dermatology Flashcards
therapeutic ladder
irritant avoidance emollients topical treatments phototherapy systemic therapy eg immunosuppression
commonest bacteria found on face
staph. aureus
80% of people with acne have it on their skin
apple jelly appearance
cutaneous TB
herpes simplex -virus?
HSV 1
chicken pox -virus?
varicella zoster virus
one handed eczema
fungal infection
therapeutic acne
- topicals
- tetracycline abx
- retinoid: isotretanoin (only prescribed in hospital)
acne excorrie
mild acne but excess picking
treat acne + treat psychological aspect
atrophic ice pick scarring
acne scarring
atopy triad
allergic rhinitis
athma
eczema
eczema - areas in different ages
onset in infancy on dace
childhood: elbow and knee flexures
adult: face trunk hands, flexures
widespread herpes simplex with eczema
eczema herpeticum
silvery scale plaques
well defined
scalp
extensor surfaces
psoriasis two peaks of onset nail involvement scalp genital involvement
guttate psoriasis
- small plaques
- can present after streptococcal throat infection
flexural psoriasis - areas
natal cleft
groin
axillae
pustules on hand and feet
doesn’t grow anything on swab
plantarpalmar pustulosis
psoriasis management
topical steroids
phototherapy
systemic: methotrexate
25yrs
1yr hx 3 lumps on lower leg
each lesion is firm, well-circumscribed and measures 3-4mm in diameter
best term to describe this lesion?
papule
nodule
solid elevated lesion developing within the skin >0.5cm
e.g. pyogenic granuloma
papule
circumscribed lesion in skin <0.5cm, solid
macule
entirely flat area within the skin
plaque
slightly elevated but superficial lesion of skin
38yrs
- 4mth hx deeply pigmented lesion on left upper arm
- fair skin and blue eyes
- 1.5cm diameter asymmetrical shape and irregular edge
- dermoscopy and surgical excision confirmed clinical diagnosis
diagnosis?
what feature is the best predictor of prognosis?
- dermoscopy findings
- eye colour
- lesion depth
- lesion diameter
- skin type
malignant melanoma
lesion depth - Breslow thickness
- can only be identified histologically once lesion is excised
vesicle
raised clear fluid filled lesion >0.5cm
bulla
raised clear fluid filled lesion >0.5cm in reaction to insect bites
pustule
pus containing lesion <0.5cm
abscess
localised accumulation of pus in the dermis or subcutaneous tissue
wheal
transient raised lesion due to dermal oedema e.g. urticaria
boil
staphylococcal infection around or within a hair follicle
excoriation
loss of epidermis following trauma
e.g. excoriations in eczema
lichenification
well-defined roughening of skin with accentuation of skin markings. due to chronic rubbing
scales
psoriasis flakes of stratum corner. crust rough surface consisting of dried serum blood bacteria and cellular debris
port wine stain
Sturge weber syndrome
- congenital vascular anomalies
- port wine stain
- brain abnormality called a leptomeningeal angioma
- glaucoma
purpura
red or purple colour due to bleeding into skin or mucous membrane
this does not blanch on pressure
ulcer
loss of epidermis and dermis
fissure
en epidermal crack often due to excess dryness
erythema nodosum
pathology
causes
hypersensitivity response to various stimuli - inflammation of subcutaneous fat
- drugs: penicillin, suphonamides
- group A beta-haemolytic streptococcus
- primary TB
- pregnancy
- sarcoidosis
erythema nodosum presentation
- TENDER erythematous nodular lesions
- resolve within 6 weeks
- leave bruise-like discolouration as they resolve
- resolve without atrophy or scarring - no treatment necessary
erythema multiforme
pathology
causes
limiting inflammatory condition
main cause: herpes simplex virus
- infections
- drugs: penicillin, sulphonamides
