Passmed Dermatology Mushkies Flashcards
1
Q
What is a common and benign condition characterised by the development of a painful nodule on the ear?
A
Chondrodermatitis nodularis helicis (CNH)
2
Q
What are some things that cause chondrodermatitis nodularis helicis (CNH)?
A
- Persistent pressure on ear
- Trauma
- Cold
3
Q
How does one manage chondrodermatitis nodularis helicis?
A
- Reducing pressure on ear (foam ear protectors)
- Cryotherapy/steroid injection/collagen injection
- Surgical Rx, but high recurrence rate
4
Q
What does CNH stand for?
A
Chondrodermatitis nodularis helicis
5
Q
What are some differential diagnoses for shin lesions?
A
- Erythema nodosum
- Pyoderma gangrenosum
- Pretibial myxoedema
- Necrobiosis lipoidica diabeticorum
6
Q
How does one describe erythema nodosum?
A
Symmetrical, erythematous, tender nodules which heal without scarring
7
Q
What are the most common causes of erythema nodosum?
A
- NO = idiopathic
- Drugs = penicillin/sulphonamides
- OCP/Pregnancy
- Sarcoidosis/TB
- UC/CD/Behcets
- Micro = Streptococcus, mycoplasma, EBV
- Malignancy/lymphoma
8
Q
What are 3 drugs that can cause erythema nodosum?
A
- Penicillins
- Sulphonamides
- OCP
9
Q
How does one describe pretibial myxoedema?
A
Symmetrical, erythematous lesions seen in Graves disease
10
Q
What are the SBA buzzwords for pretibial myxoedema?
A
Shiny, orange peel skin
11
Q
How does one describe pyoderma gangrenosum?
A
A small red papule that develops into deep, red, necrotic ulcers with a violaceous border
12
Q
What are some causes of pyoderma gangrenosum?
A
- Idiopathic = 50%
- IBD
- CTD
- Myeloproliferative disorders
13
Q
How does one describe necrobiosis lipoidica diabeticorum?
A
Shiny, painless areas of yellow/red skin typically on the shin of diabetics
14
Q
What other dermatological finding is necrobiosis lipoidica diabeticorum often associated with?
A
Telangectasia
15
Q
Where is venous ulceration most typically seen?
A
Above the medial malleolus
16
Q
What is the most important investigation for venous ulceration?
A
ABPI
17
Q
What is the normal range for ABPI?
A
0.9-1.2
18
Q
What ABPI value typically indicated arterial disease?
A
<0.9
19
Q
When might you find a pt with arterial disease with ABPI >1.2?
A
False negative results secondary to arterial calcification e.g. in diabetics
20
Q
What is the management of venous ulcers?
A
- Compression bandage, usually four layer
- Oral pentoxifylline, a peripheral vasodilator, improves healing rate
- Flavinoids (small evidence base)
21
Q
What is the only treatment shown to be of real benefit for rx of venous ulcers?
A
Compression bandaging
22
Q
How can one remember the site of ulceration for venous and arterial ulcers?
A
- vEnous = mEdial
2. Arterial = lAteral
23
Q
What are risk factors for SCC of the skin?
A
- Sunlight exposure
- Actinic keratoses and Bowen’s disease
- Immunosuppression
- Smoking
- Long standing ulcers e.g. Marjolin ulcers
- Genetic
24
Q
What are 2 genetic conditions that predispose to SCC of skin?
A
- Xeroderma pigmentosum
2. Oculocutaneous albinism
25
What should the surgical excision margin be for SCCs that are <20mm in diameter?
4mm
26
What should the surgical excision margin be for SCCs that are >20mm in diameter?
6mm
27
What do you call stress ulcers in burns patients?
Curlings ulcers
28
What is a common result of Curlings ulcers?
Haematemesis
29
What is a Curling's ulcer?
Acute gastric erosion from severe burns as reduced plasma volume leads to ischaemia and cell necrosis of gastric mucosa
30
What is a Dieulafoy lesion?
Large, single, tortuous arteriole in stomach submucosa that erodes and bleeds, but can also present anywhere in GI tract.
31
How do you manage burns causes by heat?
1. Remove person from source
2. Irrigate with cool (not iced) water for 10-30 mins
3. Cover burn using cling film
32
How do you manage electrical burns?
Switch off power supply, remove person from the source
33
How do you manage chemical burns?
Brush off any powder, irrigate with water
34
What are 3 ways you can assess the extent of a burn?
1. Wallace's rule of Nines
2. Lund and Browder chart
3. Palmar surface area method
35
What is Wallace's rule of Nines for burns?
1. Head + Neck = 9%
2. Arm = 9%
3. Anterior leg = 9%
4. Posterior leg = 9%
5. Anterior chest = 9%
6. Posterior chest = 9%
7. Anterior abdomen = 9%
8. Posterior abdomen = 8%
9. Yeah kan do
36
What is the most accurate method for assessing the extent of a burn?
Lund and Browder chart
37
What is the Palmar surface area method for assessing burns?
1. Palmar surface = roughly 1% of TBSA
| 2. Not accurate for burns >15% TBSA
38
What is the histology and appearance of a 1st degree burn?
1. Superficial epidermal
| 2. Red and painful
39
What is the histology and appearance of a 2nd degree burn?
1. Superficial dermal /deep dermal (partial thickness)
| 2. Pale pink, painful, blistered/white and reduced sensation
40
What is the histology and appearance of a 3rd degree burn?
1. Full thickness
| 2. White/brown/black, no blisters, no pain
41
When are IV fluids indicated for burns?
1. >10% TBSA in children
| 2. >15% TBSA 2nd/3rd degree burns in adults
42
What is the formula used for fluid given in burns pts?
Parkland formula
43
What is the Parkland formula?
Volume of fluid = TBSA x weight in kg x 4
44
How much of the calculated fluid requirement in a burns pt should be given in the first 8 hours?
Half
45
What do you call the tough leathery tissue remaining after a full-thickness burn?
Eschar
46
What is an escharotomy?
Surgical procedure used to treat full-thickness (3rd degree) burns
47
What is the rationale behind an escharotomy?
