Abstract: 【Abstract】 To report the first case of cutaneous chronic active Epstein-Barr virus disease manifesting as persistent erythema multiforme in China. The 12-year-old female patient presented with recurrent erythema and blisters all over the body, accompanied by oral erosions for more than 5 months. Skin examination showed dark erythema scattered on the right upper eyelid and cheeks, as well as erosions and blisters arising in the dark erythema on the lower jaw; broad bean- to pigeon egg-sized blisters with clear fluids arising in erythema were scattered on the back, buttocks, and limbs, and some manifested as atypical targetoid lesions; there was a mung bean-sized erosion on the mucosa of the lower lip and the right buccal region each; the patient also presented with moon face and multiple striae atrophicae on the lower limbs. Histopathological examination of the skin lesions on the lower limb revealed basket-weave hyperkeratosis, epidermal necrosis, liquefaction degeneration of basal cells with subepidermal blister formation, and perivascular lymphocytic infiltration in the superficial dermis; direct immunofluorescence assay showed negative staining for IgG, IgM, IgA, and complement C3 among epidermal cells and at the basement membrane zone; enzyme-linked immunosorbent assay showed negative staining for serum antibodies against desmoglein 1/3 (Dsg1/3), BP180, and type Ⅶ collagen; immunohistochemical examination demonstrated partial positive staining for CD3, CD4, CD5, CD8, CD56, granzyme B, and Epstein-Barr virus-encoded RNA, positive staining for Ki67（> 70%）, but negative staining for CD20. The Epstein-Barr virus DNA level was measured to be 1.97 × 106 IU/ml in whole blood samples and 2.65 × 107 IU/ml in blister fluid samples. No mutation sites with functional significance were identified by whole-exome sequencing. Based on these findings, a diagnosis of cutaneous chronic active Epstein-Barr virus disease manifesting as persistent erythema multiforme was made. The patient was treated with methylprednisolone at a dose of 40 mg/d, intravenous drips of ganciclovir at 200 mg twice daily, etc., and discharged after improvement.

Key words: Herpesvirus 4, human, Epstein-Barr virus infections, Erythema multiforme, Child, Persistent infection, Lymphoproliferative disorders