Background The current Sydney classification criteria do not consider a range of non-thrombotic clinical manifestations that are frequently observed in association with the presence of aPLs, the so-called extra-criteria manifestations. The aim of this study was to retrospectively analysis our single center Antiphospholipid antibodies associated clinical phenotypes, especially the frequency of extra-criteria manifestations.

Methods Data of 731 serum samples from patients of clinical suspected APS in 2018 were enrolled. Data of clinical features, laboratory examination, treatment and prognosis were retrospectively analyzed.

Results A total of 200 patients with APLs were positive (27%), 56 males and 144 females, with an average age of 40.13±17.24 years, 115 cases (57.5%) with ACL positive, 167 cases (83.5%) with anti-β2GPI antibodies positive, 69 cases (34.5%) with LA positive, and 20 cases (10%) turned negative after 12 weeks without any specific therapy. 61(30.5%) patients were fulfilled the 2006 revised Sydney classification criteria for APS. One patient was Catastrophic APS. 27(44.3%) patients with primary APS, 34 (55.6%) were secondary APS, including SLE-APS (20), CTD (9), infection (3), malignancies (2). 119 patients with persistent APLs positive, but were not fulfilled the APS criteria because of without thrombosis or fetal loss. 77 (42.8%) patients were asymptomatic, 42 patients with extra-criteria manifestations. The total frequency of extra-criteria manifestations associated with APLs are 40%. The details are shown in table 1.

Conclusions The most common extra-criteria manifestations are thrombocytopenia, non-vascular neurological manifestations and valvular heart disease. And they can be the independent clinical feature of APLs without thrombotic events or Pregnancy morbidities.