Following a full-thickness burn, as the underlying tissues are rehydrated, they become constricted due to the eschar's loss of elasticity, leading to impaired circulation distal to the wound. An escharotomy can be performed as a prophylactic measure as well as to release pressure, facilitate circulation and combat burn-induced compartment syndrome
48
When is an escharotomy typically used?
1. Circumferential burns affecting a limb
| 2. Severe torso burns impeding respiration
49
Is there any evidence to support the use of Abx prophylaxis/topical Abx in burns pts?
No
50
What is a Marjolin's ulcer
An aggressive ulcerating SCC presenting in an area of previously traumatised, chronically inflamed, or scarred skin
51
What is a midline swelling lined by squamous epithelium and hair follicles likely to be?
Dermoid cysts
52
Why are dermoid cysts typically located in the midline?
They are embryological remnants
53
What kind of tumour is also referred to as aggressive fibromatosis?
Desmoid tumour
54
Where do desmoid tumours typically arise?
In ligaments and tendons
55
What is the most common form of skin cancer?
BCC
56
Where do BCCs typically occur?
Sun exposed sites apart from the ear
57
What are 4 subtypes of BCCs?
1. Nodular
2. Morphoeic
3. Superficial
4. Pigmented
58
What is the growth of BCCs like?
Typically slow growing with low metastatic potential
59
What is the management of a BCC?
Surgical excision, topical chemotherapy and radiotherapy are all successful
60
What is the treatment of choice for SCCs?
Wide local excision
61
How can one classify the main diagnostic features for malignant melanoma?
1. Major criteria
| 2. Minor criteria (secondary features)
62
What are the major criteria for diagnosis of malignant melanoma?
1. Change in size
2. Change in shape
3. Change in colour
63
What are the minor criteria for diagnosis of malignant melanoma?
1. Diameter >6mm
2. Inflammation
3. Oozing/bleeding
4. Altered sensation
64
How should one manage lesions that are suspicious and may be a malignant melanoma?
Excision biopsy, followed by further re-excision of margins once diagnosis is confirmed by pathology report
65
What are the margins of excision of a malignant melanoma, with regards to Breslow thickness?
1. 0-1mm = 1cm
2. 1-2mm = 1-2cm
3. 2-4mm = 2-3cm
4. >4mm = 3cm
66
What is Kaposi's sarcoma?
A tumour of vascular and lymphatic endothelium, associated with immunosuppression from e.g. HIV
67
What does Kaposi's sarcoma look like?
Purple cutaneous nodules
68
What is dermatitis herpetiformis?
Autoimmune blistering skin disorder, associated with Coeliac disease
69
What is a dermatofibroma?
A benign lesion consisting of histiocytes, blood vessels and fibrotic changes
70
How do dermatofibromas present?
Firm elevated nodules, usually with a history of trauma
71
What are pyogenic granulomas?
Red nodules that are a overgrowth of blood vessels, that usually follow trauma
72
What other skin lesion do pyogenic granulomas mimic?
Amelanotic melanomas
73
What is acanthosis nigricans?
Brown to black, poorly defined, velvety hyperpigmentation of the skin
74
Where is acanthosis nigricans typically found?
In body folds
75
What is the most common cause of acanthosis nigricans?
Insulin resistance
76
What is the pathophysiology of acanthosis nigricans?
Insulin resistance --> raised circulating insulin levels --> insulin spillover into skin --> hyperplasia of skin
77
What do you call acanthosis nigricans in the context of a malignant disease?
Acanthosis nigricans maligna, is a paraneoplastic syndrome
78
What complication are electrical high voltage burns associated with and thus what is the treatment?
Rhabdomyloysis --> ATN --> Aggressive IV fluids
79
What virus causes molluscum contagiosum?
MCV
80
What family of viruses is molluscum contagiosum found in?
Poxviridae
81
How is molluscum transmitted?
1. Directly = close personal contact
| 2. Indirectly = fomites e.g. shared towels
82
In what population do the majority of cases of molluscum occur?
In children (often with atopic eczema), max. incidence in preschool children aged 1-4 years
83
How can one describe molluscum?
Pinkish/pearly white papules with a central umbilication, up to 5mm in diameter
84
Where on the body does molluscum not appear?
Palms of hands and soles of feet
85
In children, where are molluscum lesions commonly seen?
Trunk and flexures, but anogenital lesions can also occur
86
How can one manage molluscum?
1. Self care measures
| 2. Treatment measures
87
What are some self care measures for molluscum?
1. Reassure it is self-limiting
2. Spontaneous resolution within 18m
3. Avoid sharing towels
4. Dont scratch
5. Exclusion from school/swimming/gym is not required
88
What are some treatments for molluscum?
1. Cryotherapy
| 2. Squeezing/piercing
89
When should molluscum be referred?
1. HIV-positive
2. Eyelid-margin/ocular lesions
3. Adults with anogenital --> GUM for other STI screening
90
What is used to treat pityriasis versicolor?
Ketoconazole shampoo
91
What is pityriasis versicolor?
A superficial cutaneous fungal infection caused by Malassezia furfur
92
What does pityriasis versicolor look like?
Hypopigmented/pink/brown, may be more obvious following a suntan, scale is common, mild pruritis
93
Where does pityriasis versicolor typically occur?
Trunk
94
What is the pathophysiology of dermatitis herpetiformis?
Deposition of IgA in the dermis
95
What are the features of dermatitis herpetiformis?
Itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)
96
How does one diagnose dermatitis herpetiformis?
Skin biopsy
97
What does one see on skin biopsy of dermatitis herpetiformis?
Direct immunofluorescense shows deposition of IgA in a granular pattern in the upper dermis
98
What is the management of dermatitis herpetiformis?
1. Gluten-free diet
| 2. Dapson
99
What is pityriasis rosea?
An acute, self-limiting rash which tends to affect young adults
100
What is the aetiology of pityriasis rosea?
Not fully understood, herpes hominis virus 7 (HHV-7) may play a role
101
What are the features of pityriasis rosea?
1. Recent viral infection
2. Herald patch on trunk
3. Followed 1-2 weeks later by erythematous, oval, scaly patches which follow a characteristic distribution with the longitudinal diameters of the oval lesions running parallel to Langer's lines
102
What condition has a 'fir-tree' distribution?
