dermatology Flashcards

1
Q

yellow, greasy non pruritic scales on the scalp, classically with no underlying erythema, seen in babies
likely diagnosis?

A

Infantile Seborrhoeic Dermatitis, more commonly known as Cradle Cap

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2
Q

Tx for cradle cap

A

emollient (moisturiser) to help loosen the scales
then gently brush baby’s scalp with a soft brush and then wash it with baby shampoo

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3
Q

RF for atopic dermatitis

A

allergic rhinitis (hayfever),
age <5 years,
family history of eczema,
PMH/FH of atopy (food allergies, asthma)

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4
Q

contact dermatitis vs atopic dermatitis

A

contact dermatitis
- results from external factors
- type 4 hypersensitivity
- tested for vis skin patch test

atomic dermatitis
- internal skin condition
- type 1 hypersensitivity (IgE)
- tested for via skin prick tets

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5
Q

sites of involvement of atopic dermatitis in infants

A

cheek
forehead
extensor surfaces

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6
Q

sites of involvement of atopic dermatitis in children

A

flexures - particularly the wrists, ankles, and antecubital and popliteal fossa

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7
Q

2 signs of chronic atopic dermatitis

A

lichenification (thick leathery skin due to constant scratching)
hyperpigmentation

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8
Q

what medical emergency can present in children with atopic dermatitis

A

eczema herpeticum - presenst as rapidly growing painful rash

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9
Q

describe the presentation of eczema herpeticum

A

rapidly growing painful rash
punched out lesions
commonly seen in children with atopic dermatitis

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10
Q

cause of eczema herpeticum

A

HSV 1 or 2

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11
Q

Tx for eczema herpeticum

A

IV acyclovir - urgent as can be life threatening

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12
Q

levels of what are elevated in atopic dermatitis

A

IgE

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13
Q

Ix for atopic dermatitis

A

IgE levels
skin prick testing

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14
Q

Ix for contact dermatitis

A

skin patch testing

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15
Q

Tx for atopic dermatitis, normal and in severe cases

A

Emollients → improve skin barrier function by rehydrating the skin

Topical Corticosteroids → hydrocortisone

Severe Cases ⇒ systemic immunosuppressive agents (Oral Ciclosporin)

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16
Q

common causes of viral exanthema

A

chickenpox (varicella),
measles,
rubella

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17
Q

what is viral exanthema and where on body is it usually found

A

Widespread skin rash accompanying a viral illness

more likely to occur on trunk

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18
Q

Ix for viral exanthema

A

viral swab
blood tests

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19
Q

Tx for viral exanthema

A

Antipyretics → paracetamol
Moisturising emollients to reduce itch

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20
Q

where do pressure sores usually happen

A

over a bony prominence eg sacrum or heel

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21
Q

RF for pressure sores

A

immobility,
recent surgery
intensive care stay,
diabetes,
malnutrition

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22
Q

what score is used to screen for pts who are risk of developing pressure sores and what does it take into account

A

Waterlow score

Takes into account
BMI,
nutritional status,
skin type,
mobility
continence

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23
Q

stages 1-4 of pressure ulcers/sores

A

Stage 1 ⇒ nonblanchable erythema of intact skin.
Stage 2 ⇒ loss of dermis +/- epidermis. Superficial ulcer.
Stage 3 ⇒ loss of all skin layers (full thickness).
Stage 4 ⇒ extensive destruction, tissue necrosis, or damage to muscle, bone or supporting structures

