Factores asociados con el diagnóstico de síndrome antifosfolípido: ¿cuándo debemos solicitar los estudios?

Introduction

In clinical practice, there is no established guidance on the timing of sample collection when suspicion of antiphospholipid syndrome (APS) arises. Instead, only a list of risk factors for APS exists, without adequate quantification of the significance of each factor.

Materials and methods

Analytical observational case-control study, nested in a retrospective cohort of patients with venous or arterial thrombosis in whom APS was suspected. Patients with a confirmed diagnosis of APS according to the Sapporo criteria or triple positive initial result (cases) were compared with patients negative for APS (controls). The aim was to assess the association between the diagnosis of APS and various clinical and paraclinical factors.

Results

68 patients were included (72% women, 41.2% with deep venous thromboembolism and 29.4% with pulmonary embolism). In 18 patients APS was confirmed. There were no significant differences in age in patients with and without confirmation of the diagnosis (44.0 ± 17.9 vs. 51.2 ± 14.9, P = .069). In the multivariate analysis, a significant and independent association was found between having APS and rheumatic disease (OR: 12.1, P = .02), PTT prolongation (OR: 17.6, P = .014), platelet count < 150,000 (OR: 18.6, P = .008), and a history of previous thrombosis events (OR: 6.1 for each event, P = .027).

Conclusions

In patients with arterial or venous thrombosis, there is a greater possibility of confirming APS if there is a history of rheumatic disease, prolongation of PTT to more than 5 seconds, thrombocytopenia, and previous events of thrombotic disease. In these patients, it is advisable to screen for APS, to prevent the further occurrence of thrombotic events.