Pityriasis rosea
103
What is the management of pityriasis rosea?
Self-limiting, usually disappears after 6-12 weeks
104
What is the main differential to consider for pityriasis rosea?
Guttate psoriasis
105
What are the features of guttate psoriasis?
1. Strep sore throat 2-4 weeks earlier
| 2. Tear-drop scaly papules on trunk and limbs
106
What is the management of guttate psoriasis?
1. Most resolve spontaneously within 2-3m
2. Topical agents as per psoriasis
3. UVB phototherapy
4. Tonsillectomy may be necessary with recurrent episodes
107
What is the gold standard for management of morphoeic BCC?
Mohs micrographic surgery
108
What are some topical chemotherapies that can be used for treatment of BCC?
Imiquimod, Fluorouracil
109
What are some factors that may exacerbate psoriasis?
1. Trauma
2. Alcohol
3. Steroid withdrawal
4. Drugs
110
What drugs can exacerbate psoriasis?
1. BBs
2. Lithium
3. Antimalarials
4. NSAIDs
5. ACEi
6. Infliximab
111
What can be used for the treatment of mild actinic keratoses?
Topical diclofenac
112
What are actinic/solar keratoses?
A common premalignant skin lesion that develops as a consequence of chronic sun exposure
113
What are features of actinic keratoses?
1. Small, crusty/scaly lesions
2. May be pink/red/brown/skin colour
3. Typically on sun-exposed areas
4. Multiple lesions may be present
114
What are the management options for actinic keratoses?
1. Sun avoidance and sun cream
2. FU cream (2-3wk course)
3. Topical diclofenac (if mild)
4. Topical imiquimod
5. Curettage and cautery
6. Cryotherapy
115
When can a child with impetigo return to school?
When they are no longer contagious =
1. When all lesions have crusted over
2. 48hr after treatment starts
116
What is impetigo?
A superficial bacterial skin infection usually caused by either S. aureus or S. pyogenes
117
How is impetigo transmitted?
1. Direct contact with discharges from the scabs of an infected person
2. Indirect via toys, clothing, equipment and environment
118
What are the key features of impetigo?
Golden, crusted skin lesions typically found around the mouth
119
How can you classify management of impetigo?
1. Limited, localised disease
| 2. Extensive disease
120
What is the management of limited, localised impetigo?
1. Topical fusidic acid first line
2. Topical retapamulin second line
3. Topical mupirocin if MRSA
121
What is the management of extensive impetigo?
1. Oral flucloxacillin
| 2. Oral erythromycin if penicillin-allergic
122
What is acne vulgaris?
1. A common skin disorder which usually occurs in adolescence
2. Typically affects the face, neck and upper trunk
3. Is characterised by the obstruction of pilosebaceous follicles with keratin plugs which results in comedones, inflammation and pustules
123
How can you classify acne?
Mild, moderate and severe
124
What is mild acne?
Open and closed comedones with or without sparse inflammatory lesions
125
What is moderate acne?
Widespread non-inflammatory lesions and numerous papules and pustules
126
What is severe acne?
Extensive inflammatory lesions, which may include nodules, pitting and scarring
127
What is the step-up management of acne?
1. Single topical therapy
2. Topical combination therapy
3. Oral Abx
4. COCP
5. Oral isotretinoin
128
What are single topical therapies used for acne?
Topical retinoids and benzoyl peroxide
129
What are some topical combination therapies used for acne?
Topical retinoid, benzoyl peroxide, topical abx
130
What is the abx management of acne?
1. Tetracyclines = lymecycline/doxycycline/oxytetracycline
| 2. Erythromycin in pregnancy
131
When should tetracyclines be avoided for tx of acne?
1. Pregnant/breastfeeding women
| 2. Children <12y/o
132
What is the maximum length of time a single oral antibiotic should be used for acne vulgaris?
3m
133
What should always be co-prescribed with oral abx for acne and why?
Topical retinoid/BP, to reduce the risk of abx resistance
134
Should topical and oral abx be used in combination?
No
135
What may occur as a complication of long term abx treatment of acne?
Gram negative folliculitis
136
What abx is effective for management of gram negative folliculitis after long term abx tx of acne vulgaris?
High dose oral trimethoprim
137
What is a c/i to topical and oral retinoid treatment?
Oral isotretinoin, only under specialist supervision
138
Is there a role for dietary modification in pts with acne?
Supposedly not
139
How can you describe lichen planus?
1. 4Ps = Purple, pruritic, papular, polygonal rash on the flexor surfaces
2. Wickham's striae over the surface
3. Oral involvement in 50%
4. Koebner phenomenon
5. Nails = thinning of nail plate, longitudinal ridging
140
What are Wickham's striae?
Whitish lines visible in the papules of lichen planus and other dermatoses, typically in the oral mucosa
141
How can you describe lichen sclerosus?
Itchy white spots typically seen on the vulva of elderly women
142
What is lichen planus?
A skin disorder of unknown aetiology, most probably being immune-mediated
143
What are 3 causes of lichenoid drug eruptions?
1. Gold
2. Quinine
3. Thiazides
144
What is the management of lichen planus?
1. Topical steroids are mainstay
2. Benzydamine mouthwash or spray is recommended for oral lichen planus
3. Extensive lichen planus may require oral steroids or immunosuppression
145
Despite being called 'ringworm' what is the actual cause of ringworm?
Caused by a group of fungi called dermatophytes
146
What is tinea?
A term given to dermatophyte fungal infections
147
What are the 3 main types of tinea (anatomical)?
1. Tinea capitis
2. Tinea corporis
3. Tinea pedis
148
What is a cause of scarring alopecia, mainly seen in children?
Tinea capitis
149
What may form if tinea capitis is left untreated?
A kerion
150
What is a kerion?
A raised, pustular, spongy/boggy mass formed due to untreated tinea capitis
151
What are the most common causes of tinea capitis?
1. Trichophyton tonsurans most common
| 2. Microsporum canis
152
How does one acquire microsporum canis?
From cats and dogs
153
What is the management of tinea capitis?
