Dermatology Flashcards
What is atopic dermatitis?
aka eczema. Chronic, autoimmune, pruritic inflammatory skin condition.
What is the atopic triad and how are they linked?
- Atopic dermatitis
- Allergic rhinitis
- Asthma
Associated cdtns have an increased IgE and if someone has atopic dermatitis they’re more likely to develop either allergic rhinitis or asthma or both.
RF for atopic dermatitis
- Family history
- Allergies
- Environmental triggers - changes in temperature, certain dietary products, washing powders, cleaning products and emotional events or stresses
What inherited abnormality causes eczema?
Loss of filaggrin gene
Note: Filaggrins are filament-associated proteins which bind to keratin fibres in the epidermal cells and therefore a loss of this can cause disordered barrier function.
Sx of atopic dermatitis
Acute:
red (erythematous)
weeping/crusted (exudative)
blisters (vesicles or bullae)
Chronic:
skin becomes less red but thickened (lichenified) and scaly
cracking of the skin (fissures)
Tx for atopic dermatitis
Emollients (thin or thick)
Topical steroids
Wet wraps
What is measles and is it a notifiable disease?
aka rubeola. A highly contagious viral infection.
Measles is a notifiable disease.
How is measles spread?
Airborne respiratory droplets
Who is at risk of measles?
- Infants who lost passive immunity from mother
- Unvaccinated traveller
- Immunodeficient travellers
- Pregnant women
Sx of measles
Prodrome (initial flu-like Sx):
Fever (40c)
Malaise
Loss of appetite
Conjunctivitis (red eyes)
Cough
Coryza (blocked or runny nose)
Exanthem (rash) - flat red spots appear 4th or 5th day after Sx start. Non-itchy rash begins on the face and behind the ears. Within 24hrs it spreads over the entire trunk and extremities.
Ix of measles
PCR - viral nasopharyngeal or throat swab
Blood and urine samples
Tx of measles
Mild: self limiting, supportive
If immunocompromised: ribavirin (antiviral)
How can measles and mumps be prevented?
Combined measles, mumps and rubella (MMR) vaccination with live attenuated vaccine.
Two dose vaccine strategy.
What is mumps and how is it spread?
A viral infection spread by respiratory droplets.
Notifiable disease
Sx of mumps
Prodrome (initial flu-like Sx):
Fever
Muscle aches
Lethargy
Reduced appetite
Headache
Dry mouth
Specific mumps Sx: Parotid gland swelling, either unilateral or bilateral
Ix of mumps
PCR testing - saliva swab
Tx of mumps
Self limiting, supportive tx
Describe pathophysiology of acne vulgaris
- Chronic inflammation in pockets within skin = pilosebaceous unit.
- Pilosebaceous units = tiny dimples containing hair follicles and sebaceous glands (produces sebum)
- Inc. sebum = trapped keratin (dead skin cells) = blockage pilosebaceous units = inc. swelling and inflammation (aka comedones)
- Androgenic hormones inc. sebum production = inc. sebum during puberty
What is the name of the bacteria that plays a role in acne vulgaris?
Propionibacterium acnes bacteria
Describe the appearance of lesions and scars in acne vulgaris
Macules - flat marks on skin
Papules - small, tender red pumps
Pustules - small lumps containing yellow pus
Comedones - skin coloured papules
Blackheads - open comedones w/ black pigmentation
Nodules - large painful red lumps
Ice pick scars - small indentations in skin that remain after acne lesions heal
Hypertrophic scars - small lumps in skin that remain after acne lesions heal
Rolling scars - irregular wave-like irregularities in skin that remain after acne lesions heal
Term to describe oily skin
Seborrhoea
Term to describe increased hair growth
Hirsutism
Tx of acne vulgaris
Topical benzoyl peroxide - reduce infl. + unblock skin
Topical retinoids - slow sebum production
Topical antibiotics - clindamycin
Oral abx - i.e. lymecycline
OCP - i.e. Co-cyprindiol (Dianette) stabilise hormone + dec. sebum production
Last line (if very severe) - oral retinoids i.e. isotretinoin
Why is it imp. to monitor oral retinoid intake?
Retinoids are highly teratogenic.
Needs careful follow-up and monitoring and reliable contraception in females.