derm Flashcards
NICE criteria for dx atopic dermatitis
Itchy skin + 3/5 of
- visible flexural eczema (eryhtematous, itchy, poorly demarcated rash) face, or scalp - cheeks/ extensors if <18m
- Hx of felxural eczema
- Hx dry skin
- Hx atopy (in dividual/ 1st degree relative if <4yo)
- onset <2yo (dont use in <18m)
3 complicaitions of eczema
Eczema herpeticum - emergency, HSV inffection 2o to atopic dermatitis
superficial bacterial infection (stap/strep)
erythroderma (emergency) - widespread erythema >90% skin surface Leads to: heat and fluid loss –> hypothermia and systemic Sx
what type of hypersensitivity is atopic dermatits
Typ1 hypersensitivity - IgE mediated
give stepwise topic mx in eczema
- emmolient (Aveeno, E45, Diprobase)
- Steroids -
- mild: hydrocortisone, Mod: eumovate, Potent betnovate, V. potent: Dermovate
how do the following subtypes of psoriasis present
- plaque psoriasis
- flexural
-guttate
- pustular
plaque - most common, well-demarcated red, scaly patches on extensor surfaces, sacrum, scalp
flexural - smooth patches on skin
(affects skinfolds (armpits, under breasts, genital areas - smooth, shiny scaling)
guttate - strep infection triggered rash, multiple red, teardrop leasions
pustular - palms & soles
2 non-skin features of psoriasis
nails: pitting, onycholysis (separation of the nail from the nail bed)
subungual hyperkeratosis, loss of the nail
arthritis
molluscum contangiosum advice
self-limiting (12-18m)
but contagious, so dont share towels etc
school exclusion not required
what is the difference in presentation between lichen planus and lichen sclerosus
Lichen
planus: purple, pruritic, papular, polygonal rash on flexor surfaces. Wickham’s striae over surface. Oral involvement common
sclerosus: itchy white spots typically seen on the vulva of elderly women
Mx options for actinic keratosis ( give 3)
prevention of further risk: e.g. sun avoidance, sun cream
fluorouracil cream: typically a 2 to 3 week course. The skin will become red and inflamed - sometimes topical hydrocortisone is given following fluorouracil to help settle the inflammation
topical diclofenac: may be used for mild AKs. Moderate efficacy but much fewer side-effects
remeber actinic keratosis on sun exposed areas of the body
x2 differences in appearance between Plaque psoriasis and eczema
found in similar areas but
plaque posriasis:
- well defined borders
- silvery scale
Eczema
- poorly defined borders
- no silvery scale
give 2 main causes of impetigo
strep pyogenes & staph aureus** most common
1st line mx in impetigo if
- systemically well
- extensive disease (systemically unwell)
well: Hydrogen peroxide 1% cream (antiseptic) (Fusidic acid 2% - antibiotic, 2nd line)
unwell: oral fluclox (erythromycin 2nd line)
what bacteria is a golden crust associated with
staph aureus
should children be kept off school if they have impetigo?
yes - contagious
describe
- mild
-mod
-sev acne
mild - open & closed comedones, may have sparse inflammatory lesions
mod - widespread non-inflammatory lesions & neumerous papules & pustules
sev - extensive inflammatory lesions, with nodules/pitting/scarring
give the stepwise max for acne (5)
single topical therapy - topical retinoids/benzoyl peroxide)
topical combination therapy ( topical antibiotic, benzoyl peroxide, topical retinoid
- oral Abx (tetracyclines - lymecycline, doxycycline erythmomycin in pregnancy ) - max use 3 months
co-prescribe topical retinoid/benzoyl peroxide - COCP in women (diannette aka co-cyrindiol)
- oral isotretinoin ( specialist)
x eczema complication
bacterial infection of eczema
eczema herpeticum
bacterial - oral Abx (e.fg. fluclox)/ admit if severe
eczema herpeticum - oral aciclovir ( IV if severe)
stepwise mx in eczema
maintenance
flares
maintenance
- avoid irritation
- emollients (thin creams e.g. E45, Diprobase cream, aveeno cream, cetraben cream) (thick, greasy e.g. hydromol ointment, diprobase ointment, cetraben ointment)
flares
steroid
steroid ladder
Mild - hydrocortisone (0.5-2.5%)
Mod - Eumovate
Potent - Betnovate
V. potent Dermovate
features of a BCC (x4)
most common type - nodular
- sun-exposed sites (head and neck)
- initially a pearly, flesh-coloured papule
- telangiectasia
- may later ulcerate - leaving a dcentral ‘crater’
what cream can be used in actinic keratosis management which may cause redness and inflammation of skin
fluorouracil cream: 2 -3 week course.
topical hydrocortisone is given following fluorouracil to help settle the inflammation
define bowens disease
precancerous dermatosis - precursor to SCC (5-10% chance of becoming SCC)
describe the features of Bowens disease (x4)
red, scaly patches
10-15 mm
slow-growing
sun-exposed areas
Mx for bowens disease
topical 5-fluorouracil cream (BD, 4wks)
causes significant inflammation/erythema - so give Topical steroids (hydrocortisone) - like actinic keratoses Mx, but this is 2-3 wks
what are the 4 main types of melanoma
superficial spreading (70% - arms, legs, backs, chest , yougn people) - mole w/ diagnostic features
nodular 2nd commonest (sun exposed skin, middle aged - red/black bleeding/oozing lump)
lentigo maligna less common - chronically sun-exposed skin, older people - mole w/ diagnostic features
acral lentiginous - rare
(Nails, palms, soles - in darker skinned people) - subungual pigmentation (Hutchinsons sign) or on palms/feet
apart from webs of the hands, where else does scabies present
axillae,, extensor surfaces, upper back, lower trunk, genitals, peri-anal
presents - inear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist
in infants, the face and scalp may also be affected
secondary features are seen due to scratching: excoriation, infection
what pt group gets crusted scabies
hyperinfestation in immunocompromised
Presents: Extremely thick, hiyerkeratotic, scaly, fissured skin
- Inflammation with >1million mites (normally 10-20)
- High eosinophil count, IgE and IgG
- High risk of 2ᴼ infection and sepsis (partly due to underlying immune suppression)
1st & 2nd line Mx in scabies
permethrin 5% is first-line
malathion 0.5% is second-line
treat whole household at the same time
instructions for applying permethrin & malathion
creams for scabies
apply to skin
allow to dry and leave on the skin for 8-12 hers (permethrin), or for 24hrs (malathion)
wash off
reapply if insecticide is removed during the treatment period, e.g. If wash hands, change nappy, etc
repeat treatment 7 days later
( day 1 and day 8)
tx in norwegian scabies
norwegian = crusted
oral Ivermectin & isolation
what type of hyperwsensitivty reaction causes contact dermatitis
Type VI
Type IV hypersensitivity reactions are also known as delayed-type hypersensitivity as the reaction occurs 48-72 hours after exposure to an antigen. They are T-cell mediated and do not involve antibodies
what type of Gell and Coombs hypersensitivity raction causes anaphylaxis
Type I - IgE mediated
which of the sx of rosacea typically presents initilally
flushing is often first symptom
typically affects nose, cheeks and forehead
telangiectasia are common
later develops into persistent erythema with papules and pustules
rhinophyma
ocular involvement: blepharitis
sunlight may exacerbate symptoms
what ophtho condition is associated with rosacea
blepharitis
