TY - JOUR T1 - Response to: Correspondence on ‘Anticardiolipin and other antiphospholipid antibodies in critically ill COVID-19 positive and negative patients’ by Trahtemberg <em>et al</em> JF - Annals of the Rheumatic Diseases JO - Ann Rheum Dis DO - 10.1136/annrheumdis-2021-221780 SP - annrheumdis-2021-221780 AU - Marvin J Fritzler AU - Uriel Trahtemberg A2 - , Y1 - 2021/11/21 UR - http://ard.bmj.com/content/early/2021/11/21/annrheumdis-2021-221780.abstract N2 - We thank Dr Yudong Liu1 for commenting on our manuscript and on many of the same issues we raised.2 There are, however, some comments that require clarification and a response. It is true that antiphospholipid antibodies (aPLs) of various specificities and immunoglobulin isotypes have been reported in COVID-19.3 However, despite a historical connection of aPLs with coagulopathies and antiphospholipid syndrome (APS), to date there has been no convincing evidence that aPLs has this in vivo pathogenic effect in COVID-19. In our patients, despite the presence of aPLs (eg, IgG anticardiolipin), there was no link to thrombotic events, a finding echoed by other referenced studies4 and recently reviewed.3 5 The recent publication by Chang et al6 is mentioned, but it is important to appreciate that their results were compared with ‘normal’ controls and no clinical features (coagulopathy or APS) were reported, precluding any inferences … ER -