1. Topical ketoconazole shampoo for first 2 weeks
2. Tricophyton tonsurans --> terbinafine
3. Microsporum canis --> griseofulvin
154
What are the main causes of tinea corporis?
1. Tricophyton rubrum
| 2. Trichophyton verrucosum
155
How does one acquire tricophyton verrucosum?
From contact with cattle
156
How does one treat tinea corporis?
Oral fluconazole
157
How can one differentiate between Tricophyton tonsurans and Microsporum canis?
Woods lamp --> Trichophyton does not readily fluoresce, Microsporum does
158
What may topical corticosteroids cause in pts with darker skin?
Patchy depigmentation
159
What is melasma?
Hyperpigmented brown/grey macules and patches, usually occurs in pregnancy women
160
What are some risk factors for melasma?
1. Darker skin
2. Sun exposure
3. NSAIDs
4. OCP/HRT
161
What is an example of a mild topical steroid?
Hydrocortisone 0.5-2.5%
162
What are 2 examples of a moderate topical steroid?
1. Betamethasone valerate 0.025%, a.k.a Betnovate RD
| 2. Clobetasone butyrate 0.05%, a.k.a Eumovate
163
What are 2 examples of potent topical steroids?
1. Fluticasone propionate 0.05%, a.k.a Cutivate
| 2. Betamethasone valerate 0.1% a.k.a Betnovate
164
What is an example of a very potent topical steroid?
Clobetasol propionate 0.05% (Dermovate)
165
What is betamethasone valerate aka?
Betnovate
166
What is Clobetasone butyrate aka?
Eumovate
167
What is Clobetasol propionate aka?
Dermovate
168
What is the finger tip rule?
1 FTU (finger tip unit) = 0.5g, sufficient to treat a skin area about twice that of the flat of an adult hand
169
What usually precipitates guttate psoriasis?
A streptococcal throat infection
170
What is the management for chronic plaque psoriasis?
1. Regular emollients ut reduces scale loss and reduce pruritis
2. 1st line = Potent corticosteroid OD + Vit D analogue OD
3. 2nd line = No improvement after 8 wks --> Vit D analogue BD
4. 3rd line = Potent steroid BD/coal tar BD
5. 4th line = Short-acting dithranol
171
When may systemic side effects be seen when using potent corticosteroids?
>10% TBSA
172
What is the recommended time scale for use of potent and very potent corticosteroids?
1. Potent = 8wks at a time
| 2. Very potent = 4wks at a time
173
What are some Vit D analogues that can be used for treatment of psoriasis?
1. Calcipotriol (Dovonex)
2. Calcitriol
3. Tacalcitol
174
How long should breaks be between steroids when using topical steroids for treatment of psoriasis?
4 weeks
175
What are some secondary care managements for plaque psoriasis?
1. Phototherapy
| 2. Systemic therapy
176
What are the phototherapy options for treatment of psoriasis?
1. Narrow band UVB 3x/week
| 2. PUVA = psoralen + UVA light
177
What are some s/e of phototherapy for psoriasis?
1. Skin ageing
| 2. SCC
178
What are some systemic therapies that can be used for psoriasis?
1. Methotrexate 1st line
2. Ciclosporin
3. Systemic retinoids
4. Biologics
5. Ustekinumab (IL12 & IL23)
179
What are some biologic agents used for treatment of psoriasis?
1. Infliximab
2. Etanercept
3. Adalimumab
180
What is the MOA of coal tar?
Probably inhibit DNA synthesis
181
What is the MOA of calcipotriol?
Vit D analogue which reduces epidermal proliferation and restores a normal horny layer
182
What is the MOA of dithranol?
Inhibits DNA synthesis, wash off after 30 mins
183
What is onychomycosis?
Fungal infection of the nails
184
What are 3 causes of onychomycosis?
1. Dermatophytes
2. Yeasts
3. Non-dermatophyte moulds
185
What accounts for 90% of cases of onychomycosis?
The dermatophyte Trichophyton rubrum
186
What is the main yeast that causes onychomycosis?
Candida
187
What are 2 RFs for onychomycosis?
1. DM
| 2. Age
188
What are 4 DDx for onychomycosis?
1. Psoriasis
2. Lichen planus
3. Yellow nail syndrome
4. Repeated trauma
189
What investigations should one do for suspected onychomycosis?
1. Nail clippings
| 2. Scrapings of the affected nail
190
Does onychomycosis need to be treated if it is asymptomatic and the pt is not bothered by the appearance?
No
191
What should be done before rx of onychomycosis?
Dx should be confirmed by microbiology
192
What is the management of dermatophyte-induced onychomycosis?
1st line = oral terbinafine/oral itraconazole as alternative
193
How long does it take to treat fingernail and toenail onychomycosis?
1. Fingernail = 6w-3m
| 2. Toenail = 3-6m
194
What % of pts with onychomycosis are successfully treated?
50-80%
195
What is the management of guttate psoriasis?
1. Most cases resolve spontaneously within 2-3m
2. No firm evidence to support abx for strep infection
3. Topical agents as per psoriasis
4. UVB phototherapy
5. Tonsillectomy may be necessary with recurrent episodes
196
What is pemphigus vulgaris?
An Autoimmune disease caused by antibodies directed against desmoglein 3, a cadherin-type epithelial cell adhesion molecule
197
In what pt demographic is pemphigus vulgaris more common?
Ashkenazi Jews
198
What are the some features of pemphigus vulgaris?
1. Mucosal ulceration most common
2. Skin blistering (flacced, easily ruptured vesicles and bullae)
3. Acantholysis on biopsy
4. Nikolsky's sign positive
199
What is the management of pemphigus vulgaris?
1. Steroids
| 2. Immunosuppressants
200
What is the first line treatment for seborrheic dermatitis?
Topical ketoconazole
201
What are 2 conditions associated with seborrheic dermatitis in adults?
HIV and Parkinsons
202
What is the management of scalp seborrheic dermatitis in adults?
1. OTC preparations containing zinc pyrithione (Head & Shoulders) and tar (Neutrogena T/Gel) are 1st line
2. 2nd line = ketoconazole
3. Selenium sulphide and topical corticosteroids may also be helpful
203
What is the management of face and body seborrheic dermatitis?
