob with fluid inside (clear)
- Papule = blob of skin with nothing inside it
21
Q
Herpes simplex pathogens
A
- HSV-1 –> orofacial (80-90%)
- HSV-2 –> genital (70-90%)
22
Q
Herpes simplex management
A
- Topical acyclovir 5% ointment
- If systemic –> acyclovir 200mg x5 a day for 5 days
- Prophylaxis –> acyclovir 200mg TDS for 6-12 months
23
Q
Herpes zoster pathogen + aetiology
A
- Varicella zoster virus (VZV)
- reactivation of latent VZV in a sensory ganglia
24
Q
Treatment for any herpes virus
Herpes zoster –> treatment
A
- Acyclovir
- can also give analgesia to relieve pain
25
# treatment?
Viral warts pathogen
human papillomavirus (HPV)
--> benign condition no treatment
26
Molluscusm contagiosum pathogen
Molluscum contagiosum virus (MCV) --> poxvirus
27
Impetigo common pathogens
Staph. aureus and Strep. pyogenes
28
Impetigo --> treatment
1. Clean --> hydrogen peroxide 1%
2. Topical antibx --> fusidic acid
29
Folliculitis pathogens
Staph. aureus, Pseudomonas aeruginosa
30
2 bacteria that are infrequent resident flora of the skin
Staph. aureus and Strep. pyogenes
31
Cellulitis pathogens
Staph. aureus and Strep. pyogenes
32
Cellulitis --> treatment
beta-lactams --> penicillins and cephalosporins
33
Necrotising fascitis --> treatment
- surgical debridement, or amputation
- antibiotics --> gentamicin, clindamycin
34
Scabies pathogen
Sarcoptes scabiei var. hominis (human itch mite)
35
Scabies management
Skin lotions containing permethrin --> all family have to take
36
Tinea --> common organisms
- Tinea verrucosum
- Tinea rubrum
- Micosporum canis
37
Tinea treatment
topical antifungals --> imidazoles
38
Tinea...
- corporis
- capitis
- pedis
- cruris
- Tinea Corporis --> body
- Tine Capitis --> head (note: can get ringworm scab thing on scalp)
- Tinea Pedis --> feet
- Tinea Cruris --> groin
39
Candida intertrigo pathogen
Yeast --> usually candida albicans
40
Candida... treatment
topical antifungals
41
Pityriasis Versicolor and Seborrhoeic dermatitis pathogen
Yeast --> Malassezia furfur
42
Pityriasis versicolor treatment
- selenium sulphide shampoo (2.5%)
- ketoconazole shampoo
- or topical antifungals
43
A - HSV infection
B - Molluscum contagiosum
C - Folliculitis
D - Mucocutaneous leishmaniasis
44
A - HSV infection
B - Impetigo
C - Erysipelas/Cellulitis
D - Cutaneous leishmaniasis
45
# IgE-mediated, Non-IgE-mediated, Non-allergic food hypersensitivity
Place into categories
- milk, egg, and peanut allergy
- Coeliac disease (gluten)
- Pollen related allergy
- lactose intolerance
- IgE-mediated --> milk, egg, and peanut allergy + pollen related allergy
- Non-IgE-mediated --> Coeliac disease (gluten)
- Non-allergic food hypersensitivty (food intolerance) --> Lactos (milk) intolerance
46
Which T-helper cell is involved in IgE production, mast cell activation, and allergic disease?
Th-2
47
# guttate psoriasis?
Psoriasis --> Management
- Vitamin D3 analogues --> calcipotriol
- Corticosteroids --> topical or oral
- Coal tar --> soothes
- Keratolytics (eg. salicylic acid) --> reduces scales --> enhances penetration of topical treatment
- Phototherapy --> UVB, PUVA --> narrow-band UVB is best
- Topical dithranol --> good for inflammation and over production of skin cells
- Biologics --> anti-TNFs
(Guttate psoriasis --> often spontaneously resolves within 2/3 months)
48
UVA vs UVB
- UVA --> causes ageing
- UVB --> main carcinogen --> damages DNA and inhibits DNA repair processes
49
Breslow thickness
- Breslow thickness --> predicts melanoma survival (5 yr survival)
- essentially how deep the cancer goes
50
Glasgow 7-point checklist for melanoma
51
Management of any suspected skin cancer
- Skin excision biopsy --> histopathology
52
Exclamation mark hair --> what condition
Alopecia areata
53
Alopecia Totalis vs Alopecia Universalis
- Alopecia Totalis --> total loss of scalp hair
- Alopecia Universalis --> total loss of body hair
54
Trichotillomania
Self-induced pulling of hair
55
Hirsutism --> what is it + if symptoms of deep voice, increased muscle bulk, or clitoromegaly, then what are your next steps
- Androgen-dependent hair growth in a female
- urgently referred to endocrine for possible ovarian or adrenal tumour --> can also check for abdominal mass
56
Nail problems:
- Clubbing -->
- Koilonychia -->
- Onycholysis -->
- Pitting -->
57
Management of nail psoriasis
- Potent topical steroid at base of nail/cuticle
- Steroid injection into base of nail
58
Hutchinson's sign --> what condition?
