Eczema & Psoriasis Flashcards
What is eczema?
a chronic inflammatory skin condition that is NOT autoimmune
it typically affects the FLEXURES
a.k.a dermatitis
Who typically presents with eczema symptoms?
it most frequently presents in childhood with 70-90% cases onset being before 5 years of age
What are the typical symptoms associated with eczema?
- dry skin
- itching
- erythematous lesions
- present on the flexures
it is an episodic disease of flares (exacerbations occurring as many as 2-3x a month) and remissions
in severe cases, disease activity can be continuous
What can happen to the skin in chronic eczema?
lichenification
- this involves thickening of the skin with hyperpigmentation + exaggerated skin lines
What are the RFs for eczema?
- past medical history or FHx of atopy (food allergies, hay fever, asthma)
- Filaggrin gene mutation
- environmental triggers - pets, pollen, house dust-mites
What are the potential complications associated with eczema?
infection:
* infection with Staphylococcus aureus, herpes simplex or a superficial fungal infection can occur
- herpes simplex infection can result in widespread eczema herpeticum
psychosocial issues:
* e.g. missing school, reduced self confidence, disturbed sleep, depression
How is eczema diagnosed?
What should be assessed at each consultation?
it is a clinical diagnosis
- at each consultation, the severity of the eczema + the psychosocial impact should be assessed
investigations may be performed to exclude differential diagnoses
What is the first line treatment for eczema?
emollients
these are first-line treatments for acute flares and remissions
these are moisturising treatments that will soothe and hydrate the skin
What is the treatment for eczema when skin is red and inflamed?
topical corticosteroids
- the lowest potency and amount of topical corticosteroid necessary for symptom control is prescribed
What is meant by the “finger tip rule”?
1 finger tip unit (FTU) = 0.5g
this is sufficient to treat a skin area twice the size of the flat of an adult hand
If there is persistent, severe itch despite topical corticosteroids, what treatment might be given?
a 1 month trial of a non-sedating antihistamine
if itching is affecting sleep - a short course of a sedating antihistamine is considered
If eczema is crusted, weeping, there are pustules or fever, what might be considered?
there is a chance of a secondary bacterial infection
antibiotic treatment should be prescribed
What is the definition of psoriasis?
a common, chronic autoimmune skin disorder characterised by hyperproliferation of keratinocytes
it tends to affect EXTENSOR surfaces
How does psoriasis tend to present?
- red/purple scaly patches on the skin
- dry / flaky skin
- itching / pain
- present on the extensors / scalp
patients with psoriasis are at increased risk of arthritis and CVD
What is involved in the pathophysiology of psoriasis?
it is multifactorial and not fully understood
- involves genetic and environmental factors
- it is often worsened by stress / trauma and improved by sunlight
What is plaque psoriasis?
- the most common sub-type that results in well-demarcated red, scaly patches
- affects the extensor surfaces, sacrum + scalp
What is flexural psoriasis?
psoriasis affecting the flexural surfaces
the skin is smooth
What is guttate psoriasis?
- transient psoriatic rash that is often triggered by streptococcal infection
- multiple red, teardrop lesions appear on the body
What is pustular psoriasis?
plaques / pustules that appear on the hands and soles of the feet
As well as the skin lesions, what other features are associated with psoriasis?
- symmetrical polyarthritis
- nail signs - onycholysis and pitting
What are the complications associated with psoriasis?
- psoriatic arthropathy in 10%
- increased incidence of metabolic syndrome
- increased incidence of CVD
- increased incidence of VTE
- psychological distress
What is the first-line treatment for chronic plaque psoriasis?
- a potent corticosteroid applied once daily
- vitamin D analogue applied once daily
- one is applied in the morning and the other in the evening
- trialled for 4 weeks as initial treatment
- regular emollients can be used alongside to reduce itching / scale loss
What is the second-line management for psoriasis?
if there is no improvement after 8 weeks:
- a vitamin D analogue is applied twice daily
What is the third-line management for psoriasis?
if there is no improvement after 8-12 weeks:
- a potent corticosteroid can be applied twice daily for up to 4 weeks
- OR a coal tar preparation applied once or twice daily
What are the recommendations for the use of potent corticosteroids?
- potent corticosteroids should be used for no longer than 8 weeks at a time
- very potent corticosteroids should be used for no longer than 4 weeks
- there should always be a 4 WEEK BREAK before starting another course of topical corticosteroids
What are the side effects of using topical corticosteroids?
Which places are more prone to these?
side effects:
* skin atrophy
* striae
* rebound symptoms
sensitive areas:
* the scalp, face and flexures are more prone to steroid atrophy
- topical steroids should not be used for more than 1-2weeks in a month
What are examples of vitamin D analogues?
How do they work?
they decrease cell division + differentiation, resulting in reduced epidermal proliferation
includes calcipotriol (Dovonex), calcitriol and tacalcitol
What are the benefits of using vitamin D analogues?
- unlike corticosteroids, they can be used in the long-term
- adverse effects are uncommon
- they do not smell or stain
they reduce the scale / thickness of the plaques, but not the erythema
cannot be used in pregnancy
What is a mild topical corticosteroid?
hydrocortisone (0.5-2.5%)
What are moderate topical corticosteroids?
- betamethasone valerate 0.025% (Betnovate)
- clobetasone butyrate 0.05% (Eumovate)
What are examples of potent topical corticosteroids?
- fluticasone propionate 0.05% (Cutivate)
- betamethasone valerate 0.1% (Betnovate)
What is an example of a very potent topical corticosteroid?
clobetasol propionate 0.05% (Dermovate)
