Transient lupus anticoagulant presence in COVID-19 pneumonia, a probably epiphenomenon

Background : High prevalence of Lupus anticoagulant (LA) has been reported in COVID-19 infection. Aims : To determine the presence and the evolution of LA in COVID-19 pneumonia en the first 10 days at Intensive Care Unit (UCI). Methods : Prospective observational cohort study: Consecutive adult COVID-19 patients admitted to ICU. Exclusion criteria: age > 80 years, anticoagulation, tocilizumab, convalescent plasma transfusion, thrombophilia, pregnancy and cancer.Blood samples on day 1, 5 and 10 from UCI admission. Studies: PT, APTT, silica clotting time [HemosILSCT, Instrumentation laboratory(IL)], diluted Russell viper venom time HemosILDRVVT(IL) and STADRVVT(STAGO Diagnostic). Screening. Mixing with normal pooled plasma (NP) and confirmatory tests should be above their cur off points to be consider LA+. Biomarkers: D Dimer(DD), Reactive Protein C high sentitivity(cRP-H), Ferritina, LDH and interleukin 6(IL 6). Results : Patients included: 23, age 57 y (IQR52-71), 70% male, 15 required mechanical ventilation(MV).Twelve(52.1%) had LA+ by HemosILDRVVT in at least one time point, 3 in 3, 1 in 2(T5,10) and 8 in one(7/8 T1, 1/8 T5);4/5 patients with hospital discharge before T10 presented LA+ only at T1. LA prevalence was lower with STADRVVT(Table 1). SCT was negative in all samples. CRP-H, IL6 and Ferritin were higher in LA+, particularly at T5 and T10(Table 2). We cannot exclude CRP interference in DRVVT many samples had CRP > 126 (maximum concentration tested in vitro on NP). Patients received prophylactic enoxaparin, samples were taken at through, antiXa = 0.08 (0.04-0.12)U/mL, ruling out interference. LA+ was not associated with death ( n = 4) or VM requirement. Only one LA-patient developed pulmonary thromboembolism after leaving ICU. Conclusions : LA presence was demonstrated in this cohort of COVID-19 Pneumonia patients. Its presence was transient during the short period evaluated, LA was diagnosed through DRVVT with differences between regents. LA presence was associated with inflammatory biomarkers but not with MV requirement or death. These results confirm that LA is probably an epiphenomena.