Dermatology Flashcards
SJS vs TEN?
SJS: <10% skin involvement
TEN: >30%
Aetiology SJS/TEN?
secondary to drug reaction (Never Press Skin As It Can Peel) NSAIDS Phenytoin Sulphonamides Allopurinol IVIG Carbamazepine Penicillin
S/S SJS/ten?
Scalded skin appearance over an extensive area
systemic upset
Ix SJS/TEN?
Nikolsky’s sign positive (epidermis separates with mild lateral pressure)
Mx SJS/TEN?
stop precipitating factor
ITU
IVIG
Immunosuppression (ciclosporin, cyclophosphamide) plasmapheresis
What is erythroderma?
any rash involving >95% of the body
causes of erythroderma?
eczema psoriasis drugs (gold) lymphoma, leukaemia idiopathic
complications of erythroderma
dehydration
high output cardiac failure
infection
what is seborrhoeic dermatitis?
chronic dermatitis caused by an inflammatory reaction related to a proliferation of a normal skin fungus (malassezia furfur)
who does seborrhoeaic dermatitis commonly affect?
immunosuppression (HIV)
Neurological (PD, Down’s, epilepsy)
Alcoholic pancreatitis
S/S of seborrhoeic dermatitis?
Eczematous lesions on sebum rich areas (dandruff, periorbital, auricular and nasolabial folds)
may present with otitis externa, blepharitis
Mx seborrhoeic dermatitis?
Scalp disease:
1st line: zinc pyrithione (‘head and shoulders’) and tar (‘neutrogena T/Gel’)
2nd line: ketoconazole
alternatives: selenium sulphide, topical corticosteroid
Face and body disease: topical antifungals (ketoconazole) topical steroids (short periods)
What is impetigo?
common skin infection caused by staph aureus, streptococcus pneumonia
S/S impetigo?
golden yellow crusted appearance
Management of impetigo?
hygiene meaures
Localised non-bulbous: topical H2O2 cream (peroxide), topical fusidic acid antibiotic
widespread non bullous; oral flucloxacillin OR topical fusidic acid 2% antibiotic
bullous systemically unwell: oral flucloxacillin
School exclusion until lesions crusted over OR 48 hour after Abx started
which bacterium causes acne vulgarisms?
increased sebum and blocked glands
propionibacterium acnes
20% of adolescents have moderate to severe acne
what are the levels of acne?
comedones (follicles impacted and distended by incompletely desquamated keratinocytes and sebum) - open or closed
papules and pustles
nodulocystic and scarring
S.S of acne vulgaris?
greasy face
comedones, papules, pustules, nodules
psychological impact, low self esteem
when do you do a dermatologist referral for acne?
nodulocystic acne/scarring severe form (acne conglobata, acne fulminano) severe psychological distress diagnostic uncertainty failing to respond to medications
Acne management?
Conservative:
- avoid over cleaning skin (2x day with gentle soap_
- use emollients and cleansers (non-comdeogenic)
- face : avoid picking and squeezing (scars)
meds:
Mild: 1st: topical retinoid and/or benzoyl peroxide +/-topical Abx /2nd line: azelaic acid
moderate: oral Abx (max 3m) + BPO + retinoid OR cocp + BPO/retinoid
severe: dermatologist referral - oral isotretinoin, once cleared maintain with topical retinoids or azelaic acid
Support; NHS choices leaflet, british association of dermatologists
Which Abx are preferred for acne?
topical: clindamycin 1%
oral: 1st line tetracyclines (lymecycline, doxycycline), 2nd line macrolides (erythromycin)
What are the S/S of acne rosacea?
1: flushing
2: asymmetrical rash of nose, cheeks, forehead and telangiectasia
3: persistent pustulopapular erythema (rhinopehyma, ocular involvement- blepharitis, photosensitivity)
commonly worsens with alcohol
Acne vulgaris vs acne rosacea?
vulgaris = young, comedones rosacea = middle-aged, flushing, symmetry
Management of acne rosacea?
mild/moderate: topical metronidazole
severe: oral tetracycline (oxytetracycline)
flushing, limited telangiectasia: topical brimonidine gel
adjuncts: high factor sunscreen, camouflage creams, laser therapy (telangiectasia)
What is hidradenitis suppurativa?
chronic inflammatory occlusion of folliculopilosebaceous units that obstructs the porcine glands and prevents keratinocytes from properly shedding from the follicular epithelium
RF for hidradenitis suppurativa?
