A Case of Facial Sarcoptes scabiei in a Female Child.

Abstract

Dear Editor: Scabies in infants and young children differs from adult scabies infection and is frequently misdiagnosed1. An 8-year-old female presented with erythematous scaly pustules on her cheeks that start 3 months prior and had spread to her forehead. She was diagnosed at a local clinic with folliculitis, at which time she was treated with antibiotics and an antihistamine. The lesions were not resolved and she was brought to our hospital. Physical examination revealed scattered, 2~3 mm sized, erythematous scaly pustules over the face and an erythematous firm nodule on the left cheek (Fig. 1) with mild intermittent itching. She didn't have any skin lesions on the other site. This child had been hospitalized for 2 months due to burn injuries across the body before 6 months ago, but was found to be immunocompetent and there were no particular abnormal findings. There was no family history of similar lesions. Differential diagnoses of eosinophilic pustular folliculitis and contact dermatitis were considered. Histopathologic findings of a skin biopsy showed foreign materials considered to be scabies located in the upper portion of the epidermis with many eosinophils (Fig. 2A). To confirm the diagnosis, skin scraping of papule on her left cheek with mineral oil of the face was examined under light microscopy and scabies, eggs and scybala were found (Fig. 2B, C). We treated her with crotamiton cream, however could not follow-up her because she had return to homeland, Kazakhstan. Fig. 1 Scattered, 2~3 mm sized, erythematous scaly pustules and a firm nodule on the face. Fig. 2 (A) Foreign materials considered as scabies were located in the upper portion of the epidermis with lots of eosinophils (H&E, ×400). (B) Scabies, (C) eggs and scybala were found on the skin scraping of papule on her left cheek with mineral ... Scabies can be one of the most difficult conditions to diagnosis because of variable clinical features2. Scabies should be considered in infants or young children with generalized itch of recent onset. The classical eruption of scabies presents as pruritic papules, vesicles, pustules and linear burrows3. However, most young patients only have an admixture of primary lesions with excoriation, eczema, crusting and/or secondary infection. Excoriations, crusting and eczema can completely obscure these primary lesions, which is why scabies in infants and young children is frequently misdiagnosed4. Our patient represents an unusual case of Sarcoptes scabiei infection exclusively confined to the face. Among children's scabies infection, the frequency of infection on the face is only 8.9%5, and infection confined to only the face in immunocompetent children has not been reported until now, to the best of our knowledge. We propose some precipitating factors in this case. First, the patient had hypertrophic scars on the arms and hands due to previous burns. The hypertrophic scarring might provide a poor environment for living scabies. Second, the facial involvement of scabies is a known feature for infants, children and immunocompromised patients. The reason may be related to different cutaneous microbiomes, such as malassezia species. In cases of non-typical clinical symptoms of scabies infection in children, the elderly, and immunocompromised patients, who may suffer long periods without being treated properly as in this case, a spread of infection can occur. Dermatologists should bear in mind that scabies infection is not uncommon with recalcitrant persistent itch, and that signs such as pruritic papules and linear burrows may disappear.