1. Topical antifungals e.g. ketoconazole
2. Topical steroids best used for short periods
3. Difficult to treat --> recurrences are common
204
What are 3 different allergy tests?
1. Skin prick tests
2. RAST
3. Skin path testing
205
What is a skin prick test useful for diagnosing?
Food allergies and pollen
206
After how long can a skin prick test be interpreted?
15 minutes
207
What does RAST stand for?
Radioallergosorbent test
208
How does RAST work?
It determines the amount of IgE that reacts specifically with suspected or known allergens, e.g. IgE to egg protein
209
How are RAST results given?
In grades from 0 (negative) to 6 (strongly positive)
210
What is RAST useful for diagnosing?
1. Food allergies
2. Inhaled allergens e.g. Pollen
3. Wasp/bee pollen
211
What is skin patch testing useful for?
Contact dermatitis
212
How is skin patch testing performed?
Around 30-40 allergens are placed on the back, patches removed 48 hours later with the results being read by a dermatologist a further 48 hours later
213
How can you differentiate between an amelanotic melanoma and a pyogenic granuloma?
A history of trauma
214
What is an alternative name for a pyogenic granuloma and why should you use it instead?
Should be called an eruptive haemangioma as it is neither a granuloma nor pyogenic
215
What are 3 RFs for pyogenic granulomas?
1. Trauma
2. Pregnancy
3. More common in women and young adults
216
What do pyogenic granulomas look like?
A small red/brown spot that rapidly progresses within days to weeks to form raised, red/brown lesions which are often spherical in shape. The lesions may bleed profusely or ulcerate
217
What is bullous pemphigoid?
An autoimmune condition causing subepidermal blistering of the skin, secondary to antibodies against hemidesmosomal proteins
218
What are some features of bullous pemphigoid?
1. Itchy, tense blisters typically around flexures
2. Blisters usually heal without scarring
3. Mucosa is usually spared
219
What is an SBA way to differentiate between pemphigus vulgaris and bullous pemphigoid?
PV has mucosal involvement , no mucosal involvement in BP (not the case in reality, but enough for SBAs)
220
What do you see on skin biopsy of Bullous pemphigoid?
Immunofluorescence shows IgG and C3 at the dermoepidermal junction
221
What is the mainstay of treatment for bullous pemphigoid?
Oral corticosteroids
222
What kind of malignancies is acanthosis nigricans associated with?
GI malignancies e.g. gastric and pancreatic cancer
223
What is lentigo maligna?
A precursor to lentigo maligna melanoma, that begins as a susicious flat freckle which can grow over 5-20 years to develop into a melanoma
224
What is the demographic of pts affected by lentigo maligna?
Older people on chronically sun exposed skin
225
What are the main 4 subtypes of melanoma?
1. Superficial spreading
2. Nodular
3. Lentigo maligna
4. Acral lentiginous
226
What is the most common melanoma?
SS
227
What is the second most common melanoma?
Nodular
228
What is the least common melanoma?
AL
229
What is Hutchinson's sign?
Melanonychia with pigmentation of the proximal nail fold, an important sign of subungual melanoma although is not an infallible predictor
230
What are 3 other rogue subtypes of melanoma?
1. Desmoplastic
2. Amelanotic
3. Elsewhere in body e.g. ocular
231
What is morphea?
A thickened area of skin due to localised scleroderma
232
What is a port-wine stain?
A capillary malformation seen at birth which usually requires no treatment
233
What is the management of a port wine stain?
Cosmetic camouflage or laser therapy (multiple sessions are required)
234
What is the management for pyoderma gangrenosum?
1. Oral steroids due to potential for rapid progression
| 2. Ciclosporin/infliximab for hard to treat cases
235
What is vitiligo?
An AI condition which results in the loss of melanocytes and subsequent depigmentation of the skin
236
What percentage of the population is affected by vitiligo?
1%
237
What phenomenon is seen with Vitiligo?
Koebner
238
What are 5 conditions associated with vitiligo?
1. T1DM
2. Addisons
3. AI thyroid diseases
4. Pernicious anaemia
5. Alopecia areta
239
What is the management for vitiligo?
1. Sunblock for affected areas
2. Camouflage makeup
3. Topical corticosteroids may reverse changes if applied early
4. ?role for topical tacrolimus and phototherapy
240
What is polymorphic eruption of pregnancy and some features of it?
1. Pruritic condition associated with last trimester
2. Lesions often first appear in abdominal striae
3. Management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
241
What is pemphigoid gestationis and what are some features of it?
1. Pruritic blistering condition usually seen in the 2nd or 3rd trimester
2. Lesions often first appear in the peri-umbilical region
3. Management: oral corticosteroids are usually required
242
What must you screen for when a pt presents with alopecia areata?
AI conditions
1. Thyroid disease
2. DM
3. Pernicious anaemia
243
What is alopecia areata?
A presumed AI condition causing localised, well demarcated patches of hair loss
244
What are 'exclamation mark' hairs indicative of?
Alopecia areata
245
What is the prognosis for alopecia areata?
1. 50% regrow by 1 year
| 2. 80-90% regrow eventually
246
What are some treatment options for alopecia areata?
1. Topical corticosteroids
2. Phototherapy
3. Dithranol
4. Topical minoxidil
5. Contact immunotherapy
6. Wigs
247
What is the most common cause of an itchy rash affecting the face and scalp?
Seborrheic dermatitis
248
Does seborrrheoic dermatitis involve the nasolabial folds?
Yes
249
Does acne rosacea involve the nasolabial folds?
No
250
How is a nickel dermatitis diagnosed?
Skin patch test
251
How does lichen sclerosus present?
Itchy, sore white plaque on vulva, typically in elderly woman
252
What is the management of lichen sclerosus?
Topical steroid and emollients
253
Why is followup required for lichen sclerosus?
Increased risk of vulval cancer
254
When is a skin biopsy required for lichen sclerosis?
If woman fails to respond to treatment or there is clinical suspicion of VIN or cancer
255
What is the oral abx of choice for treatment of erythrasma?
Erythromycin
256
What is erythrasma?