FHx
obesity, DM, PCOS
Smoking
Mechanical skin stretching
S/s hidradenitis suppurativa?
recurrent build in intertriginous areas (axilla, neck, thights, inguinal)
coalesce of nodules can result in plaques, sinus tracts and rope like scarring
Management of hidradenitis suppurativa?
conservative: good hygiene and loose fitting clothing
smoking cessation
WL
medical:
acute - steroids,flucloxacillin +/- surgical incision and drainage
chronic - clindamycin (topical), lymecycline/clindamycin/rifampicin PO
What is pityriasis versicolor?
caused by malassezia furfur
common fungal infection that causes small patches of skin to become scaly and discoloured
What are the S/S of pityriasis versicolor?
trunk affected - hypopigmneted patches and scale, mild pruritic, follows a suntan
triggers for pityriasis versicolor?
immunosuppression, malnutrition, Cushing’s
Mx pityriasis versicolor?
topical ketoconazole
pityriasis versicolor vs vitiligo?
vitiligo affects peripheries and is much more confluent
what are the S/S of vitiligo?
well demarcated, depigmented skin patches
Vitiligo associations?
T1DM,Addisons, autoimmune thyroid, pernicious anaemia, alopecia areata
Mx vitiligo?
sunblock
camouflage makeup
topical corticosteroids (reverse changes if applied early)
what causes pityriasis rosea?
HHV-7
S/S of pityriasis rosea?
1: recent viral infection -> herald patch (usually on trunk)
2: erythematous oval scaly patches (running parallel to the line of Langer ‘fir tree appearance’)
Mx: self limiting (6-12w)
What are the types of psoriasis?
plaque
guttte
pustular
flexural
what are the features plaque psoriasis?
most common; well demarcated red, scaly patches affecting extensors
what are the features of guttate psoriasis?
streptococcal infection; multiple transient, red, teardrop lesions
no mx required
what are the features of pustular psoriasis?
palms and soles of feet
what are the features of flexural psoriasis?
skin is smooth in contrast to plaque psoriasis
Exacerbating factors for psoriasis?
trauma
ETOH
drugs (beta blockers, lithium, antimalarials, NSAIDs, ACEi, infliximab)
withdrawal of systemic steroids
infection (strep infection may trigger guttate psoriasis subtype only)
Management of chronic psoriasis plaque?
corticosteroids:
potent - use max 8w at a time
very potent - use max 4w at a time
4w breaks between courses of topical corticosteroids
SE: skin atrophy, striae, rebound symptoms
vitamin D analogue info
reduced scaling and thickness but no effect erythema
can be used long term
avoid in pregnancy
Management of psoriasis in primary care?
1st line (4w trial): OM corticosteroid (potent) and ON vitamin D analogue 2nd line (after 8 w): OM corticosteroid (potent) and BD vitamin D analogue 3rd line: BD corticosteroid (4w potent) or coal tar (OD or BD)
Adjunct: emollients (reduce scale loss, reduce pruritic)
Alternative: short acting dithranol (wash off after 30m)
Management of psoriasis in secondary care?
phototherapy (P-UVB, 3x/Week) or photochemotherapy (P-UVA + psoralen)
Systemic medications: 1st methotrexate; other: ciclosporin, retinoids, infliximab, etanercept, adalimumab
What is eczema?
chronic, relapsing, inflammatory skin condition characterised by an itchy red rash, commonly on FLEXURES
Eczema triggers?
irritants, contact allergens, extremes of temperature (worse in winter), abrasive fabrics, sweating
Signs & symptoms of eczema
infant: face and trunk
older child: extensors of limbs
young adult: localises to the flexures
Investigations eczema?
consider food allergies - blood or skin prick testing
consider contact dermatitis - patch testing
management of eczema?
flared - treat ASAP and for 24h post symptoms
What is the steroid ladder?