erythema multiforme presentation
- target lesions - initially seen on back of hands and feet then torso
- upper limbs> lower limbs
- ring rash - target/bullseye
- cherry red central spot, then pale outer ring then pink outermost ring
- pruritic mild
pyogenic granuloma
pathology
causes
relatively common benign skin lesion actually a haemangioma - trauma - pregnancy - women > men
pyogenic granuloma presentation
- common sites: head/neck, upper trunk, hands - presents at site of trauma
- oral mucose - common in pregnancy
- initially red spot progresses within days to weeks and becomes raised and spherical
- can bleed a lot
pyoderma gangrenosum
presentation
- initially small red papule
- later red necrotic ulcer
- lower limbs
- idiopathic 50%, IBD, rheumatoid
pyoderma gangrenosum
causes
- idiopathic 50%
- IBD
- rheumatoid
- myeloproliferative disorders
- connective tissue disorders
- primary biliary cirrhosis
pyoderma gangrenosum
management
- first line - oral steroids
- immunosuppressive ciclosporin and infliximab in difficult cases
angioedema and anaphylaxis - urticaria
pathology (types) and causes
- urticaria is due to local increase in capillary permeability
- inflammatory mediators released by mast cells
- most are spontaneous or stress triggered, physical stimulus
- acute urticaria <6wks
- chronic urticaria >6wk
- inducible urticaria: tight pyjamas
- contact urticaria: transient swelling and redness e.g. latex allergy
presentation of urticaria
- swelling in superficial dermis - raised
- itchy wheals 48hrs later they fade
chronic urticaria:
- joint pain
- fever
connective tissue disease more likely
investigations for urticaria
- bloods: FBC, CRP, complement IgG
- autoimmune panel
- no use for patch testing
- check for tongue & laryngeal involvement
management - urticaria
- regular antihistamines
- 1st line: CETIRIZINE 10mg TDS
- fexofenadine
+/= montelukast & ranitidine - prednisone for acute flare
- anaphylaxis: adrenaline (0.5ml epipen) + corticosteroids + antihistamines
eczema herpeticum
cause
- serious complication of atopic eczema
- HERPES SIMPLEX 1
- can be facilitated by topical steroids
eczema herpeticum
presentation
- extensive crusted papule
- blisters
- erosions
- fever
- multiple monomorphic vesicles
eczema herpeticum management
- acyclovir PO or IV
- abx for 2ndry bacterial infection
- topical steroids if eczema gets bad
- admission
abx for infection of atopic eczema
erythromycin and clarithromycin
allergic contact dermatitis
what type of reaction
type IV hypersensitivity
allergic contact dermatitis presentation
- localised in area of contact
- hands - latex gloves
- rubber, nickel, preservatives, cosmetics
allergic contact dermatitis management
- remove trigger and allergen
- topical steroids: potent
- antiseptic soak contains potassium permanganate if oozing
- patch testing
- emollients ++
cellulitis
pathology
cause (two bacteria)
- deep subcutaneous tissue
- streptococcus pyogenes
- staph aureus
cellulitis presentation
- erythema
- swelling
- lower legs
- systemic upset
- fever
- pain
- muscle upset
- well demarcated
cellulitis management
- flucloxacillin
- benzylpenicillin
- linezolid
erysipelas
pathology
cause
- acute superficial form of cellulitis - superficial subcutaneous skin and the dermis
- streptococcus
erysipelas presentation
- face common
- rapid onset
- pain
- erythema
- oedema
- skin taught skin
- fever and malaise/ rigors more common
erysipelas management
IV penicillin
analgesia
necrotising fasciitis
pathology
cause
- rapidly spreading infection of deep fascia with secondary tissue necrosis
- group A haemolytic streptococcus
necrotising fasciitis
presentation
- 50% in previously healthy
- severe pain
- erythematous