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24
Q

describe the erythema in pressure sores/ulcers

A

non blanchable

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25
what are the clinical features of a pressure sore/ucler
over bony prominence eg scream/heel non blanch able erythema described skin perfusion (^CRT) painful - (different from neuropathic ulcers which are painless) signs of wind infection eg purulent drainage, foul smell
26
Ix for pressure sores
Evaluate for predisposing factors → blood glucose, HbA1C, serum albumin (assess malnutrition) Check for infection → leukocytosis and increased CRP
27
management of pressure sores/uclers
Pressure relief over affected area Frequent position changes (every 2 hrs) for immobile patients Moist wound environment (encourages ulcer healing) Analgesia (paracetamol, ibruprofen) Ensure good Nutrition Wound Management → cleaning & dressings
28
management of stage 3/4 pressure sores/uclers in pt who are and aren't suitable for surgery
Debridement of necrotic tissue (if not suitable for surgery) Surgical debridement and reconstruction with flap formation (if suitable for surgery)
29
which layers of the skin are infected in cellulitis
deep dermis and subcutaneous tissue
30
most common causative bacteria of cellulitis
Streptococcus pyogenes (catalase -ve) Staphylococcus aureus (catalse +ve)
31
RF for cellulitis
obesity diabetes, venous insufficiency, eczema, oedema
32
describe the skin, lesions and systemic symtopoms of cellulitis
red painful hot swelling poorly defined lesions fever, chills, nausea, headaches
33
what is erysipelas in cellulitis and what is it cause by
causes well defined lesion More superficial, limited version of cellulitis Caused by streptococcus pyogenes.
34
where does cellulitis most commonly occur
legs (shins)
35
Ix for cellulitis
Clinical Diagnosis → only request further tests if signs of systemic illness or septicaemia High WCC and CRP Skin Swab MCS → can identify pathogen and antibiotics susceptibility If patient admitted and septicaemia suspected → blood cultures and sensitivities
36
which classification is used to guid management of cellulitis
ERON classification
37
class I, II, III of cellulitis and how to manage each
Class I (no systemic systems or co-morbidities) → managed in primary care with oral antibiotics Class II (systemically unwell or systemically well with co-morbidity) → short term hospitalization Class III (significant systemic upset) or IV (sepsis or nec fasc) → urgent hospital admission
38
first line Tx for mild/moderate cellulitis, and what is the replacement if have penicillin allergy
Flucloxacillin → 1st line treatment for mild/moderate cellulitis If Penicillin Allergic → clarithromycin, erythromycin (in pregnancy), or doxycycline
39
Tx for cellulitis if severe systemic symptoms (eg. septic signs, tachycardic + hypotensive) or significant comorbidites
hospital admission + IV co-amoxiclav, cefuroxime, clindamycin or ceftriaxone
40
what can psoriatic skin manifestations be made up of
plaques papules
41
describe the papules in psoriasis
erythematous circumscribed / well demarcated scaly purple / silver
42
what pathophysiology causes the papules and plaques in psoriasis
abnormal T cell activity --> stimulates keratinocyte proliferation
43
describe the clinical course of psoriasis
relapsing course, with symptoms free intervals
44
describe the 3 types of psoriatic skin problems
plaque psoriasis - raised inflamed plaque lesions with a superficial silvery-white scaly eruption flexure psoriasis - skin is smooth. Occurs on skin creases or flexures (ie. groin, armpits). guttate psoriasis - widespread, erythematous, fine, scaly papules (water drop appearance) on trunk, arms, and legs. The lesions often erupt after an upper respiratory infection (frequently triggered by a streptococcal infection- fever and sore throat)
45
what exacerbates and relieves plaque psoriasis
exacerbates: BBs, NSAIDs, ACEi, lithium receives: sun exposure
46
what triggers guttate psoriasis
URTI esp strep infection
47
Tx of guttate psoriasis
phototherapy
48
in psoriasis in which order do arthritis and skin manifestations happen
1st arthritis, then skin lesions develop
49
describe psoriatic arthritis pattern and what the 2 main features are
