Mary Claiborne, MD; Shilpa Dass, MD; Robert M Lapus, MD; Samuel J. Prater, MD
Department of Emergency Medicine, McGovern Medical School at UTHealth, Houston, Texas
Children’s Memorial Hermann Hospital
11 year old African American female with trisomy 21, corrected congenital heart defect, and atopic dermatitis presented with generalized pruritus and scalinesss for 2-3 days. Mom has been putting petroleum jelly on the lesions, however because of the worsening appearance, she presented to the emergency department.
General- Non-toxic appearing female with typical Down’s physical characteristics
Skin- thick crusting and marked hyperkeratosis covering her forehead, auricular area, neck, chest, back, acral surfaces, wrists, interdigital webs and subungual areas of the fingers and toes.
Down’s syndrome (DS) is associated with various skin disorders. The differential for this child included seborrheic dermatitis, psoriasis, crusted (Norwegian) scabies, and ichthyosis. Scrapings examined under microscopy showed an abundance of live mites, confirming the diagnosis of crusted scabies. For unclear reasons, children with DS are predisposed to the development of crusted scabies. It may be related to immunologic dysfunction and poor cutaneous sensation, leading to decreased likelihood of the mite being mechanically removed and therefore increased infestation. Patients have generalized erosions, scaling, and hyperkeratotic crusted plaques affecting any skin surface. Nails can be dystrophic and have subungual hyperkeratosis. Surprisingly, itching may be absent or minimal.
Treatment for crusted scabies requires a prolonged course of permethrin and oral ivermectin. Some add keratolytics. Because crusted scabies creates breaks in the skin and primarily affects patients with weakened immune systems, patients are at higher risk for secondary bacterial infections.