POS1238 ANTIPHOSPHOLIPID ANTIBODIES AND COVID-19: TREND OVER TIME

Abstract

Background:Since the beginning of the SARS-CoV-2 outbreak, antiphospholipid antibodies (aPL), a known thrombotic risk factor, have been studied in COVID-19 patients, in whom thromboembolic events have been associated with poor prognosis. To date, the pathogenetic role of aPL and the trend over time is still unknown.Objectives:Aim of the study was to investigate whether aPL positivity was correlated with thrombosis in COVID-19 patients and whether it was a transient or persistent.Methods:We included all consecutive COVID-19 patients hospitalized at Policlinico Umberto I, Sapienza University of Rome from April 1, 2020 to June 7, 2020. In these patients, serum levels of anti-cardiolipin (aCL) IgM, IgG, IgA, anti-β2glycoprotein I (aβ2GPI) IgM, IgG were measured by enzyme-linked immunosorbent assay (ELISA) and Lupus Anticoagulant (LA) was detected with coagulatory tests in patients not in treatment with anticoagulant drugs.Results:Five out of 73 (6.8%) patients resulted positive for aCL IgM, 3 of them also tested positive for aβ2GPI IgM. aCL IgA were tested positive in 14 out of 46 patients (30.4%). Overall 18 patients resulted positive for at least one test. Seven (9.6%) patients developed thrombotic events during hospitalization, 3 of them resulting positive for aPL (Table 1. below).Table 1.Clinical and demographic features of the 7 Covid-19 patients that presented thrombotic eventsFeaturesPatient 1Patient 2Patient 3Patient 4Patient 5Patient 6Patient 7Age - yr67788343707495SexfemalefemalefemalemalemalefemalemaleMedical HistoryMalignancy, HypertensionStrokeChronic obstructive pulmonary diseaseNo medical historyChronic obstructive pulmonary disease, HypertensionMalignancy,HypertensionInitial findingsSigns and symptomsDyspneaDyspneaDyspneaFever, ageusia/anosmia, chest painFever, coughDyspneaDyspneaHRCT chest: Bilateralground glass opacityyesyesyesyesyesyesyesBaseline laboratory valuesLymphocytecount, cells x 106/L2202102330158016806001390Lactatedehydrogenase, U/L223321199227226349199Ferritin mcg/L6143172133874622455197D-dimer mcg/L7301213291228268812981097PaO2:FIO2, mm Hg132120442534348493314Anticoagulant therapy at the time of the thrombotic eventTherapeutic dosageProphylactic dosageProphylactic dosageNot administeredTherapeutic dosageTherapeutic dosageTherapeutic dosageThrombotic eventsStrokePulmonary embolismPeripheral venous thrombosisMyocardial infarctionPulmonary embolismMyocardial infarction, peripheral arterial thrombosis, peripheral venous thrombosisPeripheral venous thrombosisAntiphospholipid antibodiesnegativeAnti-cardiolipin IgM low title, anti-β2glicoprotein I IgM low titlenegativenegativenegativeAnti-cardiolipin IgM low title, anti-β2glicoprotein I IgM low titleAnti-cardiolipin IgA low titleOutcomeExitusExitusSuicideDischargedDischargedDischargedExitusAntiphospholipid antibodies tested after at least 12 weeksNPNPNPNPNPNegativeNPWe observed that patients showing double positivity for aCL IgM and aβ2GPI IgM had a likelihood positive ratio of 6.3 for thrombotic events (p=0.012) and a likelihood positive ratio of 4.9 for increased D-dimer levels (p=0.027). aCL IgA, the most prevalent aPL in this cohort, was not associated with thrombosis. Of the 18 aPL positive patients, 5 died, 3 were lost to follow-up, and 10 were tested on a second occasion at least 12 weeks, two patients confirmed positivity without clinical signs suggestive of APS.Conclusion:These results suggest that double positivity for aCL and aβ2GPI IgM increases the risk of thrombosis in COVID-19 patients, unlike aCL IgA. APL positivity may be persistent and it is advisable to monitor it over time.Disclosure of Interests:None declared