Precision health diagnostic and surveillance network uses S gene target failure (SGTF) combined with sequencing technologies to track emerging SARS-CoV-2 variants.

INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic revealed a worldwide lack of effective molecular surveillance networks at local, state, and national levels, which are essential to identify, monitor, and limit viral community spread. SARS-CoV-2 variants of concern (VOCs) such as Alpha and Omicron, which show increased transmissibility and immune evasion, rapidly became dominant VOCs worldwide. Our objective was to develop an evidenced-based genomic surveillance algorithm, combining reverse transcription polymerase chain reaction (RT-PCR) and sequencing technologies to quickly identify highly contagious VOCs, before cases accumulate exponentially. METHODS: Deidentified data were obtained from 508,969 patients tested for coronavirus disease 2019 (COVID-19) with the TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) in four CLIA-certified clinical laboratories in Puerto Rico (n = 86,639) and in three CLIA-certified clinical laboratories in the United States (n = 422,330). RESULTS: TaqPath data revealed a frequency of S Gene Target Failure (SGTF) > 47% for the last week of March 2021 in both, Puerto Rico and US laboratories. The monthly frequency of SGTF in Puerto Rico steadily increased exponentially from 4% in November 2020 to 47% in March 2021. The weekly SGTF rate in US samples was high (>8%) from late December to early January and then also increased exponentially through April (48%). The exponential increase in SGFT prevalence in Puerto Rico was concurrent with a sharp increase in VOCs among all SARS-CoV-2 sequences from Puerto Rico uploaded to Global Influenza Surveillance and Response System (GISAID) (n = 461). Alpha variant frequency increased from <1% in the last week of January 2021 to 51.5% of viral sequences from Puerto Rico collected in the last week of March 2021. CONCLUSIONS: According to the proposed evidence-based algorithm, approximately 50% of all SGTF patients should be managed with VOCs self-quarantine and contact tracing protocols, while WGS confirms their lineage in genomic surveillance laboratories. Our results suggest this workflow is useful for tracking VOCs with SGTF.

Effect of the levonorgestrel-releasing intrauterine system on cardiovascular risk markers among women with thrombophilia or previous venous thromboembolism.

OBJECTIVE: To assess the effects of the levonorgestrel-releasing intrauterine system (LNG-IUS) on standard cardiovascular risk markers among women with thrombophilia and/or previous venous thromboembolism (VTE). METHODS: A prospective cohort study enrolled women aged 18-45 years with thrombophilia and/or a history of VTE who received the 52-mg LNG-IUS (20 µg/d initial release) at the University of Ribeirão Preto Medical School, Brazil, from January 2006 to December 2015. Before and 12 months after LNG-IUS placement, the following cardiovascular risk markers were assessed: lipid profile, body mass index (BMI), blood glucose, systolic blood pressure, diastolic blood pressure, and waist circumference. The primary outcome was changes in cardiovascular risk markers. A subanalysis of anticoagulant users versus non-users was also conducted. RESULTS: In total, 45 women were enrolled. BMI increased by 2.3% after 12 months of LNG-IUS placement (P < 0.01), but the other risk factors did not change. Cardiovascular risk markers were similar between anticoagulant users and non-users after 12 months of LNG-IUS use. CONCLUSION: Among women with thrombophilia and/or previous VTE, cardiovascular risk markers were not found to change significantly after 12 months of LNG-IUS use. The study adds safety information regarding use of the LNG-IUS for women at risk of thromboembolism.

Comparison of the hemostatic effects of a levonorgestrel-releasing intrauterine system and leuprolide acetate in women with endometriosis: a randomized clinical trial.

INTRODUCTION: The hemostatic and inflammatory systems may activate each other. Endometriosis is a chronic inflammatory disease affecting 10% of women. The objective of this study was to compare the hemostatic effects of two treatments widely prescribed to women with endometriosis: the levonorgestrel intrauterine system (LNG-IUS) and the gonadotropin-releasing hormone analog (GnRHa) leuprolide acetate. MATERIALS AND METHODS: In this randomized open-label controlled trial, 44 women with endometriosis were randomly allocated to one of two groups: 22 women were assigned to use LNG-IUS and 22 to use GnRHa. The assessed variables were D-dimers, fibrinogen, prothrombin time, activated partial thromboplastin time, coagulation factors (F) II, V, VII, VIII, IX, X, and XI, antithrombin (AT), protein C, free protein S, tissue plasminogen activator (t-PA), α2-antiplasmin, thrombin-antithrombin complex, and prothrombin fragment 1+2. All variables were assessed before treatment and six months after treatment onset. RESULTS: In the LNG-IUS group, FVIII decreased 10% after six months of use. In the GnRHa group, there was a 6% increase in AT, 29% reduction in D-dimers, and 19% increase in t-PA. The LNG-IUS users exhibited a significantly greater reduction of FVIII than the GnRHa users (LNG-IUS: -6.4 ± 14.3% vs. GnRHa: 4.2 ± 12.3%, p=0.02). The women in the GnRHa group exhibited a greater increase of AT than the LNG-IUS users (LNG-IUS: -0.7 ± 9.5% vs. GnRHa: 6.5 ± 10.1%, p=0.02). CONCLUSION: Both hormonal treatments for endometriosis exhibited no association with a procoagulant profile.

Protein S levels and the risk of venous thrombosis: results from the MEGA case-control study.