Help every busy dermatologist Hydrocortisone Euvomate (clobetason) Betnovate (betamethasone) (elocon - mometasone) Dermovate (clobetasol)
How is mild eczema managed?
emollients
mild potency topical steroids (hydrocortisone)
How is moderate eczema managed?
emollients
moderate potency topical corticosteroids
topical calcineurin inhibitors
bandages
How is severe eczema managed?
emollients potent topical corticosteroids systemic therapy phototherapy topical calcineurin inhibitors bandages
antihistamines (non sedating vs sedating at night)
How is infected eczema managed?
skin swab and culture oral flucloxacillin (erythromycin if pen allergic)
how is eczema herpeticum managed?
oral acyclovir
if around eyes same day referral to ophthal
health education (emergency = rapidly worsening eczema, clustered blisters, punched out erosions)
N.b. eczema herpeticum can look similar to impetigo so treat for both empirically with oral/IV Abx and oral/IV acyclovir
what are the directions for applying emollient?
apply to whole body and wait 30 mins before applying steroid creams
apply with Finger tip units (FTU)
What is 1 FTU?
Palm of hand
elbows
knees
give and example of a mild and moderate/severe calcineurin inhibitors?
mild/mod: pimecrolimus
mod/severe: tacrolimus
What is tinea?
fungal infection where dermatophyte fungi incase dead keratinous structure (trichophytum rubrum)
S/S of tinea?
ringed appearance +/- keri on (severe inflamed ringworm patch), red or silver rash
Tinea capitis - scalp
Tinea pedis - feet
Mx tinea?
Tinea capitis:
oral anti fungal (e.g. griseofulvin or terbinafine)
Other tinea:
mild: topical antifungals e.g. topical terbinafine, clotrimazole, miconazole
moderate: hydrocortisone 1% cream
severe: oral antifungals (1st line oral terbinafine, 2nd line: oral itraconazole
What advice should be given for managing tinea?
very contagious wear loose fitting cotton clothing dry throroughly after washing do not share towels no need for school exclusion wash affected areas of skin daily avoid scratching wash clothes and bed linen frequently
what is shingles?
Herpes zoster infection - reactivation of VZV
RFs for shingles?
Increasing age
Immunosuppression (HIV 15x more common, steroids, chemotherapy)
S/S shingles?
prodromal period (burning over affected dermatome for 2-3 days+/- fever, headache, lethargy rash (erythematous, macular rash over the affected dermatome - vesicular)
Management of shingles?
infectious until vesicles have crusted over
analgesia (paracetamol and NSAIDs), neuropathic agents, oral corticosteroids
Antivirals (PO acyclovir) (<72h, >50yo)
Complications of shingles?
- post-herpetic neuralgia (5-30% of patients depending on age)
- herpes zoster ophthalmicus
- herpes zoster optics (Ramsay-hunt syndrome)
what is actinic keratosis?
pre-malignant skin condition for SCC
S/S actinic keratosis?
small, crusty or scaly, lesions, sun-exposed areas
Management actinic keratosis?
GP if simple, urgent 2WW dermatology if immunosuppressed:
Fluorouracil cream (2-3w) +/- topical hydrocortisone
Topical diclofenac (mild AKs)
Topical imiquimod
Cryotherapy
Curettage and cautery
what is keratocanthoma?
pre-malignant skin condition for SCC
has rapid growth phase
S/S keratocanthoma?
small, dome shaped papule - crater filled with keratin
Mx keratocanthoma?
excision
Aetiology of fungal nail infections?
dermatophytes
Ix fungal nail infection?
nail clipping MC&S
Mx of fungal nail?
patient choice (must be confirmed by MCS before treatment)
- nil: asymptomatic and patient not bothered by appearance
- dermatophyte infection: 1st: PO terbinafine, 2nd PO itraconazole (finger 6w-3m, toe 3m-6m)
- candida infection: mild = topical anti fungal (amorolfine), severe = oral itraconazole (12w)
what must be checked before prescribing terbinafine/itraconazole?