- blistering and necrotic skin
- systemically unwell with fever and tachycardia
- crepitus
necrotising fasciitis
investigations and management
- x-ray - soft tissue
- urgent referral for surgical debridement
- IV piperacillin and tazosin
- mortality 76%
seborrheic keratosis
pathology and cause
risk factors
benign
- basal cell papilloma. WART
- proliferation of basal cell keratinocytes
- need to rule out melanoma
risk factors:
- old age (80% >50yrs)
seborrheic keratosis
management
reassure - most don’t need treatment
- aldara cream
- cryotherapy
- curettage
seborrheic keratosis
presentation
- asymmetry
- border - notched
- colour - multiple <2
- usually brown
- matt rough surface
- catch on clothes
- may bleed
dermatofibroma
presentation
benign very common - firm elevated dermal nodule - smooth - central white scar - 5-10mm diameter - red/brown - young adults - arms and legs (mostly legs) - hx of trauma - lesions have histiocytes blood vessles and fibrotic changes
dermatofibroma
management
- effudex OD for 4 wks topical
actinic keratosis
presentation
- benign sun-spots
- red pink brown
- scaly and rough
- flat or raised sore and itchy
actinic keratosis
management
- efudex (5% fluorouracil)
- cryotherapy
- curettage under LA
- monitor growth - risk of SCC
lipoma
benign tumours of fat
- soft masses in subcutaneous tissue
- often multiple lesions
- painful
- don’t normally need treatment - harmless
- can be cut out
vascular tumours
benign
- cherry angioma - small red papular vascular lesions
- strawberry naevus in newborns
- pyogenic granuloma
- rapidly developing 2-3wks
- red or weepy crusted nodule
- can bleed a lot
- trauma induced + pregnancy
- young adults & children
rosacea presentation and exacerbating factors
- chronic disorder of pilosebaceous units
- flushing - first symptom
- no comedones
- vascular telangiectasia common
- papulopustular + erythema
- rhinopehyma - red wart like growths on nose
- nose, cheeks, forehead
sunlight can exacerbate
worse with ALCOHOL
ocular rosacea
- dry eyes
- irritation
- redness
- crusting
- itching
- burning
- recurrent infections
rosacea management
mild:
- topical metronidazole (papules, no pustules or plaques)
- topical brimonidine gel (flushing no telangectasia)
severe disease:
- oxytetracycline abx
- daily suncream
- laser - prominent telangiectasia
- rhinophyma needs referral
occular rosacea mx:
- doxycycline abx
psoriasis
pathology, types
chronic inflammatory condition due to hyper proliferation of keratinocytes and inflammatory cell infiltration
types:
- chronic plaque psoriasis - most common - on extensors, sacrum and scalp
- seborrheic
- flexural (body folds)
- pustular psoriasis: palms ans soles
psoriasis precipitating factors
- trauma - koebner phenomenon
- infection
- drugs: beta blockers, lithium, NSAIDs, ACEi, infliximab
- stress
- alcohol
acute psoriasis
acute pustular:
- immediate management
- pustules on erythematous and tender skin
guttate:
- 2ndry to streptococcal infection/sore throat
- raindrop lesions, trunks and limbs
- more common in children and teens
erythrodemic:
- burned looking skin
- peeling like sheets
psoriasis presentation
- well demarcated
- erythematous scaly plaques
- extensors, scalp, sacrum,
- itchy or painful
auspitz sign: scratch and removal of scales –> bleeding) - 50% nail changes - onycholysis
- nail pitting
- 5% –> psoriatic arthritis: DIP, rheumatoid like, psoriatic spondylosis
clinical diagnosis
psoriasis management
lifestyle:
- avoid sun
- reduce alcohol
- reduce BMI
chronic plaque psoriasis:
- 1st line: POTENT TOPICAL STEROID + VIT D OD
- if no improvement after 8 wks: vit D BD alone
- if vit D not effective after 8-12 wks:
- -> coal tar OD
