Derm Flashcards
4 causes of burns
- thermal
- electrical
- Contact
- chemical
pathology and complications of burns
- haemolysis
- leakage of plasma into interstitial space
- extravasation and hypovolaemic shock
- protein loss
- secondary infection
- ARDS
- compartment syndrome
general burns mx
- IV morphine
- IX = ECG, CXR, fluid balance chart
- wound dressings
- limit hypothermia
- aggressive fluids and UO monitoring
- nutrition
Fluid resus calculation in burns
- Adults = initial 24hrs 4ml x weight x % TBSA
- children = 3ml x weight x % TBSA
- 50% of the fluid calculated given in first 8 hours, remaining in 16hrs
TBSA means
- total body surface area burned
- extent and depth
most accurate method to measure burns
lund and browder chart
Superficial burn
- epidermis deepest later involved
- dry, blanching, erythema
- painful
superficial partial thickness burn
- Upper epidermis
- blisters, wet, blanching, erythema
- painful
deep partial thickness burn
- lower dermis
- yellow or white, dry, non blanching
- decreased sensation
full thickness burn
- subcutaneous tissue
- leather, white, non blanching, dry
- painless
assessing rashes - distribution
- Acral = hands and feet
- Extensor = elbows, extensor surfaces
- Flexural = axilla
- Follicular = face, sebaceous glands
- Dermatomal
- Seborrhoeic = scalp
assessing rashes = configuration
- Discrete = separated lesions
- Confluent = merged
- Linear
- Discoid = same colour
- Target
- Annular = colour change
Assessing rashes - colour
- erythematous = red, blanches
- purpuric/ petechia = caused bysmall bleeds
- hyperpigmented = darker skin
- hypopigmented = lighter skin
- depigmented = white
assessing rashes - morphology
- macule = flat altered colour
- papule = solid raised lesion
- vesicle = clear fluid
- pustule = pus filled
- wheal - oedematous papule or plaque
A-E dermatology
- Asymmetry
- Border
- Colour
- Diameter
- Evolving
S+S acne
- Open (blackheads) and closed (whiteheads) comedones
- pustules
- nodules
- face, chest, back
- Mild = <30, mod = 30-125, severe >125
Mx acne
- hygeine etc
- topical benzoyl peroxide 1st line
- topical abx if infected = clindamycin
- oral abx
- isotrenitoin
cellulitis common organisms
- staph aureus
- strep pyogenes
Mx cellulitis
- flucloxacillin or erythromycin
- analgesia
exogenous eczema
- external factor or skin insult causes
- allergic contact dermatitis
- photosensitive
- post traumatic
- drugs
endogenous eczema
- atopic
- seborrheic
- discoid
- lichen simplex
brief patho of eczema
- breakdwon of skins natural barrier
- subsequent IgE mediated response
S+S eczema
- flexor surfaces
- pruritus
- dry skin
mx atopic eczema
- emollients
- topical corticosteroids
- topical calcineurin inhibitors (tacrolimus)
- bandages
- oral steroids
- antiseptics
SE topical steroids
- burning/stinging
- thinning
- striae
- acne
HSP background
- small vessel vasculitis
- caused by deposition of IgA complexes in small arteries –> complement activation
- hx recent UTRI
S+S HSP
- purpuric lesions on skin
- extensors
- symmetrical
- colicky abdo pain
- joint swelling
- glomerulonephritis
Ix HSP
- urinalysis = proteinuria, haematuria
- Normal platelets
- ESR raised
Mx HSP
- analgesia
- steroids = pred 1mg/kg
Impetigo most commonly caused by
- staph aureus
- highly infectious
S+S impetigo
- recent damage to skin
- pustules that pop and crust = yellow
- itchy
- clinical dx
Mx impetigo
- 5 days hydrogen peroxide 1%
- topical abx = mupirocin
- keep off school until lesions dried
Where is lichen planus most commonly found
- flexor surfaces and mucous membranes
- t cell mediated autoimmune disorder
S+S lichen planus
- genitals and inside vagina
- palms, soles and flexor arms
- acute px
- purpuric papular lesions
- white lace like in mouth
Mx lichen planus
- topical steroids like clobetasone butyrate
histology lichen planus
- saw tooth patterns of epidermal hyperplasia
- t cell infiltration of dermis
- reduced malanocytes
lichen sclerosis
- small well demarcated white plaques
- external genitals, not inside
- itchy
psoriasis appearance
- well demarcated white/red erythematous plaques
- silver scale
- extensor surfaces