In thrombophilic families, protein S deficiency is clearly associated with venous thrombosis. We aimed to determine whether the same holds true in a population-based case-control study (n = 5317). Subjects were regarded protein S deficient when protein S levels were < 2.5th percentile of the controls. Free and total protein S deficiency was not associated with venous thrombosis: free protein S < 53 U/dL, odds ratio [OR] 0.82 (95% confidence interval [CI], 0.56-1.21) and total protein S < 68 U/dL, OR 0.90 (95% CI, 0.62-1.31). When lower cutoff values were applied, it appeared that subjects at risk of venous thrombosis could be identified at levels < 0.10th percentile of free protein S (< 33 U/dL, OR 5.4; 95% CI, 0.61-48.8). In contrast, even extremely low total protein S levels were not associated with venous thrombosis. PROS1 was sequenced in 48 subjects with free protein S level < 1st percentile (< 4 6 U/dL), and copy number variations were investigated in 2718 subjects, including all subjects with protein S (free or total) < 2.5th percentile. Mutations in PROS1 were detected in 5 patients and 5 controls reinforcing the observation that inherited protein S deficiency is rare in the general population. Protein S testing and PROS1 testing should not be considered in unselected patients with venous thrombosis.

Effects of the etonogestrel-releasing contraceptive implant inserted immediately postpartum on maternal hemostasis: a randomized controlled trial.

INTRODUCTION: The puerperium is the period of highest risk for thrombosis during a woman's reproductive life and it is an important time for initiating an effective contraceptive method in order to increase intergestational interval. Thus, the objective of the present study was to evaluated the effects of the etonogestrel (ENG)-releasing contraceptive implant inserted immediately postpartum on maternal hemostasis markers during the first six weeks of delivery. MATERIALS AND METHODS: Forty healthy women aged 18 to 35 years-old were randomized to receive either the ENG-releasing implant 24-48 h after delivery (implant group; n=20) or nothing (control group) until the sixth postpartum week. Blood samples were collected at 24-48 h and at 6 weeks after delivery, and hemostatic variables, including fibrinogen, coagulation factors, protein C, free protein S, antithrombin, α2-antiplasmin, plasminogen activator inhibitor 1, thrombin-antithrombin complex (TAT), prothrombin fragment (PF)1+2, and D-dimers, as well as normalized activated protein C sensitivity ratio (nAPCsr), thrombin time, activated partial thromboplastin time, and prothrombin time were evaluated. RESULTS: Insertion of the ENG-releasing contraceptive implant did not change the physiological reduction in overall coagulation (TAT and PF1+2) and fibrinolysis (D-dimer) markers, or nAPCsr. Reductions in factors II, VII, X and fibrinogen and increases in factor V were greater in the control than in the implant group. Clotting factors remained within normal limits throughout the study. CONCLUSION: The ENG-releasing contraceptive implant inserted immediately postpartum did not have negative effects on physiological variations of the hemostatic system during the first 6 weeks postpartum.

Anticoagulação em pacientes hospitalizados / Anticoagulation in hospitalized patients

Os eventos tromboembólicos, principalmente o tromboembolismo venoso, acrescem importante morbidade e mortalidade e representam a segunda causa mais comum de complicações em pacientes hospitalizados. A anticoagulação é o tratamento padrão nestes casos, porém frequentemente seu manejo é complexo e requer conhecimento adequado tanto da farmacologia das drogas quanto da fisiologia da coagulação. Este artigo revê alguns pontos essenciais para quem lida com esses eventos e fornece noções práticas do manejo dos antagonistas da vitamina K e dos anticoagulantes parenterais.

Thromboembolic events, particularly venous thromboembolism, add significant morbidity and mortality and represent the second most common cause of complications in hospitalized patients. Anticoagulation is the standard treatment in these cases, but often their management is complex and requires adequate knowledge of both the pharmacology of drugs and the physiology of coagulation. This article reviews some key points to those who deal with these events and provides practical notions of management of vitamin K antagonists and parenteral anticoagulants.

VKORC1 and the vitamin K cycle.

Vitamin K epoxide, a product of gamma-carboxylation, must be rapidly recycled to its reduced form before it can be reused. The set of sequential reactions that guarantees vitamin K recycling is known as the vitamin K cycle. This review is focused on biochemical and genetic aspects of a recently characterized key enzyme of the cycle named vitamin K epoxide reductase complex subunit 1 (VKORC1). This 163-amino acid long protein (18 kDa) is responsible for vitamin K reduction. Recent studies also demonstrated the existence of a VKOR complex in which protein disulfide isomerase (PDI) and VKORC1 appear to be tightly associated. PDI is a thioredoxin-like oxidoreductase and chaperone that is present at high concentrations in the endoplasmic reticulum (ER) and that provides electrons for reduction of the CXXC center in VKORC1. Genetic studies have shown that the VKORC1 gene extends over 5126 base pairs on human chromosome 16 and comprises three exons. Mutations in the VKORC1 gene causes generalized defective vitamin K-dependent clotting factors (VKCFD2) and warfarin resistance (WR). More detailed pharmacogenetic studies have demonstrated a strong association between single nucleotide polymorphisms (SNPs) in the VKORC1 gene and the requirement of warfarin dosage. Screening for VKORC1 polymorphisms that affect warfarin dosage could be helpful to tailor dosage at the onset of oral anticoagulant treatment in order to lower thrombosis and bleeding risks.

Tratamento de distúrbios hemostáticos em urgência médica / Management of hemostatic disorders in the emergency room

Patologias do sistema hemostático são causas freqüentes de atendimento médico de urgência. Este texto revisa aspectos relevantes no que diz respeito a diagnóstico e tratamento de hemofilias e coagulação intravascular disseminada (CIVD)

Trombofilias adquiridas / Acquired thrombophilias

Na presente revisäo, discutimos a contribuiçäo de fatores de risco adquiridos para a ocorrência de tromboembolismo venoso