Topic I/6) Atopic dermatitis (eczema)

Question 1

atopy

Answer 1

an old clinical term used to describe a group of disorders, including asthma and hayfever; which occur in families, have characteristic wealing skin reactions to common allergens in the environment and where circulating antibodies are present in the serum (that could be transferred to the skin of non-sensitized individuals). T

Question 2

atopy best descibes who?

Answer 2

individuals who readily develop antibodies of the IgE class against common antigens in the environment

Question 3

etiology of atopic dermatitis

Answer 3

selective activation of TH2- type CD4 lymphocytes in the skin which drives the inflammatory process
raised serum total IgE-level
genetically complex, familial disease with a strong maternal influence
abnormalities in genes encoding the β-subunit of the high-affinity IgE-receptor, TH2 cytokine-genes, the α-subunit of IL-4 and RANTES.

Question 4

clinical features of atopic dermatitis

Answer 4

Itchy erythematous scaly patches –in front of elbows, ankles and behind the
knees and around the neck.
● Very acute lesions may weep or exudate and may show small vesicles.
● Scratching can produce excoriations, and repeated rubbing produces lichenification
● Post-inflammatory hyper- or hypo- pigmentation may occur (slowly fades)
● Follicular hyperkeratosis may occur – skin feels rough

Question 5

complication of topic dermatitis:

Answer 5

Secondary infections may occur (S.aureus)
● Cutaneous viral infections
● Eczema herepticum (Kaposi’s varicelliform eruption)
– appears as multiple small blisters and punched-out crusted lesions w/ malaise and fever

Question 6

treatment of atopic dermatitis

Answer 6

1.steroids (hydrocortisone,aclometasone,betamethasone)
2.topical immunomodulators(tacrolimus,pimecrolimus)
3.antibiotics(for bacterial superinfection,flucloxacillin
4.sedating antihistamines(hydroxizine)
5.bandaging
sesond line agents:Ultraviolet phototherapy ,Prednisolone ,Cyclosporin – inhibits IL-2 production by T-lymphocytes,Azathioprine