Chapter 2. Scabies
Scabies is another condition that, in infants, can be very difficult to distinguish from atopic dermatitis as both conditions are highly pruritic and can occur in similar widespread distribution. Scabies is a common infectious dermatosis produced by infestation with the Sarcoptes scabiei mite (PICTURE A). It results when an impregnated female mite burrows through the outer epidermis and deposits her eggs in the skin.
The rash of scabies is polymorphous and may appear papular, nodular, eczematous, or urticarial; often all lesions are seen together in the same patient (PICTURE B). In infantile scabies, small pustules are often seen on the lateral surfaces of the palms and soles; these are not typical for atopic dermatitis. Additionally, facial involvement is more typical of atopic dermatitis than scabies. If burrows are present, this is diagnostic of scabies. If necessary for confirmation, a parasite slide preparation may be performed in attempt to visualize the mite, eggs, or fecal material. Other family members should be queried regarding recent onset of itching or rash that can lead the examiner to the diagnosis of scabies.
The treatment of choice is 5% permethrin cream. Adults and children over the age of two are treated from the neck down; infants should have the head treated, as well. Success of treatment depends on all family members being treated simultaneously. Clothing and bedding should be washed in hot water.