Acquired Reactive Perforating Collagenosis Treated with Upadacitinib: A Case Report and Literature Review

Bo Xie,* Xiaoyan Zhang,* Xinxin Lei,* Yuting Zhang, Qin Zhang, Yujian Ye Department of Dermatology, Hangzhou Third People’s Hospital, Hangzhou Third Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, 310009, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yujian Ye, Department of Dermatology, Hangzhou Third People’s Hospital, Hangzhou Third Hospital Affiliated to Zhejiang Chinese Medical University, Westlake Road 38, Hangzhou, 310009, People’s Republic of China, Email yeyujian@hotmail.comAbstract: Acquired reactive perforating collagenosis (ARPC) is a rare perforating dermatosis linked to systemic diseases, with unclear pathogenesis and no standardized therapy. We report a 53-year-old male with ARPC who failed conventional treatments but improved rapidly with upadacitinib 15 mg/day for one month, followed by 15 mg every other day. After three months, most lesions resolved, leaving hyperpigmentation and scars. Literature review shows conflicting reports: one case of ARPC improved with upadacitinib, another developed ARPC during upadacitinib treatment for atopic dermatitis. Our findings suggest upadacitinib may be effective for ARPC, especially in pruritic patients, regardless of diabetes status.Keywords: Janus kinase inhibitor, reactive perforating collagenosis, upadacitinib