The sensitivity of the new criteria was lower in our cohort (73% and 62% (without livedo racemosa)) than in the 2023 ACR/EULAR APS classification criteria validation cohorts (83% and 84%, respectively), mainly due to seronegative APS patients (n = 4), non-persistent positivity of the LAC test (n = 5) and patients with obstetric involvement who did not meet the newly defined clinical criteria score. This evidence concerns the gene LCT and autoimmune polyendocrinopathy.