Derm Flashcards
Crusted scabies in patient with HIV
Norwegian scabies… extremely infectious
Isolate. Oral Ivermectin
Dermatitis herpetiformis
Intensely itchy rash on buttocks and top of thigh, assx w coeliac
If gluten free diet doesn’t resolve, can use dapsone with relief of itch within a few days
Oral and potent steroids are used second line
Chickenpox exposure management in pregnancy
Give immunoglobulin if all of
- Significant exposure
- Increased risk of severe reaction - immunosuppressed, neonates or pregnant
- No antibodies
- Rash not already developed
In <20 week preg if they’re not immune, give VZIG asap if within 10 days after exposure
if > 20 weeks and not immune then either VZIG or antivirals (aciclovir or valaciclovir) should be given days 7 to 14 after exposure
> 20 weeks and gets it, then oral aciclovir. Under 20 than consider with caution
salmon-pink, maculopapular rash
Adult onset Stills disease
feat: Arthralgia, pyrexia, Elevated ferritin
Target lesions
Erythema multiforme
Most commonly caused by herpes simplex virus
Followed by Mycoplasma pneumoniae
Patient with end stage renal failure, raised calcium and PTH,painful necrotic skin lesions. What are they?
Calciphylaxis
.,.deposition of calcium within arterioles causing microvascular occlusion and necrosis of the supplied tissue
Warfarin is contraindicated
confirmed on skin biopsy. PTH is sensitive but not specific for calciphylaxis
Tense fluid filled blisters. Management?
Bullous pemphigoid: PO steroids
Young patient with hypothyroidism presents with round bald patches on scalp
Diagnosis and management
Alopecia areata
Autoimmune, triggered by viral
Monitor… Half get spontaneous regrowth in months
Can sometimes give topical steroids, dithranol, triamcinolone acetonide injections
Non healing sterile (culture negative) ulcer
Diagnosis
Pyoderma granulosum
Painful,assx with RA
Pred 60mg OD usually resolves it
Most common trigger of erythema Multiforme
Hsv in ~50%
target lesions, initially seen on the back of the hands / feet before spreading to the torso
next most common mycoplasma
Management for bullous pemphigoid
Derm ref for biopsy
- immunofluorescence shows IgG and C3 at the dermoepidermal junction
Oral corticosteroids, usually heal without scarring
11mm eryhrmatous papule with minimally everted edges, slight scale, no telangiectasia
SCC
Can be side effect of treatment for melanoma w vemurafenib paradoxically
Difference between birthmark that is from birth Vs adolescence
Aka epidermal naevi
Adolescence is more like to have linear pattern
Management of actinic keratosis
small, crusty or scaly, lesions … pink, red, brown or the same colour as the skin on exposed areas
fluorouracil cream: typically a 2 to 3 week course.
Patient presents w white patch on the side of the tongue with a corrugated appearance. Cannot be scraped off
Oral hairy leukoplakia
Ebv in HIV; AIDS defining
Benign
best Tx is antiretrovirals, resolve as CD4 goes up
velvety hyperpigmented skin in axilla is called ? and associated with?
acanthosis nigricans
gastric Ca, obesity, insulin resistance, hypothyroidism
Crohn’s stoma presents with soreness
well-demarcated, full-thickness skin ulceration around stoma. A little slough and Punched-out appearance w violaceous border
Mx
pyoderma gangrenosum
- a recognised complication of Crohn’s. and commonly involves peristomal skin ?Koebner phenomenon.
PO prednisolone
skin conditions w reactive arthritis
Urethritis Circinate balanitis (painless vesicles on the coronal margin of the prepuce) Keratoderma blenorrhagica (waxy yellow/brown papules on palms and soles)
painful oral ulceration, flaccid blisters and erosions
diagnosis and what investigation?
pemphigus vulgaris
Ix: direct immunofluorescence of skin
Tx steroids
pemphigus vulgaris investigation to diagnosis
Direct immunofluorescence of skin
two month hx of 1cm, firm keratotic nodule on the back of his right hand, BG of renal transplant
sun-exposed, rapid growing, immunosuppressed,
SCC
excise and histology
what causes pityriasis versicolor
the yeast Malassezia furfur
what dressing do you use for ulcers?