- nails = pitting, ridging, oncholysis
psoriasis mx
- emollients and moisturisers
1. potent corticostteroid OD and Vit D analogue 4w
2. Vit D analogue BD
3. Corticosteroids BD and coal tar - Short acting dithranol
- retinoids
- phototherapy
- systemic = methotrexate, ciclosporin, biologica
psoriasis background
- T cell mediated abnormal immune response
- T cells release cytokines = keratinocyte proliferation
mx rosacea
- sun protection
- avoid oil based products
- topical metronidazole cream/ ivermectin
- oral abx = doxy
- no steroids
mx scabies
- permethrin 5% before bed, wash off in morning, 7 days
RF malignant melanoma
- age
- UV
- skin type
-FHx
background MM
- proliferation of atypical melanocytes with potential for dermal invasion and metastasis
S+S melanoma
- asymmetrical, irregular, large, evolving lesion
Mx melanoma
- excision with extended margins
- chemotherapy if spread
squamous cell carcinoma clinical features
- Speedy SCC - grow weeks -months
- enlarging scaly or crusty lumps
- may ulcerate
- tender and painful
- sun exposed sites
precursor to scc is
actinic keratosis
mx SCC
- surgical excision with extended margins, Mohs
- 5-fluorouracil 4 weeks
- imiquimoid 6 weeks
features BCC
- slowly growing plaque/nodule
- skin pigmented
- shiny/pearly
- rolled edges
- telangiectasia
- central ulceration
- spontaneous bleeding
- asymmetry
biopsy of BCC shows
- apoptotic cells
- peripheral palisading of nuclei
- clefts of tumour tissue
- basophilic aggregations of basaloid keratinocytes with large nuclei and scant cytoplasm
Mx bcc
- surgery
- mohs if ill defined
- radiotherapy
tinea is caused by
dermatophyte fungus
4 types of tinea?
- capitis = scalp
- pedis = feet = athletes foot
- cruris = groin
- corporis = any other skin site
S+S tinea
- itchy and inflamed
- acute onset
- ring like lesion with scaly edge
mx tinea
- topical terbinafine 1%
- econazole
eczema herpeticum is
complication of atopic with HSV infection
S+S herpeticum
- Malaise, fever
- itchy, painful lesions
- crusted papules
- gritty eyes
- LN
Mx herpeticum
- urgent derm referral
- aciclovir
erythroderma caused by
rapid epidermal cell turnover
S+S erythroderma
- red hot itchy skin
- hot
- desquamation - malaise
Meds that cause SJS/TEN
- allopurinol
- anti epileptics
- sulfonamides
- salicylates
- imidazole
S+S SJS/TEN
- flu like prodrome
- painful rash starts on trunk
- macular rash blisters and desquamates
differentiate SJS and TEN
- SJS = <10% body coverage
- TEN = >30%
venous ulcers morphology
- irregular borders
- yellow fibrinous base
venous ulcers surrounding skin
- yellow brown to brown
- pinpoint petechiae
- lipodermatosclerosis
venous uclers often found
medial malleolar region
arterial ulcers usually found
pressure sites, distal points
morphology arterial ulcers
- dry necrotic base
- wel demarcated = punched out
surrounding skin arterial
- shiny atrophic skin
other findings in arterial ulcers
- weak peripheral pulses
- prolonged cap refill time
Molluscum contagiosum
- Pink or pearly whyte papules
- Central umbilication (dimpling) 5mm in diameter
- Anywhere apart from hands and feet soles
- Self limiting
Seborrhoeic dermatitis adults
- Eczematous lesions on sebum rich areas
- Otitis externa and blepharitis may develop
- Scalp = ketoconazole shampoo
- topical = ketoconazole
Urticaria
- Pale pink raised skin
1. Non sedating AH = cetirizine (up to 6w)
2. Pred
drugs that induce TEN
- Phenytoin
- Penicillins
- Carbamazepine
- Allopurinol
- NSAIDs
- Sulfonamides
what might exacerbate psoriasis
- trauma
- alcohol
- BB
- Lithium
- NSAIDs
- ACEi
- Antimalarials
- Withdrawal systemic steroids
dermatitis herpetiformis
- coeliac disease
- itchy vesicular
- extensor surfaces
actinic keratoses mx
- sun protection
- fluorouracil cream
- topical diclofenac
- cryotherapy
- currettage
Mx venous ulcers
- Compression bandaging
- Oral pentoxifylline
Mild acne mx
- 12 w course topical combo therapy = trenitoin + clindamycin or BP + clindamycin
Mx mod-severe acne
- ## 12 w of topical combo or topical + abx oral
SCC features
- sun exposed sites
- rapidly expanding, painless, ulcerated nodules
- cauliflower appearance
- may bleed