No abstract

COVID-19 is an infection induced by the SARS-CoV-2 coronavirus, and severe forms can lead to acute respiratory distress syndrome (ARDS) requiring intensive care unit (ICU) management. Severe forms are associated with coagulation changes, mainly characterized by an increase in D-dimer and fibrinogen levels, with a higher risk of thrombosis, particularly pulmonary embolism. The impact of obesity in severe COVID-19 has also been highlighted.In this context, standard doses of low molecular weight heparin (LMWH) may be inadequate in ICU patients, with obesity, major inflammation, and hypercoagulability. We therefore urgently developed proposals on the prevention of thromboembolism and monitoring of hemostasis in hospitalized patients with COVID-19.Four levels of thromboembolic risk were defined according to the severity of COVID-19 reflected by oxygen requirement and treatment, the body mass index, and other risk factors. Monitoring of hemostasis (including fibrinogen and D-dimer levels) every 48 h is proposed. Standard doses of LMWH (e.g., enoxaparin 4000 IU/24 h SC) are proposed in case of intermediate thrombotic risk (BMI < 30 kg/m2, no other risk factors and no ARDS). In all obese patients (high thrombotic risk), adjusted prophylaxis with intermediate doses of LMWH (e.g., enoxaparin 4000 IU/12 h SC or 6000 IU/12 h SC if weight > 120 kg), or unfractionated heparin (UFH) if renal insufficiency (200 IU/kg/24 h, IV), is proposed. The thrombotic risk was defined as very high in obese patients with ARDS and added risk factors for thromboembolism, and also in case of extracorporeal membrane oxygenation (ECMO), unexplained catheter thrombosis, dialysis filter thrombosis, or marked inflammatory syndrome and/or hypercoagulability (e.g., fibrinogen > 8 g/l and/or D-dimers > 3 μg/ml). In ICU patients, it is sometimes difficult to confirm a diagnosis of thrombosis, and curative anticoagulant treatment may also be discussed on a probabilistic basis. In all these situations, therapeutic doses of LMWH, or UFH in case of renal insufficiency with monitoring of anti-Xa activity, are proposed.In conclusion, intensification of heparin treatment should be considered in the context of COVID-19 on the basis of clinical and biological criteria of severity, especially in severely ill ventilated patients, for whom the diagnosis of pulmonary embolism cannot be easily confirmed.

No abstract

Patients with SLE and LA are at approximately six times greater risk for VT than patients without LA, whereas patients with SLE and aCL are approximately two times greater risk for VT than patients without aCL. We have identified important methodologic limitations and differences in study characteristics. Other risk factors for VT have not been thoroughly evaluated in these studies. Further studies are needed that provide an accurate estimate of the absolute risk for aPL related VT.

No abstract

Background-Heart valve disease (HVD) is frequent in patients with systemic lupus erythematosus (SLE), and the role of antiphospholipid antibodies (aPL) is controversial. Thus, our objective was to estimate the risk of HVD, including Libman-Sacks endocarditis, associated with aPL in patients with SLE. Methods and Results-Studies were selected if they investigated the association between aPL and HVD in SLE patients and if aPL-negative patients were included for comparison. Data sources were MEDLINE, Embase, Cochrane Library, hand search, contact with investigators, and reference lists of studies, without language restrictions. Data on study and patient characteristics, risk estimates, and study quality were independently extracted by 2 investigators. Pooled effect estimates were obtained by using the DerSimonian-Laird method. Of 234 identified abstracts, 23 primary studies (15 cross-sectional, 7 cohort, 1 case-control) met inclusion criteria, including 1656 SLE patients and 508 cases of HVD. Compared with SLE patients without aPL (nϭ988), the overall pooled odds ratios for HVD and Libman-Sacks endocarditis in aPL-positive patients (nϭ668) were 3.13 (95% confidence interval, 2.31 to 4.24) and 3.51 (95% confidence interval, 1.93 to 6.38), respectively. The risk of HVD depending on aPL subtypes was the highest for lupus anticoagulant at 5.

To cite this article: Trossaë rt M, Regnault V, Sigaud M, Boisseau P, Fressinaud E, Lecompte T. Mild hemophilia A with factor VIII assay discrepancy: using thrombin generation assay to assess the bleeding phenotype. J Thromb Haemost 2008; 6: 486-93.

Patients with systemic lupus erythematosus (SLE) and antiphospholipid antibodies (aPL) are at a greater risk for venous thromboembolism (VTE) than SLE patients without these antibodies. For patients without SLE there is a controversy about the risk associated with these antibodies and about their prognostic significance. We reviewed the degree of evidence and describe the odds ratio for VTE associated with aPL, namely the lupus anticoagulant (LA) and anticardiolipin antibodies (aCL), in patients without SLE. The study was a meta-analysis of seven observational studies of risk for antiphospholipid associated venous thromboembolism (VTE), excluding SLE patients. The strategies to identify published research included a computerized literature search and the review of citations in primarily relevant articles for the period 1983 to 1997. A summary of study characteristics and a critical appraisal of study quality were done. Summary odds ratios were obtained conducted using a random and a fixed effects-model. The overall odds ratio for aCL associated VTE obtained by fixed-effects model was 1.56 (95% CI, 1.10-2.24) and 1.64 (95% CI, 0.93-2.89) by random-effects model. The heterogeneity of these results appeared to be due in part to the detection limit of the aCL assay: the odds ratio was 3.21 (95% CI, 1.11-9.28) with both models when high titres only were considered. The overall odds ratio for LA associated VTE was 11.1 (95% CI, 3.81-32.3). In conclusion meta-analysis of the risk for antiphospholipid associated thrombosis demonstrated a higher risk in patients with the LA than in other patients. This risk was also higher than in patients with aCL even when high titres only were considered.