asymmetrical arthritis pattern 2 main features 1. DIP swelling - "pencil in cup deformity" 2. dactylitis (sausage fingers)
50
which gene is psoriatic arthritis linked to
HLA-B27
51
Tx of psoriatic arthritis
NSAIDs and DMARDs (methotrexate)
52
which medication should be avoided in psoriatic arthritis to avoid skin lesion flare ups
oral steroids
53
describe nail manifestations of psoriasis
pitting onycholysis (seperation of the nail from the nail bed)
54
what is Koebner phenomenon
skin lesions caused by trauma (physical stimuli or skin injury)
55
what is Auspitz sign
small pinpoint bleeding when scales are scraped off
56
1st and 2nd line treatment
1st line topical corticosteroid (hydrocortisone) + topical vitamin D analogue (calcipotriol) Corticosteroids reduce inflammation, Vitamin D reduced keratinocyte proliferation 2nd line Phototherapy (secondary care) → narrowband ultraviolet B light
57
what is 1st line systemic Tx for psoriasis
oral methotrexate
58
why should steroids for psoratic skin conditions not be used for more than 8 weeks
can cause - skin atrophy - rebound symptoms - striae
59
what's another name for urticaria
hives
60
describe the lesions of urticaria
"wheals" BLANCHING smooth raised skin oedematous pruritic painless erythematous rapidly developing (minutes) short lived (<24hrs) leaves no skin markings once resolved
61
is urticaria blanching or non blanching
BLANCHING
62
contrast causes of acute or chronic urticaria
acute: allergy chronic: exposure to heat/cold, pressure, sunlight, vibration, Ach release, water
63
which drugs can cause urticaria
aspirin penecillin NSAIDs opiates
64
what are urticaria marks called
wheals
65
what other swelling is urticaria associated with
angioedema (swelling of face, tongue, lips)
66
what is urticarial vasculitis
chronic / recurrent urticaria due to affected small blood vessels in the skin
67
what Ix do you do if you suspect urticarial vasculitis
CRP and ESR
68
1st line Tx for urticaria
Trigger identification & avoidance antihistamine (loratadine or cetirizine)
69
Tx for severe / recurrent episodes of urticaria
prednisolone
70
which part of the skin does necrotising fasciitis affect
subcutaneous soft tissue
71
contrast type 1 and 2 necrotising fasciitis
type 1 (more common) - polymicrobial - aerobes and anaerobes - common in diabetics following surgery type 2 - monomicrobial - strep pyogenes
72
RF for necrotising fasciitis
immunosuppressed / diabetes SGLT2 inhibitors IVDU surgery cutaneous trauma varicella zoster infection
73
most common site for necrotising fasciitis
perineum - fourniere's gangrene
74
describe presentation of necrotising fasciitis
acute onset erythema and oedema systemic features of infection: - hypotension - tachycardia - palpitations -N&V - fever - tachypnoea - lightheadedness
75
2 signs of advanced necrotising fasciitis
delirium crepitus
76
Ix for necrotising fasciitis in order
1) surgical exploration 2) bloods and tissue culture
77
Tx for necrotising fasciitis
urgent surgical debridement Abx (give empirical first, then specify when cultures come back)
78
which pts have higher mortality with necrotising fasciitis
patients who develop shock and end-organ damage
79
what virus causes chicken pox
Varicella zoster virus (VXV)
80
what does HSV1 primarily cause
oral and genital herpes
81
what does HSV2 primarily cause
genital herpes
82
what is the name for severe inflammation of most of the body's skin surface - redness, scaling
erythroderma
83
what is sezary syndrome
erythroderma + lymohadenopathy + heaptosplenomegaly
84
itchy red rash of pustules in an area around hair follicles, most common on neck / armpit / groin diagnosis?
folliculitis
85
very itchy red rash made of small red lesions in the groin area likely diagnosis
scabies
86
what colour are genital warts
flesh coloured
87
prognosis of varicella zoster in children vs adults
children: self limiting adults: associated with complications, such as secondary bacterial infection, encephalitis, and pneumoni
88
pushed out lesion with well emaciated edges painful arterial insufficiency prolonged CRT poor pulses ischaemic changes eg hair loss, smooth shiny skin diagnosis
arterial ulcer?
89
ulcer after physical insult to area, hemosiderin deposition diagnosis?