Extension of pigmentation to nail fold --> acral lentiginous melanoma
59
60
# size?
Papule vs pustule
- Papules = measuring <5mm in diameter
- Pustules = pus-filled spots
61
# size?
Nodulocystic acne --> more severe
Nodules = inflamed, swollen lesions >5mm
62
2 skin changes seen in acne
63
Grading of severity of acne
64
Acne management
- Benzoyl peroxide (gel or face wash) --> antiseptic --> reduces no. bacteria on skin
- Topical retinoids (gel or cream) --> eg. tretinoin, adapalene --> works by keratinocyte proliferation --> removes dead skin cells from surface of skin (exfoliating) --> prevents building up within hair follicles
- Topical antibiotics --> eg. erythromycin, doxy, clarithro
- Combined oral contraceptive pill for females --> lowers androgen lvls --> less sebum and less severe acne
- +/- Oral antibiotics (doxy, erytrho, clarithro)
- Isotretinoin --> severe acne (specialist use)
65
Acne --> when to refer to dermatology
66
What pill that women sometimes take can make acne worse?
Progesterone only pills --> the lack of oestrogen may allow for higher lvls of androgen
67
Diagnostic features of rosacea
68
Rosacea management
- 1st line --> topical ivermectin and oral doxycycline
69
Pathogenesis of acne
- Keratinocyte proliferation - leading to follicular plugs
- Androgen-induced sebum production - usually occurs during puberty
70
Most common side effect of topical steroids
Skin thinning
71
Creams vs ointments
- Ointments are oil-based
- Creams are a mixture of oil and water
72
How long should you wait between emollient application and topical steroids application
30 mins
73
74
Name 3 pre-cancerous lesions and treatment for each
- Actinic keratoses, Bowen's disease (SCC in situ), and lentigo maligna are all pre-cancerous lesions
- Actinic keratoses + Bowen's --> Efudix cream or 5-fluorouracil (topical chemo.) + cryotherapy
(Curettage and cautery (C+C) can be used for Bowen's)
- Lentigo maligna --> imiquimod (immunosuppessive drug) or surgical excision
75
Risk factors associated with skin cancer
76
77
# + treatment
Erythema nodosum causes
- depends on cause --> eg. stopping causative drug, symptomatic treatment
- if no cause --> bed rest + fluids
78
Treatment of pyoderma gangrenosum
High-dose oral steroids
79
- Necrobiosis lipoidica --> associated with diabetes
80
- annular granuloma --> raised borders
- associated with autoimmune and diabetes
- usually self-limiting
81
# most common trigger
- Erythema mulitforme - target lesions
- most common triggers - infections (Herpes simplex)
82
Treatment of a widespread erythematous rash
Moisturiser + topical steroid
83
- Fluid-filled blisters, erythematous patches
--> Bullous pemphigoid
- Skin biopsy
- Management --> high dose oral prednisolone is mainstay, then can add potent topical steroids, azathioprine
84
- erythematous ulcerated patches from ruptured blisters
- pemphigus vulgaris
- skin biopsy
- potent topical steroids, high dose oral prednisolone, azathioprine
85
- Dermatitis herpetiformis
- Check TTG (tissue transglutaminase) --> coeliac blood test
- Skin biopsy --> IgA deposition
- Management --> gluten-free diet and topical steroids
- Dapcin if coeliac diet doesn’t work
86
Causes + investigations + management
87
Wound healing video
Dr Matt and Dr Mike video:
https://www.youtube.com/watch?v=1VBLmyDjC0w
88
Vitiligo is associated with...
