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386 Chapter 9: Dermatology and soft tissues

Clinical features also important to use only low-potency steroids on
Patients have generalised dry skin (xerosis) along with thin areas of skin such as the face.
typical eczematous lesions. These are erythematous and Antibiotics are used for secondary bacterial infection.
scaly, and intense itching results in superficial abrasions In young children these may be parenteral; aciclovir is
(excoriation). Chronic inflammation of the skin causes used to treat eczema herpeticum.
thickeningtermedlichenification.Lesionsmayweepand Wetwraps consist of the application of topical agents
have tender tiny blisters termed vesicles especially when under bandages to facilitate absorption. Emollients
superinfection occurs. The distribution is age depen- may be administered in this way or coal tar may be
dent: used as a keratolytic in lichenified skin. If steroids are
Babies develop eczema predominantly on the face and appliedunderwetwrapsthedose/potencymustbede-

head; this may resolve or progress by 18 months to the creased as increased absorption may result in systemic
childhood/adult pattern. side effects.
Children and older patients tend to have lesions in the Antihistamines have not been shown to be effective in

flexures, such as the antecubital and popliteal fossae, reducing itching. Sedating antihistamines are used at
neck, wrists and ankles. night to improve sleep, reduce nocturnal scratching
and hence break the ‘itch-scratch-itch’ cycle.
Complications Topical tacrolimus, an immunosuppressant, is being
Staphylococcus aureus is found on the skin of 90%, which increasingly used in children prior to the use of high-
may result in acute infection (impetigenised eczema). potencysteroids.Itappearssafeandeffective;however,
Primary infection with herpes simplex may give a very the long-term risks are unknown, as it is a relatively
severe reaction known as eczema herpeticum, which in new preparation. Pimecrolimus is under study as a
the young may cause dehydration and is life-threatening. similar agent without systemic immunological effects.
PUVA or combination UVA and UVB are used in very

Investigations resistant eczema; however, therapy is expensive and
Patients show high levels of serum IgE; suspected aller- increases the risks of skin cancer.
gictriggers may be identified using skin prick or RAST
testing. Prognosis
Eczemahasafluctuatingcoursewithapproximately50%
Management resolving by 18 months, and few have problems beyond
There is no curative treatment. childhood.
Avoidance of exacerbating factors is essential. In ba-

bies it may be appropriate to either test for cow’s milk
allergy or to perform a therapeutic trial with a cow’s Contact dermatitis
milk protein free formula.
Definition
Generalised dry skin (xerosis) requires regular fre-

Contact dermatitis is an allergic or irritant-induced der-
quent use of emollient moisturisers especially af-
matitis arising from direct skin exposure to a substance.
ter bathing/showering. Cream preparations are water
based with emulsifiers and preservatives and they tend
Age
todrytheskin.Greasierpreparationssuchaswhitesoft
Most common in children and adult women.
paraffin achieve better moisturisation. A balance has
to be struck between application of sufficient grease
and cosmetic satisfaction. Greasier preparations are Sex
usually better tolerated prior to going to bed. F > M
Topical steroids remain the mainstay of treatment. If

used appropriately they are both safe and effective. Geography
The lowest potency that is effective should be used Exposure is most common in the home or industrially
and higher potency reserved for resistant cases. It is related.