Cutaneous fusariosis caused by Fusarium lichenicola in a child with hyper‐immunoglobulin E syndrome

Fusariosis is the second most common mold infection after aspergillosis, and keratomycosis is the most encountered implantation infection. Here, we report a case of a 4-year-old Han Chinese girl presenting with an itchy mass on her right face of almost 2 years' duration. Direct smear of the lesion sample was positive for fungal hyphae. Biopsy of the lesion showed many fungal hyphae in the epidermis and dermis. The pathogen was identified as Fusarium lichenicola by molecular sequencing and phylogenetic analysis based on the TEF-1alpha gene. Whole-exome sequencing analysis using her peripheral blood revealed a heterozygous mutation in the STAT3 gene, which is related to autosomal dominant hyper-immunoglobulin E syndrome (AD-HIES). The lesion improved following treatment with i.v. and intralesional amphotericin B, oral voriconazole and topical luliconazole cream. To our knowledge, this is the second reported case of a special localized cutaneous lesion caused by Fusarium species in a child with AD-HIES. Both cases suggest that STAT3 deficiency may increase susceptibility to fusariosis.