Autoimmune diseases --> Addison's, Type 1 diabetes
89
Serious condition that eczema can develop into --> pt has red, rash, and outbreak of spots/inflammation + management
- Eczema herpeticum
- IV antivirals (aciclovir)
90
Acne vulgaris drugs that are contraindicated in pregnancy
Tetracyclines and retinoids --> teratogenic
91
Sebhorroeic dermatitis treatment
- Corticosteroids
- Scalp --> ketaconazole shampoo
- Face/body --> topical antifungal (ketoconazole)
92
Pityriasis rosea often follows a...
Viral infection
93
Drugs known to exacerbate psoriasis
- Lithium
- Anti-malarials
- Beta-blockers
- ACEi
- anti-TNF-alpha
- NSAIDs
94
TEN (toxic epidermal necrolysis) --> 4 classes of drugs that can cause crossreactions leading to TENs
- Beta-lactam antibiotics --> penicillin, cephalosporin and carbapenem (penicillins --> co-amoxiclav)
- Sulph- drugs
- Anticonvulsants --> carbamazepine, phenytoin
- NSAIDs
95
SJS vs TEN
- SJS --> < 10% of body affected by rash
- TEN --> > 30% of body affected by rash
(overlap in between)
96
A 62-year-old female is referred to dermatology by her GP due to a lesion over her shin. It initially started as a small red papule which later became a deep, red, necrotic ulcer with a violaceous border. What is the likely diagnosis?
Pyoderma gangrenosum
97
Shingles (herpes zoster) --> treatment + timeline to start treatment within
Oral antivirals --> within 72hrs onset
98
Vitamin D (Calcitriol) --> functions + how is it acquired
- Important for bones --> increases dietary calcium and phosphate absorption
- Acquired from UV skin exposure (up to 15 mins per day) and Diet
- Vitamin D deficiency common --> it is important to give people advice about sun protection but also advise vit D supplements
99
Why are transplant patients at an increased risk of skin cancer?
- due to immunosuppression
100
What are the two main types of albinism?
Oculocutaneous albinism:
- Type 1: more severe - no melanin
- Type 2: some melanin
- Ocular albinism: normal, or slightly paler than normal eyes for their ethnicity, skin, and hair
101
Actinic keratoses --> pathology + aetiology + location on body
- Proliferation of cytologically aberrant epidermal keratinocytes
- UV-induced + very common in bald white men over 75yrs
- Sun-exposed areas --> scalp
102
BCC --> pathogenesis + mutations in what gene predispose to BCC
- Basal Cell Carcinoma (aka. rodent ulcer) is the most common cancer in humans, derived from non-keratinising cells originating in the basal layer of the epidermis
- mutations in the PTCH gene
103
Erythema migrans --> what disease + management
- Lyme disease
- Antibiotics (doxy, amox)
104
Impetigo --> most common causative pathogen + management
- Staph. A or Strep. pyogenes
1. Clean --> hydrogen peroxide 1% cream
2. Topical antibiotics --> fusidic acid
105
Gorlin's syndrome predisposes to what skin cancer?
BCC
106
Alopecia ariata management
- 80-90% will spontaneously regrow
- consider --> topical corticosteroids, topical minoxidil
107
Dermatitis herpetiformis --> underlying pathophysiological process + skin biopsy finding
Formation of IgA antibodies --> skin biopsy shows a granular pattern of IgA deposition
108
Impetigo vs Measles --> isolation periods
- Impetigo --> isolate until 48hrs after starting treatment (fusidic acid) and should have crusted over
- Measles --> isolate for 4 days after rash appears
109
Most common side effect of oral isotretinoin
Dry skin
110
What drug type is known to exacerbate plaque psoriasis?
Beta-blockers
111
What gene is associated with eczema?
Filaggrin gene
112
Biopsy and immunofluorescence showing IgG auto-antibody deposits within the epidermis
VS
Biopsy and immunofluorescence would show IgG auto-antibodies deposited on the basement membrane
- Pemphigus vulgaris vs bullous pemphigoid
- Pemphigus --> deposits within epidermis
- Bullous pemphigoid --> deposits on basement membrane
113
Nikolsky sign positive suggests
Pemphigus Vulgaris
114
Psoriasis --> which drug may be used long term
Calcipotriol (vit D3 analogue)
--> reduces epidermal proliferation, reduces scale and thickness of plaques, but doesn't help with erythema
115