traumatic ulcer this is secondary to vascular insufficiency and the hemosiderin deposits here suggests underlying venous insufficiency.
90
painful ulcers usually affects legs cribriform healing pattern undermined edges violaceous borders associated with IBD can be caused by minor injury to area: starts off as small red lesion then rapidly widens and deepens diagnosis?
pyoderma gangrenosum
91
causes of erythroderma
Dermatitis: Atopic dermatitis, seborrhoeic dermatitis, contact dermatitis Psoriasis Pityriasis rubra pilaris Drug allergies Idiopathic triggers Sezary syndrome, a type of cutaneous T-cell lymphoma, which leads to erythroderma, lymphadenopathy, and hepatosplenomegaly. It is defined by the presence of Sezary cells, which are atypical T cells, in the peripheral blood circulation.
92
purpuric rash abdo pain arthralgia diagnosis?
henoch-Schonlein purpura
93
what is telangiectasia
spider veins (small, red and purple clusters)
94
what does CREST syndrome entail
Calcinosis: Calcium skin deposits Raynaud's phenomenon Esophageal dysfunction: Sclerodactyly: Skin damage on fingers - tight shiny skin on fingers, causes them to curl at tip Telangiectasia: Spider veins
95
another name for CRESt sydrome
limited cutaneous systemic sclerosis
96
which antibodies are associated with CREST syndrome / imited cutaneous systemic sclerosis
anti centromere antibodies
97
what is erythema nodosum
tender, red bumps, usually found symmetrically on the shins
98
prodromal illness followed by the sudden appearance of a widespread, painful, erythematous rash. A least two mucosal sites are involved diagnosis?
Stevens-Johnson Syndrome (SJS)
99
causes of Stevens-Johnson Syndrome (SJS)
usually adverse drug reaction Sulphonamides (such as Co-trimoxazole), Beta-lactams (such as Penicillin) anti-convulsants (such as Phenytoin).
100
pt has UTI for which she starts taking medication, the develops painful sudden inset rash and ulcers on lips and genitals what is the diagnosis and the cause if it
stevens-johnson syndrome caused by cotrimoxazole (med for UTI)
101
pt has bacterial tonsillitis and sore throat followed by rash on her shins. what is the cause of her erythema nodosum
strep pyogenes
102
describe the rash seen in meningitis
non blanching palpable purpuric
103
what is erythema multiform
dye to allergic reaction to medication of infection - esp HSV eruption of target lesions spreading from the distal limbs to the trunk only affects ONE mucosal site
104
if pt with psoriasis on education develops swollen gums, which med likely caused this
ciclosporin
105
cyclosporin side effects
the 5 H’s: hypertrophy of the gums, hypertrichosis (excessive hair growth) hypertension, hyperkalaemia hyperglycaemia (diabetes)
106
what abdominal issue can occur with Henoch-Schonlein purpura
intussusception
107
describe the rash in Henoch-Schonlein purpura
Henoch-Schonlein purpura presents with bio pain, arthirtritis, renal issues, intussusception
108
which medication worsens psoriasis
beta blockers, ACEi, NSAIDs, lithium
109
what is herpes zoster (shingles) caused by
reactivation of varicella zoster virus
109
how does herpes zoster present
unilateral blistering lesions with sensory derangement - common in immunocompromised
110
Tx for herpes zoster
mild = analgesia and calamine lotion seere = acyclovir
111
history of stress and scratching, one single play on back of neck or perineum diagnosis?
lichen simplex chronicus
112
what is tuberous slcerosis
rare genetic condition that causes mainly non-cancerous (benign) tumours to develop in different parts of the body
113
tuberous sclerosis skin manifestation
angiofibromas - firm pales in a butterfly distribution across face shagreen patch - Leathery patch on sacrum, that is dimpled like orange peel fleshy tumour that grow from nail folds ovals of hypo pigmented skin that fluoresce under wood's light
114
what are dermatophytoses
fungal infection of skin and nails
115
triggers for psoriasis
Skin trauma (Koebner phenomenon) Infection: Streptococcus, HIV Drugs: B-blockers, Anti-malarials, Lithium, Indomethacin/NSAIDs (BALI) Withdrawal of steroids Stress Alcohol + smoking Cold/dry weather
116
characteristic feature of impetigo
gold crusting
117
what should you remember about the distribution of intermittent claudication
it is BILATERAL
