Abstract: This paper reports a case of dupilumab treatment for childhood atopic dermatitis predominantly manifested as twenty-nail dystrophy. The patient was an 8-year-old girl who presented with thickening, opacification, deformity and rough nail plates of all twenty fingernails and toenails. The nail lesions had progressively worsened over 2 years without subjective symptoms, and previous oral antifungal therapy yielded no satisfactory response. Medical history review revealed generalized xerosis and pruritus prior to the onset of nail lesions. Combined with clinical manifestations and laboratory examinations, the patient was diagnosed with atopic dermatitis complicated by twenty-nail dystrophy. The patient received subcutaneous injection of dupilumab at an initial dose of 600 mg, followed by dose tapering as scheduled. During the treatment period, the patient's generalized cutaneous xerosis and pruritus were effectively alleviated, and the fingernails and toenails recovered well, and no recurrence was observed during the 6-month follow-up after drug discontinuation.

Key words: twenty-nail dystrophy, dupilumab, atopic dermatitis