An infection caused by Corynebacterium minutissimum
257
How does erythrasma present?
Asymptomatic, flat, slight scaly, pink/brown rash usually found in the groin/axillae
258
What do you see under Wood's light in erythrasma?
Coral-red fluorescence
259
What is the prevalence of psoriasis?
2%
260
What are 2 HLA associations with psoriasis?
HLA B13 and B17
261
Is sunlight good or bad for psoriasis?
Good
262
What are 4 subtypes of psoriasis?
PFGPPE
1. Plaque (red scaly patches)
2. Flexural (smooth skin)
3. Guttate (teardrop)
4. Pustular
5. Palmoplantar
6. Erythrodermic
263
What are 5 complications of psoriasis?
1. Psoriatic arthropathy (10%)
2. Metabolic syndrome
3. Cardiovascular disease
4. VTE
5. Psychological distress
264
What causes scabies?
Sarcoptes scabiei
265
In what layer does the scabies mite lay its eggs into?
Stratum corneum
266
What causes the intense pruritis associated with scabies?
A delayed type IV hypersensitivity reaction to the mites/eggs which occurs around 30 days after the initial infection
267
What are the main features of scabies?
1. Widespread pruritis
| 2. Linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist
268
What is the management of scabies?
1. Permethrin 5% first line
| 2. Malathion 0.5% second line
269
How long does pruritis last in scabies?
Up to 4-6 weeks post eradication
270
What is pt guidance to give during scabies treatment?
1. Avoid close physical contact with others
2. All household contacts and close physical contacts should be treated, even if asymptomatic
3. Launder all clothing, bedding and towels on first day of treatment to kill off mites
271
When do you see crusted 'Norwegian' scabies?
Pts with suppressed immunity, especially HIV
272
What is the treatment of choice for crusted Norwegian scabies?
Ivemectin and Isolation
273
What produces a symmetrical white lace-like pattern on the buccal mucosa?
Lichen planus
274
What is leukoplakia?
White, hard spots on the mucous membranes of the mouth, more common in smokers
275
What other conditions must be considered before oral leukoplakia, which is a Diagnosis of Exclusion?
Candidiasis and Lichen Planus
276
Why are biopsies usually performed on oral leukoplakias?
To exclude alternative diagnoses e.g. SCC
277
What percentage of leukoplakias undergo malignant transformation to SCC?
1%
278
What 2 drugs can cause acanthosis nigricans?
OCP and nicotinic acid
279
How long does the rash from pityriasis rosea typically last?
6-12 weeks from the presentation
280
What are some features of acne rosacea?
1. Nose, cheeks and forehead
| 2. Flushing, erythema, telangiectasia --> papules and pustules
281
What is the management of acne rosacea?
1. Topical metronidazole for mild symptoms
2. More severe disease with systemic Abx e.g. oxytetracycline
3. Daily high factor sunscreen
282
What is a late complication of severe rosacea?
Rhinopyma
283
At what TBSA must superficial burns be referred to secondary care in children and adults?
>2% TBSA in children, >3% TBSA in adults
284
What are 4 skin manifestations of SLE?
1. Photosensitive malar rash
2. Discoid lupus
3. Alopecia
4. Livedo reticularis
285
What derm cancer are renal transplant pts at increased risk of?
SCC
286
What is the 1st line treatment for impetigo?
Topical fusidic acid
287
What are 3 things that must be monitored for in the treatment of erythroderma?
1. Dehydration
2. Infection
3. High output HF
288
What is erythroderma?
A term used when more than 95% of the skin is involved in a rash of any kind
289
What are some causes of erythroderma?
1. Eczema
2. Psoriasis
3. Drugs e.g. gold
4. Lymphomas, leukaemias
5. Idiopathic
290
What are the first line treatments for tinea pedis?
1. Topical imidazole
2. Topical undecanoate
3. Topical terbinafine
291
What is the most common type of melanoma that has the typical diagnostic features of a changing mole?
Superficial spreading melanoma
292
What condition presents with a herald patch?
Pityriasis rosea
293
What is the most common precipitant of a pyogenic granuloma?
Trauma
294
What is the difference in nature of UV exposure that leads to SCCs and BCCs respectively?
1. SCC = chronic long term expsosure
| 2. BCC = sporadic exposure with burning
295
What is a useful stat for risk of subsequent SCC in actinic keratosis?
In pts with 7 actinic keratoses, the risks of subsequent SCC is 10% at 10 years
296
What are 5 types of BCC?
1. Nodular
2. Superficial
3. Morpeaform
4. Cystic
5. Basosquamous
297
What is a dome-shaped erythematous lesion that develops over a period of days and grows rapidly, that often contain a central pit of keratin?
Keratoacanthoma
298
Where does erythema nodosum occur?
Typically on shins, also elsewhere e.g. forearms, thighs
299
What causes erythematous nodules over forearms with a high calcium?
Erythema nodosum due to sarcoidosis
300
How do you differentiate between spider naevi and telangiectasia?
Press on them and watch them fill
1. Spider naevi fill from centre
2. Telangiectasia fill from the edge
301
How would one describe a spider naevus?
A central red papule with surrounding capillaries that blanch upon pressure
302
What are some causes of spider naevi?
1. Idiopathic
2. Liver disease
3. COCP
4. Pregnancy
303
What is the management of eczema herpeticum?
IV Aciclovir
304
What is the first line treatment for hyperhidrosis?
1. Topical aluminium chloride preparations 1st line
2. Iontophoresis
3. Botulinum toxin
4. Surgery
305
What surgical procedure can be undertaken for hyperhidrosis?
Endoscopic transthoracic sympathectomy
306
What is erythema ab igne?
A skin disorder caused by over exposure to infrared radiation in the form of heatr
307
What are the features of erythema ab igne?
Reticulated, erythematous patches with hyperpigmentation and telangiectasia
308
What is a complication of chronic erythema ab igne?
SCC
309
What is Bowen's disease and who is it typically found in?
SCC in situ, and is commonly in elderly females
310
What is the risk of developing invasive SCC in Bowen's disease?
3%
311
What are the management options for Bowen's disease?
