Abstract: Acquired reactive perforating collagenosis (ARPC) is the most common subtype of reactive perforating collagenosis (RPC). Its pathogenesis remains unclear, and no standardized treatment protocol has been established to date. Herein, we report a case of ARPC with poor response to conventional topical and systemic medications. After 4 weeks of dupilumab treatment, the pruritus was completely relieved and the lesions flattened; the skin lesions almost resolved after 4 months of therapy. No recurrence was observed during 1 year of follow-up after drug withdrawal. In addition, we summarized and analyzed 23 previously reported cases of RPC/ARPC treated with dupilumab. The results showed that pruritus was significantly improved within 1-4 weeks of treatment in most patients, with a mean lesion clearance time of 9.6 weeks, and no severe adverse reactions occurred during treatment. Cases in this paper and previous literature reports have demonstrated that dupilumab is safe and effective for the treatment of ARPC, providing a novel therapeutic option for patients with poor responses to conventional therapy.

Key words: dupilumab, acquired reactive perforating collagenosis