Eczema/Dermatitis Flashcards
How is eczema broadly classified?
- Exogenous
- Endogenous
Give two examples of exogenous eczema
- Photosensitive dermatitis
- Contact dermatitis
- Allergic
- Irritant
Give three examples of endogenous eczema
- Atopic eczema
- Seborrhoeic eczema
- Venous eczema
- Asteatotic eczema: caused by dry skin
What is the commonest form of eczema?
Give two risk factors for this eczema
Atopic eczema: 10-20% children, 2-5% adults.
- 90% +ve FHx atopy
- Polygenetic + environmental influence
- Filaggrin deficiency: important for skin barrier
- Psychological stress
Describe the characteristic skin lesion of acute eczema
Papules and vesicles on an erythematous base
Describe three presenting features of atopic eczema
- Itchy red/dark skin lesions
- Poorly defined edges
- Bleeding
- Papules/vesicles on erythematous base (acute)
- Scaling/thickened (chronic)
- Weep/crust (infected)
- Commonly on face, scalp, and flexors
- Young children: extensors
- Psychological impact
- Sleep disturbance
- Social restrictions: school, job etc.
Outline the diagnostic criteria for atopic eczema
-
Itchy skin condition plus 3+ of the following
- History of pruritus in skin creases; cheeks in infants
- Atopy PMH; atopy FHx in children <4yr
- General dry skin in the preceding year
- Visible flexural eczema; cheeks and extensors in <4yr
- Onset in first 2yr of life
Outline the different severities of atopic eczema
- Clear: normal skin and no active eczema
- Mild: areas of dry skin, and infrequent itching
- Moderate: areas of dry skin, frequent itching, and redness
- Severe: widespread areas of dry skin, incessant itching, and redness
- Infected: weeping, crusted, or pustules; with fever or malaise.
What age group typically develop atopic Eczema?
<12yr
Tends to resolve by teenage years; may recur
What immunological response occurs in atopic eczema?
How does it compare to psoriasis?
- Both are type 4 hypersensitivity reactions
- Atopic eczema features a TH-2 response
- Extracellular organisms
- High IgE and eosinophils
- Psoriasis features a TH-1 response
- Intracellular organisms.
List three exacerbating factors of atopic eczema
- Infections
- Staph. aureus is the most important trigger
- Irritants: soaps; detergents
- Contact allergens
- Sweating
- Climate: worse in winter
- Dietary: predominently in children
- Severe stress
How does eczema present differently on non-caucasians?
- Caucasians: red lesions seen on flexors
- Non-caucasians: dark lesions seen on extensors
Which demographic is most at risk of seborrhoeic eczema?
Male
Teens-20s
How is seborrhoeic eczema diagnosed?
Diagnosed based on distribution
Which condition has increased risk of seborrhoeic eczema?
HIV
Give three specific clinical features of venous eczema?
- Atrophie blanche
- “Champagne bottle” shape
- Induration (lipodermatosclerosis)
Why are elderly patients more prone to specific types of eczema.
Dry skin - asteatotic eczema
Normally Tx with moisturisers
Outline the management of atopic eczema
- Education
- Avoiding irritants: cool temp; frequent baths; avoid soaps
- Antihistamines
- Non-sedating for severe itching or urticaria
- Sedating if disturbed sleep
What antibiotics are given in infected eczema?
- Flucloxacillin: commonly S. aureus or Strep
- Penicillin-allergic: Erythromycin or Clarithromycin
What is Eczema herpeticum?
Dermatology Emergency
- Widespread eruption of eczema with punched-out lesions
- due to Herpes simplex infection
- Serious complication of atopic eczema
- Systemically unwell with fever and malaise