LFTs
What are the S/S of lichen plants?
Ps Purple pruritic papular polygonal rash on flexors
Wickham’s striae (thin white lines in mouth)
Causes of lichen planus?
gold
quinine
thiazides
Management of lichen planus?
body -> topical steroids (clobetasone butyrate)
oral -> benzydamine mouthwash
xtensive lichen planus may require oral steroids or immunosuppression
S/S lichen sclerosus?
itchy white spots typically seen on the vulva of elderly women
mx lichen sclerosus?
1st (3m): clobetasol propinate
2nd: tacrolimus + biopsy
what is the cause of cellulitis?
streptococcus pyogenes OR staphylococcus aureus
S/S of cellulitis?
poorly demarcated deep skin infection
what is the Eron classification for cellulitis?
I: no signs of systemic toxicity, person has no uncontrolled co-morbidities
II: systemically unwell or systemically well but with a co-morbidity
III: significant systemic upset such as acute confusion, tachycardia, tachypnoea, hypotension or unstable co-morbidities
IV: sepsis, necrotising fasciitis
Management of cellulitis?
mild/moderate: flucloxicillin (alt: clarithromycin, erythromycin, doxycycline)
severe: co-amoxiclav, cefuroxime, clindamycin, ceftriaxone
What is the cause of erysipelas?
streptococcus pyogenes (group A haemolytic strep)
S/S erysipelas?
well-demarcated superficial skin infection
Mx erysipelas?
flucloxacillin
Cause of erythrasma?
corynebacterium minutissimum
S/S erythrasma?
asymptomatic flat scaly pink/brown rash in axilla/skin crease
Ix erythrasma?
Woods slit lamp, coral red fluorescence
Mx erythrasma?
topical miconazole (local) or PO erythromycin
What are the common shin conditions?
erythema nodosum
pretibial myoxedema
pyoderma gangrenosum
necrobiosis lipodica diabeticorum
Causes of erythema nodosum ?
streptococcal infections, TB, brucellosis sarcoidosis IBD drugs (penicillins, sulphonamides, COCP) malignancy
S/S erythema nodosum?
symmetrical erythematous tender nodules which heal without scaring
S/S pretibial myxoedema?
symmetrical erythematous lesions seen in Graves
shiny orange peel skin
Causes of pyoderma gangrenosum?
idiopathic (50%)
IBD
Connective tissue disorders and myeloproliferative disorders
S/S pyoderma gangrenosum?
1st - small red papule
2nd - later deep red, necrotic ulcers with a violaceous border
Mx pyoderma gangrenosum?
oral steroids
What necrobiosis lipoidica diabeticorum associated with?
telangiectasia, diabetes
S/S necrobiosis lipoidica diabeticorum?
shiny, painless areas of yellow/red skin
seen on diabetics
What is bullous pemphigoid ?
Abs against BM (dermoepidermal junction)
S/S bullous pemphigoid?
itchy tense blisters, no oral involvement
Mx bullous pemphigoid?
oral corticosteroids
what is pemphigus vulgaris?
Abs against desmosomes
S/S pemphigus vulgaris?
flaccid blisters
oral involvement
what areas does erythema nodosum affect?
legs, knees, arms
causes erythema nodosum?
SORE SHINS Streptococci, mycoplasma, EBV OCP Rickettsia Eponymous (Behcets)
Sulphonamides, penicillin Hansens (leprosy) IBD/idiopathic Non Hodgkin's Sarcoidosis/TB
What causes erythema multiforme?
a hypersensitivity reaction Infection (90%): HSV> mycoplasma Drugs (<10%): barbiturates, NSAIDs, penicillin, sulphonamides, sulphonylurea, nitrofurantoin SJS/TEN SLE Sarcoid malignancy
what causes erythema ab igne?
chronic exposure to heat (hot water bottle, open fire)
what does erythema ab igne increase likelihood of?