118
which medication us used in the treatment of pruritus due to biliary obstruction
cholestyramine
119
respiratory symptoms erythema nodosum no recent travel history or contacts likely diagnosis?
sarcoidosis (lack of travel history makes TB less likely)
120
acute hypersensitivity reaction with limited or no mucosal involvement target lesions occurs after infection - esp HSV (presents w cold sores on lips)
erythema multiform
121
what presents with target lesions
erythema multiform
122
what presents with annular lesions
Tinea infections, caused by a dermatophyte fungus commonly known as ringworm
123
what presents with discoid lesions
discoid eczema discoid lupus erythematosus
124
what is the name for painful open pustular ulcers that have a blue overhanging edge, and which condition are they commonly seen in
pyoderma gangrenosum IBD
125
dermatological manifestation of TB
scrofuloderma, a cold, painless abscess in then which can ulcerate erythema nodosum - raised red ender rash on shins
126
what is given to a pt with urticaria who hasn't responded to antihistamines
oral prednisolone
127
which condition has a flu like prodrome followed by the development of an erythematous macular rash with ulceration of the pharynx and buccal mucosa
Stevens–Johnson syndrome (SJS)
128
what is erythroderma and how does it present
serve inflammation of most of body's skin surface redness and scaling starts in patches and then spreads all over body life threatening "Generalised erythema, pruritus and scaling"
129
causes of erythroderma
psoriasis reaction to medication
130
what is Seborrheic dermatitis
common skin condition that mainly affects your scalp. It causes scaly patches, inflamed skin and stubborn dandruff. affects oily ares of skin which produce sebum
131
describe the appearance of a wheal
raised lesion - skin coloured swelling surrounded by erythema
132
what is Toxic epidermal necrolysis
life-threatening skin disorder characterized by a blistering and peeling of the skin. This disorder can be caused by a drug reaction—often antibiotics or anticonvulsives.
133
raised red tender rash seen symmetrically on shins and pt is having trouble breathing diaganosis?
erythema nodosum caused by TB or sarcoidosis
134
bullseye rash occurs after tick bite - associated with Lyme disease diagnosis?
erythema migrans
135
what is compartment syndrome and when/where is pain felt
commonly occurs after fracture of leg swelling/tightness -> raised pressure reduces blood supply, causing tissue necrosis pain is in the front leg and is worse on pass ankle dorsiflexion (no blisters/blackened appearance of skin)
136
pt injured themselves and now has a rash on same area. what is the term given to this presentation?
Koebner's phenomenon (occurs in psoriasis)
137
what condition does Hyperproliferation of cells causing a decreased skin turnover time cause
psoriasis
138
what does a genetic defect in the skin barrier
atopic dermatitis
139
what medication should be used and what should be avoided for the pain associated with chicken pox
use paracetamol avoid NSAIDs eg ibuprofen as can cause necrotising fasciitis
140
when can a child with chicken pox return to school
when all the lesions have crusted over
141
which condition is mucous membrane involvement characteristic of
Steven-Johnson's syndrome
142
which bacteria cause impetigo - rash with honey coloured crusts
staph aureus strep pyogenes
143
erythema nodosum vs dermatitis herpetiformis
erythema nodosum - painful patches on legs - caused by IBD dermatitis herpetiformis - itchy, blistering - caused by coeliac disease
144
describe a venous ulcer, and what 2 other features are likely to be seen on the legs as well
painless granulated pink-red base medial aspect of lower leg associated with oedema and varicose veins
145
purple - flat topped plaques appearing on skin very itchy pt recently started new med diagnosis?
lichenoid eruption
146
girl has had rashes before but has suddenly presented with a new different looking one (multiple red, monomorphic blisters and erosions across her face and neck) she has a fever and feels unwell diagnosis and Tx?
eczema herpeticum as a complication of atopic eczema IV acyclovir
147
first and second line Tx for impetigo
1st: topic abx (fusidic acid or mupirocin) 2nd: oral abx (flucloxacillin)