1. Topical 5-Fu or imiquimod
2. Cryotherapy
3. Excision
312
What causes a 'ruddy' complexion and pruritis after a warm bath?
Polycythaemia
313
What is the most common cause of oedema 2 weeks post extensive burns?
Hypoalbuminaemia
314
When is an ultrasound necessary for a lipoma?
If it is >5cm
315
What is a lipoma?
A common, benign tumour of adipocytes
316
What are 3 features of a lipoma?
Smooth, mobile, painless
317
What are features suggestive of development of a liposarcoma?
1. Size 5>cm
2. Increasing size
3. Pain
4. Deep anatomical location
318
What has a 'stuck-on' appearance?
Seborrhoeic keratoses
319
What is the most effective tx for prominent telangiectasia in acne rosacea?
Laser therapy
320
How would you describe pyoderma gangrenosum?
Initially a small red papule that develops into deep, red necrotic ulcers with a violaceous border
321
What is the first line treatment for pyoderma gangrenosum?
1. Oral steroids
| 2. Others = ciclosporin, infliximab
322
What causes acne vulgaris?
Obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules
323
Is propionibacterium acnes aerobic or anaerobic?
Anaerobic
324
What two terms do sebaceous cysts encompass?
Epidermoid and pilar cysts
325
What is am epidermoid cyst?
A proliferation of epidermal cells within the dermis
326
What is a pilar cyst?
Benign cysts that derive from the outer root sheath of the hair follicle
327
What is a characteristic feature of a sebaceous cyst?
Central punctum
328
What is the most common cause of toxic epidermal necrolysis?
Drug reaction
329
What are some drugs known to cause TEN?
1. P = penicillins, phenytoin
2. A = allopurinol
3. NSAIDs
4. Carbamazepine
5. Sulphonamides
330
What is the management of TEN?
1. Stop precipitating factor
2. Supportive care often in ITU
3. IVIG is now first line
4. Immununosuppressive agents e.g. ciclosporin and cyclophosphamide
331
What are some management options for a BCC?
1. Surgical removal
2. Curettage
3. Cryotherapy
4. Topical cream: FU, imiquimoid
5. Radiotherapyu
332
What is the most likely diagnosis in an uncircumsised man who has developed a tight white ring around the tip of his foreskin and phimosis?
Lichen sclerosus
333
What is Zoon's balanitis?
A benign condition of uncertain origin affecting uncircumcised men. Presents with orange-red lesions with pinpoint redder spots on the glans and adjacent areas of the foreskin
334
What is circinate balanitis?
Chronic balanitis in those with reactive arthritis. It presents with a well-demarcated erythematous plaque with a ragged white border
335
What is erythroplasia of Queyrat?
In-situ SCC of the penis
336
What is the most common s/e of isotretinoin?
Dry skin
337
What proportion of pts have a long term remission or cure following a course of oral isotretinoin?
2/3rds
338
What are some s/e of isotretinoin?
1. Teratogenicity
2. Dry skin and eyes
3. Low mood
4. Raised triglycerides
5. Hair thinning
6. Nosebleeds
7. Intracranial HTN
8. Photosensitivity
339
What is the single most important prognostic factor in malignant melanoma?
Depth of melanoma (Breslow thickness)
340
What should pts be acne scarring be referred for?
Oral isotretinoin
341
What is the prognosis of a paediatric strawberry naevus?
Increase in size until 6-9 months before regressing over next few years, around 95% resolve by 10 y/o
342
What is the formal term for a strawberry naevus?
Capillary haemangioma
343
What are some complications of strawberry naevi?
1. Mechanical e.g. obstructing visual fields/airway
2. Bleeding
3. Ulceration
4. Thrombocytopenia
344
What are some medical treatments for strabwerry naevi?
1. Oral propranolol
| 2. Topical timolol
345
What is a cavernous haemangioma?
A deep capillary haemangioma
346
When is treatment usually indicated for a capillary haemangioma?
If the lesion is causing a mechanical problem or is bleeding
347
What is a rare but important s/e to be aware of with penicillins?
TEN
348
What are 2 skin disorders associated with pregnancy?
1. Polymorphic eruption of pregnancy
| 2. Pemphigoid gestationis
349
What kind of reaction is erythema multiforme?
A hypersensitivity reaction, most commonly triggered by infections. It may be divided into major and minor forms.
350
What are some features of erythema multiforme?
1. Target lesions
2. Initially seen on back of hands/feet before spreading to torso
3. Upper limbs more commonly affected than lower limbs
4. Pruritis occasionally seen and is usually mild
351
What are some causes of erythema multiforme?
1. Idiopathic
2. Infection = Viral, bacterial
3. Drugs
4. CTD e.g. SLE
5. Sarcoidosis
6. Malignancy
352
What is the most common viral cause of erythema multiforme?
HSV
353
What are some bacterial causes of erythema multiforme?
Mycoplasma, Streptococcus
354
What are some drugs that cause erythema multiforme?
1. Penicillins
2. Sulphonamides
3. Carbamazepine
4. Allopurinol
5. NSAIDs
6. OCP
7. Nevirapine
355
What is erythema multiforme major?
A more severe form, is associated with mucosal involvement
356
If you see a painful rash, what is it most likely to be in an adult?
Shingles
357
What is the treatment for shingles?
Oral aciclovir
358
What is shingles?
An acute, unilateral, painful blistering rash caused by reactivation of VZV
359
To whom is the shingles vaccine offered?
All pts aged 70-79 y/o
360
What are some features of the shingles vaccine?
Is live attenuated and is given subcutaneously
361
What is the main contraindication to the shingles vaccine?
Immunosuppression as it is a live attenuated vaccine
362
What is the pathophysiology of erythema nodosum?
Inflammation of the subcutaneous fat
363
What are 4 AVMs that can occur in HHT?
1. Cerebral
2. Spinal
3. Pulmonary
4. Hepatic
364
What is the eponym for HHT?
Osler-Weber-Rendu Syndrome
365
What is the inheritance of HHT?
Autosomal dominant, although 20% cases are spontaneous
366
What are the diagnostic criteria for HHT?
3 or more out of:
1. Epistaxis
2. Telangiectases
3. Visceral lesions
4. FHx
367
What 2 condiitons must always be considered in children with new-onset purpura?
