Eczema Flashcards
What does eczema mean?
Inflammation of the skin, it means the same as dermatitis
How can the causes of eczema be divided?
Exogenous causes e.g. Photosensitive, Contact Dermatitis (Allergic or Irritant Dermatitis)
Endogenous causes- Atopic, Seborrhoeic, Venous, Asteatotic, Discoid
What are the three atopic diseases?
Atopic eczema
Asthma
Hayfever
What are the symptoms of eczema?
Itch- can be very unpleasant Weeping skin Crusting when fluid dries out Scaling/thickening of the skin Sleep disturbance due to itch Colour change- especially in pigmented skin due to itch Bleeding (may become darker or lighter)
Describe some of the differences between eczema and psoriasis
Eczema has a tendency to affect the flexor surfaces rather than the extensor surfaces seen in psoriasis ( but this is mostly in white people, less so in ethnic minorities)
Eczema lesions are not well demarcated with clear boundaries like the plaques seen in psoriasis
Eczema is less scaly whereas psoriasis is associated with silvery scales
Eczema is very very itchy and so has associated excoriations
What are some complications of eczema? What would indicate this?
Infection- often with Staph Aureus (>90%) or Group A Strep.
Weeping, crusting or pustules
What could be a sign of secondary infection in eczema?
Weeping, crusting or pustules
What is a concerning infection in children with eczema that can cause multiple punched out lesions?
Herpes Simplex Virus leading to Eczema Herpeticum
HSV infects the skin of patients who are susceptible, such as with atopic eczema due to the breaks in the skin surface.
What does eczema herpeticum look like?
Eczema herpeticum is caused by HSV-1
Groups of small blisters initially and then more can form
Blisters contain a clear fluid that then develops into pus
They may weep or blead
Heal which rarely can result in scaring
Multiple punched out lesions
How is eczema herpeticum diagnosed?
Clinical diagnosis
Swab the blisters and send for PCR, MC+S if could be bacterial too
What is the treatment for eczema herpeticum?
Acyclovir- anti-viral therapy
What are the features of seborrhoeic eczema?
Red scaly rash that is itchy and affects the scalp, eyebrows, naso-labial folds, cheeks and flexures
What should be tested for in patients with severe seborrhoeic eczema?
HIV- Severe forms of seborrhoeic eczema are associated with being HIV positive
What is the cause of seborrhoeic eczema?
Overgrowth of skin yeasts- e.g. Malassezia
What is the treatment for seborrhoeic eczema?
Mild topical steroids or anti-fungal preparations
What are the two types of contact dermatitis?
Allergic
Irritant
What type of hypersensitivity is an allergic contact dermatitis?
Type IV
What are some causes of allergic contact dermatitis?
Nickel- jewellery, watches, coins, keys,
Rubber- marigold gloves
Latex
Lanolin- creams, cosmetics
Chromate- leather, cement (builders hand eczema)
Hair-dye allergy (due to PPD)
Dermatitis is seen where the object is in contact with the skin, there is often a sharp cut-off where the contact ends
For allergic contact dermatitis do patients develop it the first time they come into contact with the allergen?
No sensitisation must occur first
This is an example of a type IV hypersensitivity reaction