Antiphosphatidylserine/prothrombin antibodies (aPS/PT) and risk of obstetric anti‐phospholipid syndrome

Abstract Objective Assessment of the prevalence of anti‐phosphatidylserine‐prothrombin antibodies (aPS/PT) with OAPS and SN‐OAPS in Chinese patients. Methods This retrospective study proceeded at Ren Ji Hospital, Shanghai, China, from January 2019 to January 2020. Two hundred eleven OAPS, 68 SN‐OAPS, 81 disease controls, and 30 healthy donors were enrolled. IgM and IgG aPS/PT, IgM/IgG ‐ aCL, and IgM/ IgG/ anti‐β2GPI antibodies were tested by ELISA while LAC was tested by clotting assays. All the patients were followed up and tested at least twice over 12 weeks apart. Results Thirty‐three OAPS (15.64%) and 31 SN‐OAPS (45.59%) were positive for aPS/PT. aPS/PT IgM showed a high Youden index (.813), which classified OAPS and SN‐OAPS patients from healthy controls and other autoimmune diseases. aPS/PT showed a stronger relationship with LAC. Of the 25 OAPS women positive for IgM aPS/PT, 19 (79%) LAC were positive, while of the eight women positive for IgG aPS/PT, 100% were found LAC positive. Conclusion aPS/PT antibody showed an efficient diagnostic value for Chinese patients with OAPS and SN‐OAPS, which could be a potential risk predictor for obstetric complications.