Non-criteria antiphospholipid antibodies anti-PT/PS, anti-Anexin V: benefit in diagnostics of antiphospholipid syndrome?

Objective Background: Antiphospholipid syndrome (APS) is a hypercoagulable state accompanied by the occurrence of antiphospholipid antibodies (APA), which non-specifically affect the process of hemostasis. Clinically, APS is manifested by arterial or venous thrombosis and reproductive loss. The classification of APS is very precisely defined, and therefore at least one clinical and at least one laboratory criteria must be met for a definitive diagnosis of APS. Laboratory criteria include positivity of at least one anti-cardiolipin, anti-β2-glycoprotein-I and lupus anticoagulant antibodies. Aims: Determination of the frequency of anti-phosphatidylserine/prothrombin (aPS/PT) and anti-Annexin V antibodies as new laboratory markers of APS in patients with suspected suspicion of APS. Material and Methods Methods: Determination of aPS/PT, anti-Annexin V was performed by ELISA using QUANTA Lite aPS/PT IgM and QUANTA Lite aPS/PT IgG and anti-Annexin V IgG/IgM kits. Results Results: In a total of 395 patients, APA positivity was found in 67 (17%) patients. In terms of the severity of the clinical manifestation of APS, it is important to assess the severity of the combination of single antibody combinations, where single positivity was found in 47 (11.9%) patients, double positivity in 17 (4.3%), triple positivity in 3 (0.8%). There were 328 (83%) seronegative patients (SN-APS), of which 161 (49.5%) were patients who met the clinical criteria for APS. In the group of SN-APS patients with clinical manifestations of APS, non-criteria positivity of anti-Annexin V antibodies was found in 7 (4.3%), aPS/PT positivity in 17 (10.5%), clinically significant aPS/PT level was found in 5 (3.1%) patients. Conclusion Conclusions: In our cohort, we detected 17% (67) of patients according to current APS laboratory criteria. Using the detection of anti PS/PT and anti-annexin V, the proportion increased by another 24 patients in the group of seronegative patients with fulfilled clinical criteria of APS. For this reason, we consider it beneficial to extend the diagnosis of APS with other non-criteria antiphospholipid antibodies aPS/PT and anti-Annexin V. The question remains whether to investigate the whole group or only specifically. Supported by: IGA-KZ-2020-1-1 Publication History Publication Date: 18 June 2021 (online) © 2021. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany