Case Report: Upadacitinib for Acrodermatitis continua of Hallopeau: a case series with literature review

Background Acrodermatitis continua of Hallopeau (ACH) is a relatively rare chronic skin disorder often associated with immune system abnormalities. Conventional systemic therapies and biologics have limited efficacy and are prone to relapse, highlighting the urgent need for new treatment options. Upadacitinib, a highly selective JAK1 inhibitor, has shown promising results in various inflammatory skin diseases; however, its application in ACH has rarely been reported. Methods A retrospective analysis was conducted on 6 ACH patients treated with upadacitinib at our outpatient clinic from 2023 to 2025. Clinical data, including demographics, disease duration, sites involved, prior treatments, dosage, treatment duration, DLQI scores, and adverse events, were collected. Meanwhile, a narrative literature search was performed in PubMed, Web of Science, and Embase to identify studies on JAK inhibitors in ACH. Results Among 6 patients (2 males, 4 females; mean age 42.8 years, range 22–59; mean disease duration 1.9 years, range 6 months–4 years), all received upadacitinib 15 mg/day for 3–13 months. Most improved in skin and nail lesions; mean DLQI decreased from 14.0 to 6.0. Response was assessed primarily by clinical signs: complete response required resolution of pustules and erythema with nail improvement; partial response required ≥50% clinical improvement. One patient had clinical complete response (DLQI 71%) and another clinical partial response (DLQI 42%). No adverse events occurred. Notably, 3 patients who failed tofacitinib improved after switching, though this is preliminary and may be confounded by cumulative exposure. Conclusion In this small retrospective case series, upadacitinib 15 mg/day appeared effective in ACH, with most patients showing clinical improvement, although two had subthreshold DLQI improvement despite clinical response. The literature review indicates that JAK inhibitors, particularly upadacitinib, show promising efficacy in ACH, but current evidence remains limited to case reports and small series. Response after switching from tofacitinib in three patients is preliminary and may be confounded by cumulative exposure; larger prospective studies are needed to confirm efficacy, safety, and the value of switching.