- -> potent topical steroid BD
- if no effect:
- -> calcipotriol + betamethasone OD 4wks
- phototherapy:
- ->UVB: plaque, guttate
- ->PUVA (psoralen): palmoplantar pustulosis
- systemic therapy:
- -> methotrexate
- -> ciclosporin (rapid/short term treatment, in conception, for palmoplantar pustulosis)
- biologics
e. g adalimumab, etanercept
side effects of steroids
- skin atrophy
- striae
- rebound symptoms
- flexures, scalp, face: 1-2 wks/month at a time
- no more than 8 wks at one site at a time
- very potent steroids not >4ks at a time
- NICE recommends 4 week breaks
vitamin D - what does it do and when to avoid
calcitriol
reduces scale and thickness of plaques
avoid in pregnancy
acne vulgaris
causes
precipitating factors
an inflammatory disease of the pilosebaceous follicle
80% are teenagers 13-18
causes:
- inflammation
- bacterial colonisation with propionibacterium acnes (anaerobic rod resilient to penicillin)
- abnormal follicular keratinisation
- increased sebum production
precipitating factors
- PCOS
- trauma-Koebner phenomenon
- infection
- durgs - ciclosporin, lithium, tamoxifen
- stress
- alcohol
acne
clinical features
mild, moderate and severe
mild: - non-inflammatory lesions - open and closed comedones - papules <5mm sparse lesions
moderate:
- pustules and papules
severe:
- nodular acne
- cystic
- pitting
- pin-roll scarring, ice pick scars, hypertrophic
- unusual sites e.g. trunk, back
- keloid scarring
- lots of lesions >100
acne management - mild moderate, severe
mild:
- single topical exfoliants: tea tree oil
- keratolytics: benzyl-peroxide, salicylic acid
- topical retinoids: adapalene
- topical abx: clindamycin
moderate:
combination: topical retinoid + oral abx (lymecycline 3months at least/ erythromycin)
2nd line: anti-androgens COCP (dianette, Yasmin)
severe acne:
- oral retinoids (roaccutane, isotretanoin)
laser and dermavate for keloid scarring
side effects of roaccutane
- DEPRESSIVE
- DRY skin (lips)
- TERATOGENIC (two contraceptives needed and wait at least 6wks before conceiving)
- hypertrigleridaemia (LFTs before, durine and once after)
- can only prescribe one month at a time
- avoid alcohol
- hair thinning
- nose bleeds
eczema causes, aggravating factors
papules and vesicles on an erythematous base
atopic eczema usually develops by early childhood and resolves in teenagers
causes:
- FHx atopy: allergic rhinitis, eczema, asthma
- genetic - filaggrin gene mutations
aggravating factors:
- allergens pollens
- pets
- chemicals and food
- sweating, heat
- infection
types of eczema
discoid:
- well defined patches often infected with staph
pompholyx: itchy small vesicles
Id reaction: reaction to inflammation/ infection on skin - reaction occurs away from site
asteatotic eczema: dried up riverbed pattern
varicose eczema:
- varicose veins
- scaly itchy dry
- lipdermatosclerosis - red and painful leg. hx cellulitis
- champagne bottle legs - oedema proximal
varicose eczema risk factors
obesity
pregnant
DVT
immobility
complications of eczema
- bacterial infection
- viral infection - mollusc contagiosum: pearly papules with central umbilication
- viral warts and ECZEMA HERPETICUM –> IV ACYCLOVIR
management of eczema
- avoid triggers
- frequent emollients: dermabase
- bandages
- soap substitutes
topical:
- steroids for flare ups
- immunomodulators e.g. tacrolimus
oral:
- antihistamines
- abx: flucloxacillin for 2ndry bacterial infection
- acyclovir for 2ndry herpes infection
- phototherapy
- immunosuppressants: oral prednisone, azathioprine, ciclosporin
eczema clinical features
- itchy
- erythematous dry scale
- chronic scratching
- excoriations
- vesicular weepy
- infancy: face
children: elbow & knee flexures
adults: face, trunk, hands