ALL and meningococcal disease
368
What is purpura?
Bleeding into the skin from small blood vessels that produces a non-blanching rash
369
What could be causing petechiae in the upper body after a prolonged cough?
Raised SVC pressure
370
What is acne fulminans?
A very severe acne associated with systemic upset e.g. fever
371
What is the management of acne fulminans?
Oral steroids
372
What is the eponym for ataxia telangiectasia?
Louis-Bar syndrome
373
What is the management for dermatitis herpetiformis?
1. Gluten-free diet
| 2. Dapsone
374
What are some ocular complications of acne rosacea/
Blepharitis, keratitis, conjunctivitis
375
What are the 2 main types of contact dermatitis?
1. Irritant contact dermatitis
| 2. Allergic contact dermatitis
376
What are 2 ways in which cement can cause a contact dermatitis?
1. Alkaline nature can cause irritant contact dermatitis
| 2. Dichromates in cement can cause allergic contact dermatitis
377
What is the management of allergic contact dermatitis?
Topical treatment with a potent steroid
378
What is the most aggressive form of melanoma?
Nodular melanoma
379
How does a nodular melanoma present?
Red or black lump that oozes/bleeds, on sun-exposed skin
380
What could cause lethargy, pallor and generalised pruritis?
Anaemia
381
How would acral lentiginous melanoma present?
Pigmentation of the nail bed affecting the proximal nail fold (Hutchinson's sign)
382
What is the rarest form of melanoma overall, but is the commonest form in people with darker skin?
Acral lentiginous melanoma
383
What are cherry haemangiomas?
Benign skin lesions which contain an abnormal proliferation of capillaries
384
What is the eponym for cherry haemangiomas?
Campbell de Morgan spots
385
What are some features of cherry haemangiomas?
1. Erythematous, papular lesions
2. Typically 1-3mm in size
3. Non-blanching
4. Not found on mucous membranes
386
What does pityriasis rosea often follow?
A viral infection
387
What are 3 triggers for acne rosacea?
1. Sun exposure
2. Hot drinks
3. Sun exposure
388
Which of the melanomas invades aggressively and metastasises early?
Nodular melanoma
389
What is the most significant complication of PUVA therapy for psoriasis?
SCC
390
What is PUVA therapy?
Psoralen + UV A light therapy
391
What are the features of Pellagra?
Diarrhoea
Dementia
Dermatitis
Death
392
What is Pellagra?
Vitamin B3 (Niacin) deficiency
393
What is a cause of Pellagra to be aware of?
Isoniazid therapy
394
What do you call Pellagra-induced dermatitis if it is around the neck?
Casal's necklace
395
What is used to calculate the volume of IV fluid required for resuscitation in the first 24 hours after a burn?
Parkland formula
396
What is the most common cause of erythema multiforme?
HSV
397
Why is oral ketoconazole no longer suggested?
Due to hepatotoxicity
398
What is an embarrassing s/e of ketoconazole?
Gynaecomastia
399
What is the most common malignancy associated with acanthosis nigricans?
GI adenocarcinoma
400
What is the first line treatment for lichen sclerosus?
Strong topical steroid e.g. clobetasol propionate
401
How should you treat lichen sclerosus if steroids dont work?
Topical tacrolimus
402
What scoring system can be used for hirsutism?
Ferriman-Gallwey scoring system
403
What is hirsutism?
Excess hair growth in women following a male distribution pattern
404
What is hypertrichosis?
Excessive hair growth over and above the normal for age, sex and race of an individual
405
What are some causes of hirsutism?
1. PCOS (most common)
2. Cushings
3. CAH
4. Androgen therapy
5. Obesity (insulin resistance)
6. Adrenal tumour
7. Androgen secreting ovarian tumour
8. Drugs = phenytoin, steroids
406
What are some managements for hirsutism?
1. Weight loss if overweight
2. Contraception e.g. co-cypryndiol
3. facial = topical eflornithine
407
Why should co-cyprindiol not be used long term?
Due to increased risk of VTE
408
What are some causes of hypertrichosis?
1. Drugs
2. Congenital
3. Anorexia nervosa
4. Porphyria cutanea tarda
409
What is serborrhoeic dermatitis?
An inflammatory reaction to Malassezia furfur
410
What can exacerbate acne rosacea?
Sunlight, drugs, post-partum
411
What phenomenon can cause molluscum contagiosum to appear at sites of injury?
Koebner phenomenon
412
In what conditions can one see the Koebner phenomenon?
1. Psoriasis
2. Vitiligo
3. Warts
4. Lichen planus
5. Lichen sclerosus
6. Molluscum contagiosum
413
What is the first line treatment for hyperhidrosis?
Topical aluminium chloride preparations (roll-on applied at night time)
414
How should emollient be applied for eczema?
1. Initially 2-3x daily, increase up to every hour if the skin is very dry
2. Immediately after showering
3. Dont rub it in, leave it to soak in
415
What are some management options for eczema?
1. Emollients
2. Topical steroids
3. UV radiation
4. Immunosuppressants
416
What are some immunosuppressants that can be used to treat eczema?
1. Ciclosporin
2. Antihistamines
3. Azathioprine
417
What is the mainstay of treatment for lichen planus?
Topical steroids
418
What are some features of granuloma annulare?
1. Papular lesions that ore often slightly hyperpigmented and depressed centrally
2. Typically occur on dorsal surfaces of the hands and feet, and on the extensor aspects of the arms and legs
419
Where on the body are keloid scars most likely to form?
Sternum
420
What are keloid scars?
Tumour-like lesions that arise from the connective tissue of a scar and extend beyond the original dimensions of the wound
421
What are some prediposing factors for keloid scars?
1. Ethnicity (darker skin)
| 2. Young adults
422
Where can incisions be made to reduce the chance of keloid scars from forming?
If incisions are made along relaxed skin tension lines
423
What is the management of keloid scars?
1. Intra-lesional steroids e.g. triamcinolone
| 2. Excision is sometimes required
424
What are milia?
Small, benign, keratin-filled cysts that typically appear around the face. They may appear at any age but are more common in newborns.