Hydrocolloid dressings
or Antibacterial and silver-impregnated if local infection
Alginate dressings exudative wounds
Dressings used w exudative wounds
Alginate dressings
or Antibacterial and silver-impregnated if local infection
lace-like purplish mottled skin appearance. Causes?
livedo reticularis - SLE, Polyarteritis nodosa, antiphos syndrome, chol embolism, Amantadine (PD drug) SE
malar rash and arthralgia
ANA positive , dsDNA negative
Drug-induced lupus
May have anti-histone antibodies ( 80-90%)
Macpap rash on palms and soles
Diarrhoea
Post liver transplant
Graft Vs host
pregnant
penetrating injury then small red/brown spot
then raised, red/brown lesion, spherical in shape
Pyogenic granuloma
preg is a risk factor
often resolve spontaneously post-partum
necrobiosis lipoidica diabeticorum management
topical steroids
painless rash on shins typically in diabetics
pt w T-cell cutaenous lymphoma develops pruritis, erythroderma typically affecting the palms, soles and face,
Sezary syndrome
Coumarin skin necrosis mechanism
when first started, biosynthesis of protein C is reduced
…leading to temporary PROcoagulant state
Can be avoided by bridging w heparin
patient on long term 20mg Pred develops chickenpox. MAnagement
> 14d 20mg pred is immunosuppressed or >7d 40mg
so treat w IV aciclovir
NSAIDs may increase risk of secondary bacterial infection
Rash in Microscopic polyangiitis
palpable purpura
superimposed worsening erythema and signif pain following chickenpox infection… what cause?
Invasive group A Streptococcus, a β-haemolytic Streptococcus, has been implicated as the cause for necrotizing fasciitis in patients with chickenpox.
person w Crohn’s develops non-melanoma skin cancer.. why?
Azathioprine increased risk of non-melanoma skin cancer
Patient with end stage renal failure, raised calcium and PTH, painful necrotic skin lesions. What test to confirm diagnosis?
Calciphylaxis, confirmed on skin biopsy. PTH is sensitive but not specific for calciphylaxis
Calciphylaxis prognosis
mortality rate associated with calciphylaxis is as high as 60–80% (!)
Better if distal lesions, worse if proximal
pt notices a ‘slate-grey’ appearance after starting a med
Amiodarone
What is positive Nikolsky’s sign?
the appearance of epidermis separating with mild lateral pressure in toxic epidermal necrolysis and Pemphigus vulgaris
Treatment for guttate psoriasis
Self resolve in 2-3 months but can use UVB therapy
Can do tonsillectomy if recurrent
(Tonsillitis is a common streptococcal inf, which can trigger guttate psoriasis)
diagnosis for symmetrical erythematous lesions on shins with shiney orange peel texture
pretibial myxoedema (seen in Graves)
Old burn or scar… Patient presents with painless ulcerated lesion.. what is it?
SCC in 80% of cases. And is more dangerous -likely to metastasise
Small blisters on the palms and soles
Pruritic, sometimes burning sensation
Diagnosis
Pompholyx…AKA Dyshidrosis
Type of eczema often triggered by hot climates.
Cold compress, emollients, topical steroids… But quite resistant to treatment
Treatment for keloid scar
Triamcinolone (topical steroids) if early
Patient develops oval erythematous plaque then generalised pruritic rash. Diagnosis and what virus is linked to it?
Pityriasis rosea
Herpes hominis virus 7 (HHV-7) is thought to play a role in the aetiology
self-limiting - usually disappears after 6-12 weeks
Patient with herpes… What sign indicates ocular involvement is likely?
Vesicles on the tip of the nose, or vesicles on the side of the nose…Hutchinson’s sign
- strongly predictive for ocular involvement…
pinpoint petechial ‘blueberry muffin’ skin lesions
congenital cytomegalovirus
Small, red-brown macules that may coalesce into larger patches with sharp borders; may be asymptomatic or pruritic; fluoresces coral-red on Wood lamp examination
Erythrasma
Overgrowth of diphtheroid Corynebacterium minutissimum, often due to humid environments
Coral red florescence on Wood’s light
Topical miconazole
(Acnathosis nigracans is: Hyperpigmentation with velvety, thickened skin, predominantly on posterior neck and body folds)
photosensitive rash with blistering and skin fragility on the face and dorsal aspect of hands
Porphyria cutanea tarda
inherited defect in uroporphyrinogen decarboxylase
OR caused by hepatocyte damage e.g. alcohol, hepatitis C, oestrogen
urine: elevated uroporphyrinogen and pink fluorescence of urine under Wood’s lamp
Mx: chloroquine
Skin biopsy of tender nodules on legs
Erythema nodosum - neutrophil panniculitis
patient had chickenpox recently then presents w painful rash, hypotensive, fever, AKI
Diagnosis / management
Chickenpox is a risk factor for invasive group A streptococcal soft tissue infections including necrotising fasciitis
NSAIDs may increase the risk of developing this
Tx: Surgery
