Primary Care - Dermatological Flashcards
What causes atopic eczema?
Overactivity of Th2 cells»_space; increase IL4/5»_space; increased IgE production due to a specific allergen
What is the distribution of eczema?
Flexor surfaces
What is the diagnostic criteria for atopic eczema?
Itchy skin condition plus 3 of the following:
- History of itchiness in skin creases
- History of atopic disease
- General dry skin
- Visible flexural eczema
- Onset in first 2 years of life
What causes eczema herpeticum?
Herpes simplex virus type 1 infection superimposed onto active atopic eczema
How does eczema herpeticum present?
Widespread vesicular, pustular rash that eventually crusts over
Fever
Lymphadenopathy
What is the treatment for severe eczema herpeticum?
IV acyclovir
in mild, treatment unnecessary
What are the first line treatments for eczema?
Emollients (500g per week in adults) - creams, lotions, ointments, soap substitutes
Topical steroids - hydrocortisone (mildest) to dermovate (most potent)
How much does one fingertip unit cover?
2 palms of area
What are some complications of eczema?
Lichenification in adults
Staphylococcal infection = scalded skin syndrome
Eczema herpeticum
How do you treat an infective exacerbation of eczema?
Flucloxacillin for 14 days (erythromycin if penicillin allergy)
What genetic mutation is associated with eczema?
Filaggrin
Where and how does discoid eczema present?
Symmetrical oval erythematous patches/plaques on extremities
Extremely itchy especially at night
What age is discoid eczema more common in?
Over 60 years old
How does psoriasis present?
Extensor surfaces
Itchy circular symmetrical erythematous plaques with fissuring
Nail bed is affected in 50%
How does guttate psoriasis?
Acute symmetrical raindrop circular plaque lesions on trunk/limbs
What is Auspitz’ sign?
Bleeding on scraping of a psoriatic lesion
What is Kobner’s reaction?
Lesions arising from trauma in psoriasis
What nail changes are seen in psoriasis?
Pitting
Onycholysis
Subungual hyperkeratosis
Oil drop discolouration
What causes a relapse of psoriasis?
Stress
Smoking and alcohol
NSAIDs
Lithium
How else might psoriasis manifest itself?
Psoriatic arthritis = polyarthritis, rheumatoid-like
What antigens is psoriatic arthritis associated with?
HLA-B27 (also ankylosing spondylitis)
HLA-DR4 (also RA and type 1 diabetes)
What topical treatments are used for psoriasis?
Emollients e.g. diprobase, dermol
Topical vitamin D
Topical steroids
What non-topical therapies can be used for psoriasis?
Methotrexate
Biologics e.g. infliximab
Phototherapy (UVB/PUVA)