SCC
what causes erythema chronicum migrans?
borrelia burgdorferi (spirochete, Ixodes tick)
S/S erythema chronicum migrans?
localised (rash, flu-illness), early disseminated (arthritis, carditis), late disseminated (chronic disorders)
what causes erythema marginatum?
rheumatic fever (GAS)
S/S erythema marginatum?
CASES FRAPP carditis arthritis syndenhams chorea erythema marginatum SC nodules;
fever raised ESR arthralgia prolonged PR previous rheumatic fever
what causes migratory necrolytic erythema?
glucagonoma
What is a pyogenic granuloma?
a reactive proliferation of capillary blood vessels - usually follow trauma
self-limiting
what is a sebaceous cyst?
epithelial lined cavity containing keratin
- encompasses epidermoid and pilar cysts
where are sebaceous cysts most common?
scalp ear face back upper arm
what are the most common penile skin disorders?
lichen sclerosis
zoon’s balanitis
circinate balanitis
erythroplasia of queyrat
what is lichen sclerosis of penis?
tight white ring around tip of foreskin + phimosis
what is zoons balanitis?
unknown origin; secondary to lichen sclerosis/EOQ
what are the S/s of zoons balanitis?
orange red lesions + pin point red spots
what is circinate balanitis?
balanitis in reactive arthritis
what are the S/S of circinate balanitis?
well demarcated erythematous plaque with a ragged white border
What is erythroplasia of Queyrat?
in situ SCC
single or multiple plaques with a red velvety appearance
what is the management of athletes foot?
1st: topical antifungals (ie clotrimaole, imidazole)
2nd oral antifungals ie PO terbinafine
What is the inheritance pattern for hereditary haemorrhagic telangiectasia/Osler-Weber-Rendu?
AD
What are the S/S HHT?
4 diagnostic criteria (>=3 for diagnosis)
- epistaxis
- telangiectasia (lips, oral cavity, finers, nose)
- visceral lesions (GI +/- anaemia, AVM pulmonary/hepatic/spinal/cerebral)
- FHx (1st degree)
What does granuloma annulare looks like?
papular lesions
slightly hyperpigmented and depressed centrally
Where does granuloma annulare occur?
dorsal surfaces of the hands/feet
extensor aspects of the arms and legs
what causes scabies?
mite sarcoptes scabiei
where does the mite lay its eggs in scabies?
stratum corneum
what causes the intense pruritis associated with scabies?
delayed type IV hypersensitivity reaction to mites/eggs which occurs at about 30 d
What are the S/S of scabies?
widespread pruritis
linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrists
pruritic can persist for up to 6 weeks post treatment
Mx scabies?
permethrin 5% (2x OW full body treatments; wash off after 8-12 hours) + treat all household/close contacts
2nd line: malathion, wash off after 24 h
what is the Mx for head lice?
malathion, wash off after 24 h
What is a dermatofibroma?
benign overgrowth of dermal fibroblasts
often caused by previous trauma
S/S dermatofibroma?
F>M
firm
woody
solitary firm papule or nodule, typically on a limb
typically around 5-10mm in size
overlying skin dimples on pinching the lesion
Mx dermatofibroma?
nil
what is a neurofibroma?
benign overgrowth of nerves?
Aetiology of seborrhoeic keratosis?
hyperkeratosis (thickened stratum corneum)
acanthosis (thickened stratum spinosum)
hyperplasia of basal cells
S/S seb K?
greasy
stuck on
cauliflower like growth
What is sudden onset multiple seb k called?
Leser Trelat sign (?underlying malignancy)
what may cause an intradermal lump?
(within dermis)
dermatofibroma
epidermal cyst
intradermal naevus
what may cause subcutaneous lump ?
