Demodex infestation in a child with leukaemia: treatment with ivermectin and permethrin.

Abstract

Demodex mites are almost ubiquitous on older adult skin but are infrequent in young children. In immunocompromised patients, demodicosis may be more frequent and severe, and systemic therapy may be needed to achieve clinical resolution. A six-year-old boy having maintenance chemotherapy for acute lymphoblastic leukemia presented with widespread erythema and scaling of the face. Skin scrapings were negative and the eruption worsened despite the completion of chemotherapy and the use of topical corticosteroids. Pustules developed on the face and around the eyelids, associated with bilateral blepharitis and lower lid chalazia. Skin biopsy then revealed heavy infestation with Demodex folliculorum. The child was treated with a combination of topical permethrin and oral ivermectin, with a total of four doses of ivermectin given over 6 weeks. The facial eruption had completely resolved 3 months after initiation of this combined treatment. Demodex infestation can cause dramatic facial and eyelid inflammation in immunocompromised patients. Oral ivermectin, in combination with topical permethrin, can be a safe and effective treatment for severe demodicosis.