148
usual cause of itchy rash which is limited to just the hands
contact dermatitis
149
which condition causes target lesions and was is the most common cause of this condition
erythema multiforme HSV
150
where do psoriasis plaques most commonly appear
extensor surfaces of elbows and knees, scalp
151
pt develops scaly rash after finishing his GCA (giant cell arteritis) Tx diagnosis?
psoriasis (withdrawal from steroids can cause psoriasis)
152
what is Henoch-Schönlein purpura or HSP also known as
IgA vasculitis
153
which condition has a triad of purpura (red blots due to bleeding under skin), arthritis and abdo pain (can also have haemoptysIs)
IgA vasculitis aka HSP
154
when should topical corticosteroids be prescribed or atopic eczema
when the pruritic is severe enough to cause excoriations
155
which medication would you prescribe to a pt with primary biliary cirrhosis to relieve their pruritis
cholestyramine
156
features of scarlet fever
strawberry togue white patches on swollen tonsils red throat swollen lymph nodes fever headache rash
157
common causes of rash on extensor surface
psoriasis dermatitis herpetiformis erythema multiform some types of eczema (atopic eczema in infants, children is on flexures)
158
when should methotrexate not be used for psoriasis
pregnancy
159
what must be avoided whilst taking methotrexate for psoriasis
alchohol
160
side effects of methotrexate
myelosuppression, pulmonary fibrosis and liver fibrosis
161
when is phototherapy used for psoriasis
when the disease is extensive and non-responsive to topical therapies
162
what does haemosiderin deposition look like and what is it suggestive of
patch of darker skin eg brown suggests venous insufficiency
163
which type of white blood cell is associated with contact dermatitis
T lymphocytes
164
which antibody is most likely to be found in SLE, and which antibody is used to diagnose LSE
Anti-nuclear antibody (ANA) = most common Anti-dsDNA antibody = most specific --> sue for diagnosis
165
which condition has Anti-cyclic citrullinated peptide (anti-CCP) antibody
rheumatoid arthirits
166
which condition has Anti-cardiolipin antibody
antiphospholipid syndrome
167
how does erythema multiform rash spread across the body
starts on the palms/soles and then spreads out
168
what type of medication is methotrexate
an anti-folate medication, hence inhibiting the synthesis of DNA and inducing immunosuppression
169
pyoderma gangrenosum vs SJS
both cause blistering lesions pyoderma is typically located to one region eg legs SJS affects widespread area and mucosal membranes eg mouth/lips
170
"erythema of the cheeks that spares the nasolabial folds" likely diagnosis?
SLE
171
Ix for SLE
serum autoantibodies - anti dsDNA
172
Nikolsky's sign and which condition it is seen in
a rash that peels when pressure is applied SJS
173
main features of SJS
blistering rash a rash that peels when pressure is applied (Nikolsky's sign) mucosal ulceration prodromal flu like illness
174
features of SLE
malar rash discoid lupus erythematosus photosensitivity alopecia Subacute Cutaneous Lupus Erythematosus - lesions triggered by UV exposure ulcers/vasculitis myalgia arthralgia
175
Tx for pyoderma gangrensosum
1st line: prednisolone (oral or topical) and line: immunosuppressants
176
which STI can cause erythema nodosum
chalmydia
177
first line Tx for pts with venous insufficiency
compression bandaging
178
how does sunlight affect SLE vs psoriasis
worsens SLE - Discoid lupus erythematosus is the development of red scaling plaques in sun exposed areas of skin improves plaque psoriasis
179
what is used to confirm diagnosis of SJS
skin biopsy
180
which auto antibodies could be present in a pt with dermatitis herpetiformis
Anti-tissue transglutaminase (anti-TTG) antibodies --> underlying diagnosis of coeliac disease
181
what is another word for athletes foot
tinea pedis
182
management of dermatitis herpetiformis
dapsone (antibiotic) as well as maintaining glute free diet to manage the cause - coeliac disease
183
On examination there is a large, erythematous, scaly patch across 3 toes and part of the dorsum of his left foot. There is an area of central clearing and the outer edge appears most inflamed. diagnosis?
tinea pedis / athletes foot