(below the dermis) neurofibroma panniculitis lipoma ganglion lymph nodes
Features of a pyogenic granuloma?
most common sites are head/neck, upper trunk and hands. Lesions in the oral mucosa are common in pregnancy
initially small red/brown spot
rapidly progress within days to weeks forming raised, red/brown lesions which are often spherical in shape
the lesions may bleed profusely or ulcerate
Management of pyogenic granuloma?
lesions associated with pregnancy often resolve spontaneously post-partum
other lesions usually persist. Removal methods include curettage and cauterisation, cryotherapy, excision
What are the side effects of roaccutane?
dryness, teratogenic -must be on 2 forms of contraception raised TGs hair thinning intracranial HTN photosensitivity low mood/suicidal ideation
what is the commonest skin disorder in pregnancy?
atopic eruption of pregnancy
What is polymorphic eruption of pregnancy?
pruritic condition associated with last trimester
lesions often first appear in abdominal striae
management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
what is pemphigoid gestationis?
pruritic blistering lesions
often develop in peri-umbilical region, later spreading to the trunk, back, buttocks and arms
usually presents 2nd or 3rd trimester and is rarely seen in the first pregnancy
oral corticosteroids are usually required
what are the features of erythema multiforme?
target lesions
initially seen on the back of the hands / feet before spreading to the torso
upper limbs are more commonly affected than the lower limbs
pruritus is occasionally seen and is usually mild
what is erythema multiforme major?
severe form of erythema multiforme
severe form, erythema multiforme major is associated with mucosal involvement ie mouth
What is alopecia areata?
autoimmune condition causing localised, well demarcated patches of hair loss. At the edge of the hair loss, there may be small, broken ‘exclamation mark’ hairs
what is the prognosis of alopecia areata?
Hair will regrow in 50% of patients by 1 year, and in 80-90% eventually
Treatment options for alopecia areata
topical or intralesional corticosteroids topical minoxidil phototherapy dithranol contact immunotherapy wigs
causes of erythema nodosum?
NODOSUM no - idiopathic d - drugs o - oral contraceptive/pregnancy s - sarcoid/tb u - ulcerative colitis/crohn's/behcets m - microbiology (strep,mycoplasma, EBV)
Causes of acanthosis nigricans?
type 2 diabetes mellitus gastrointestinal cancer obesity polycystic ovarian syndrome acromegaly Cushing's disease hypothyroidism familial Prader-Willi syndrome drugs - combined oral contraceptive pill - nicotinic acid
What are the features of BCC
The most common type is nodular BCC
sun-exposed sites, especially the head and neck account for the majority of lesions
initially a pearly, flesh-coloured papule with telangiectasia
may later ulcerate leaving a central ‘crater’
Mx BCC?
surgical removal curettage cryotherapy topical cream: imiquimod, fluorouracil radiotherapy
Where does acral lentiginous melanoma occur?
occurs in areas not exposed to the sun such as soles of feet and palms
Nails, palms or soles, African Americans or Asians
Features of melanoma?
size > 5mm, irregular border, poorly defined borders, irregular pigment network and background erythema
What are the types of melanoma?
superficial spreading
nodular
lentigo maligna
acral lentiginous melanoma
features of superficial spreading melanoma?
70% cases
Arms, legs, back and chest, young people
A growing moles with diagnostic features
features of nodular melanoma?
Sun exposed skin, middle-aged people
Red or black lump or lump which bleeds or oozes
most aggressive
features of lentigo maligna?
Chronically sun-exposed skin, older people
A growing mole with diagnostic
what are the main diagnostic features of melanoma?
Change in size
Change in shape
Change in colour
Secondary features (minor criteria) Diameter >= 7mm Inflammation Oozing or bleeding Altered sensation
Mx melanoma?
Suspicious lesions should undergo excision biopsy. The lesion should be removed in completely as incision biopsy can make subsequent histopathological assessment difficult.
Once the diagnosis is confirmed the pathology report should be reviewed to determine whether further re-excision of margins is required
What is melanoma excision of margins related to?
Breslow thickness
Lesions 0-1mm thick 1cm
Lesions 1-2mm thick 1- 2cm (Depending upon site and pathological features)
Lesions 2-4mm thick 2-3 cm (Depending upon site and pathological features)
Lesions >4 mm thick 3cm
What is Koebners phenomenon?
where lesions are seen at the site of injuries. It is seen in: psoriasis vitiligo warts lichen planus lichen sclerosus molluscum contagiosum
