Background: The clinical significance of persistently positive antiphospholipid antibodies (aPLs) remains incompletely defined. Objectives: To describe the clinical and laboratory characteristics of patients with confirmed aPL positivity enrolled in the nationwide START2 Antiphospholipid Registry. Methods: Adult patients were included if all three laboratory tests-Lupus Anticoagulant (LA), anticardiolipin antibodies (aCL), and anti-β2-glycoprotein I antibodies (aβ2GPI)-were performed and confirmed after ≥12 weeks. Patients were categorized as Antiphospholipis Syndrome (APS) or aPL carriers. Clinical manifestations, non-criteria features, laboratory profiles, associated risk factors, and antithrombotic treatments were analyzed descriptively. Results: Among 500 enrolled patients, 341 were classified as APS and 159 as carriers. Women were overrepresented among carriers (76% vs 62%, p = 0.002). APS patients displayed a higher prevalence of non-criteria manifestations, largely driven by renal involvement in those with SLE. Laboratory profiles were similarly distributed across APS and carriers: triple positivity (43% vs 44%), double positivity (13% vs 12%), and isolated LA positivity (23% vs 30%). Venous thromboembolism (VTE) occurred more frequently in APS patients LA-positive only (67%, p = 0.004), while arterial thrombosis was more evenly distributed across profiles. After a first VTE, most APS patients received warfarin (62%), whereas arterial APS was treated with either warfarin (51%) or aspirin (37%). Among carriers, aspirin was the preferred prophylactic strategy (45%). Conclusions: Triple, double, and LA positive only represent the most common laboratory patterns. LA positivity omly shows a disproportionately high rate of VTE. Non-criteria manifestations remain more common in APS. Substantial variability persists in antithrombotic management, underscoring the need for prospective treatment trials.
Descriptive analysis of the Nationwide START2 antiphospholipid registry: Clinical and laboratory characteristics of patients with persistently positive antiphospholipid antibodies / Pengo, V., Poli, D., Sarti, L., Sivera, P., Barcellona, D., Prisco, D., Pizzini, A.M., Vercillo, G., Antonucci, E., Palareti, G., Start2 Antiphospholipid, R., Pignatelli, P., Menichelli, D., Pastori, D., Chistolini, A.. - In: THROMBOSIS RESEARCH. - ISSN 0049-3848. - 264:(2026). [10.1016/j.thromres.2026.109786]
Descriptive analysis of the Nationwide START2 antiphospholipid registry: Clinical and laboratory characteristics of patients with persistently positive antiphospholipid antibodies
Pignatelli, PasqualeMembro del Collaboration Group
;Menichelli, DaniloMembro del Collaboration Group
;Pastori, DanieleMembro del Collaboration Group
;Chistolini, AntonioMembro del Collaboration Group
2026
Abstract
Background: The clinical significance of persistently positive antiphospholipid antibodies (aPLs) remains incompletely defined. Objectives: To describe the clinical and laboratory characteristics of patients with confirmed aPL positivity enrolled in the nationwide START2 Antiphospholipid Registry. Methods: Adult patients were included if all three laboratory tests-Lupus Anticoagulant (LA), anticardiolipin antibodies (aCL), and anti-β2-glycoprotein I antibodies (aβ2GPI)-were performed and confirmed after ≥12 weeks. Patients were categorized as Antiphospholipis Syndrome (APS) or aPL carriers. Clinical manifestations, non-criteria features, laboratory profiles, associated risk factors, and antithrombotic treatments were analyzed descriptively. Results: Among 500 enrolled patients, 341 were classified as APS and 159 as carriers. Women were overrepresented among carriers (76% vs 62%, p = 0.002). APS patients displayed a higher prevalence of non-criteria manifestations, largely driven by renal involvement in those with SLE. Laboratory profiles were similarly distributed across APS and carriers: triple positivity (43% vs 44%), double positivity (13% vs 12%), and isolated LA positivity (23% vs 30%). Venous thromboembolism (VTE) occurred more frequently in APS patients LA-positive only (67%, p = 0.004), while arterial thrombosis was more evenly distributed across profiles. After a first VTE, most APS patients received warfarin (62%), whereas arterial APS was treated with either warfarin (51%) or aspirin (37%). Among carriers, aspirin was the preferred prophylactic strategy (45%). Conclusions: Triple, double, and LA positive only represent the most common laboratory patterns. LA positivity omly shows a disproportionately high rate of VTE. Non-criteria manifestations remain more common in APS. Substantial variability persists in antithrombotic management, underscoring the need for prospective treatment trials.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
