Comment on: "Is There a Role for Therapeutic Drug Monitoring in Patients with Hidradenitis Suppurativa on Tumor Necrosis Factor‑α Inhibitors?"/Reply

Differentiating clinical features, such as involvement of other typical locations, along with complementary evaluation, including histopathological, endoscopic and imaging exams, enable the distinction between these conditions. Besides common clinical manifestations, chronic fistulizing perianal HS and IBD, especially CD, share pathophysiological features [5, 6]. The British Society of Gastroenterology consensus guidelines on the management of IBD stated that optimal therapeutic ranges for adalimumab and infliximab depend on the clinical context, suggesting that higher infliximab doses may be beneficial for perianal fistulizing disease, with target levels > 10 pg/mL associated with better response [7]. [...]evidence supports that we should target higher TNFa inhibitor concentrations in perianal fistulizing CD than in mucosal disease. Comment on: "Is There a Role for Therapeutic Drug Monitoring in Patients with Hidradenitis Suppurativa on Tumor Necrosis Factor-a Inhibitors?" Accepted: 19 April 2022 / Published online: 4 June 2022 © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2022 Tumor necrosis factor (TNF)-a inhibitors, including adalimumab-the fully human immunoglobulin G1 (IgG1) monoclonal antibody and the only biologic indicated for hidradenitis suppurativa (HS)-and infliximab, a chimeric mouse-human IgG1 monoclonal antibody, have revolutionized HS management.