Antibodies to the phosphatidylserine/prothrombin complex in the diagnosis of antiphospholipid syndrome

Abstract

Aim. To determine the significance of antibodies to the phosphatidylserine/prothrombin complex (aPS/PT) in patients with systemic lupus erythematosus (SLE) antiphospholipid syndrome (APS).
 Materials and methods. A total of 190 patients were included in the study: 123 (64.7%) with reliable SLE and 55 (29%) with PAPS. The control group included 100 relatively healthy subjects of comparable age. All patients were tested for classical aPL as well as IgG/IgM-anti-PS/PT by enzyme immunoassay.
 Results. Based on the average values of IgG/IgM aPS/PT of the control group, the levels of positivity were allocated mean (M) + 3 or 5 standard deviations (SD): M+3SD and M+5SD. IgG aPS/PT levels above 73.6 U/ml (M+5SD) were more accurate diagnostic, for IgM aPS/PT above 18.0 U/ml. IgG-aPS/PT were detected in 84 (44%) of 190 patients. Levels above diagnostic levels were detected in 68 (65%) of 104 patients with APS (55 with PAPS and 59 with SLE+APS). Thrombosis was significantly more common in patients with IgG aPS/PT compared with patients negative for IgG aPS/PT. Arterial but not venous thrombosis was associated with IgG aPS/PT positivity.
 Conclusion. The frequency of detection of IgG aPS/PT in the examined patients was 44%, IgM aPS/PT 29% and their combination 19% of 190 patients. Half of the patients with probable APS had positive IgG aPS/PT and third IgM aPS/PT. Median IgG aPS/PT were significantly higher in patients with APS compared to patients without APS and the control group. Thrombosis was associated with IgG aPS/PT. Arterial thrombosis was significantly more frequently reported in patients with IgG aPS/PT. The sensitivity of IgG aPS/PT for reliable APS at levels greater than 73.6 units/ml was 59%, specificity 92%, for IgM aPS/PT 35% and 91%, respectively.

Research trends and frontiers on antiphospholipid syndrome: A 10-year bibliometric analysis (2012–2021)

“…Several studies have demonstrated a link between the IgA isotypes and thrombosis (Pericleous et al, 2016;Tebo et al, 2016). Recently, Reshetnyak et al reported that IgA aCL and IgA aβ2GPI had a high specificity (95% and 93%) but a low sensitivity (54% and 44%) in detecting APS (Reshetnyak et al, 2022). The diagnostic value of IgA aPL is worthy of further study in the future.…”