Discriminatory accuracy of the SOFA score for determining clinical decompensation in patients presenting with COVID-19

Introduction

While the global dissemination of vaccines targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a decline in the incidence of infections, the case fatality rates have remained relative stable. A major objective of managing hospitalized patients with documented or suspected COVID-19 infection is the rapid identification of features associated with severe illness using readily available laboratory tests and clinical tools. The sequential organ failure assessment (SOFA) score is a validated tool to facilitate the identification of patients at risk of dying from sepsis.

Purpose

The aim of this study was to assess the discriminatory accuracy of the SOFA score in predicting clinical decompensation in patients hospitalized with COVID-19 infection.

Methods

We conducted a retrospective analysis at a three-hospital health system, comprised of one tertiary and two community hospitals, located in the Chicago metropolitan area. All patients had positive SARS-CoV-2 testing and were hospitalized for COVID-19 infection. The primary outcome was clinical decompensation, defined as the composite endpoint of death, ICU admission, or need for intubation. We utilized the most abnormal laboratory values observed during the admission to calculate the SOFA score. Receiver Operating Curves (ROC) were then constructed to determine the sensitivity and specificity of SOFA scores.

Results

Between March 1st and May 31st 2020, 1029 patients were included in our analysis with 367 patients meeting the study endpoint. The median SOFA score was 2.0 IQR (Q1, Q3 1,4) for the entire cohort. Patients who had in-hospital mortality had a median SOFA score of 4.0 (Q1,Q3 3,7). In patients that met the primary composite endpoint, the median SOFA score was 3.0, IQR (Q1, Q3 2,6). The ROC was 0.776 (95% CI 0.746–0.806, p<0.01).

Conclusion

The SOFA score demonstrates strong discriminatory accuracy for prediction of clinical decompensation in patients presenting with COVID-19 at our urban hospital system.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Loyola University Medical Center

Predictors of clinical decompensation in patients presenting with COVID-19 in an urban hospital health system

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a pandemic which has infected more than 128 million people and led to over 2.8 million deaths worldwide. Although the introduction of efficacious vaccines has led to overall declines in the incidence of SARS-CoV-2 infection, there has been a recent increase in infections once more due to the appearance of mutant strains with higher virulence. It therefore remains vital to identify predictors of poor outcomes in this patient population.

Purpose

The objective of our study was to identify predictors of prolonged hospitalization, intensive care unit (ICU) admission, intubation, and death in patients infected with SARS-CoV-2.

Methods

We conducted a retrospective analysis of all patients hospitalized with SARS-CoV-2 at our health system that includes one tertiary care center and two community hospitals located in the Chicago metropolitan area. The main outcome was a composite endpoint of hospitalization >28 days, ICU admission, intubation, and death.

Explanatory variables associated with the primary outcome in the bivariate analysis (p<0.05) were included in the multivariable logistic regression model. Statistical analysis was performed using IBM SPSS 25.0.

Results

Between March 1, 2020 and May 31, 2020, 1029 patients hospitalized with SARS-CoV-2 were included in our analysis. Of these patients, 379 met the composite endpoint. Baseline demographics are described in Table 1. Of note, our cohort consisted of a predominantly minority patient population including 47% Hispanic, 17% African American, 16% Caucasian, and 16% other.

In bivariate analysis, age, hypertension, tobacco and alcohol abuse, obesity, coronary artery disease, arrhythmias, valvular heart disease, dyslipidemia, hypertension, stroke, diabetes, documented thrombosis, troponin, CRP, ESR, ferritin, LDH, BNP, D-dimer >5x the upper limit of normal, lactate, and right ventricular outflow tract velocity time integral <9.5 were significant.

After multivariable adjustment, explanatory variables associated with the composite endpoint included troponin (OR 2.36; 95% CI 1.08–5.17, p 0.03), D-dimer (OR 1.5; 95% CI 1.23–1.98, p<0.01, lactate (OR 1.58; 95% CI 1.28–1.95, p<0.01), and documented thrombosis (OR 3.56; 95% CI 1.30–8.70, p<.05). Race was not a predictor of poor outcomes in the bivariate or multivariate analysis (Table 2).

Conclusions

In a large urban cohort with a predominantly minority population, we identified several clinical predictors of poor outcomes. Of note, race was not a predictor of the primary endpoint in this study. While recent literature has demonstrated worse outcomes among racial minorities infected with SARS-CoV-2, our data suggests these variations are related to social determinants of health rather than biologic causes.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Loyola University Medical Center

Factor Xa Inhibitors in the Control of Thrombogenesis

It is now well recognized that drugs with sole anti-Xa activity are capable of producing antithrombotic effects. The basic and clinical studies with pentasaccharide have validated this hypothesis. Synthetic heparin pentasaccharide is currently undergoing clinical trials in the prophylaxis of DVT in orthopedic surgery. While the naturally occuring direct anti-Xa agents such as antistatin, TAP and Yagin are potent anti-Xa agents their clinical development is delayed due to several unresolved developmental issues. On the other hand, several peptidomi-metic agents also demonstrate varying degrees of oral and subcutaneous bioavailability. One of these agents namely the DX 9065a is in clinical trials at this time. The factor Xa inhibitors exhibit a higher margin of safety in contrast to the antithrombin agents, however, their anticoagulant effects are somewhat weaker than the antithrombin agents. Thus, these agents may prove to be very useful in the prophylactic management of both the thrombotic and cardiovascular disorders. However, their use as an anticoagulant may not be very practical. These agents can be given as adjunct agents with hirudin and related antithrombin agents. These agents may also be of value in the outpatient management of thrombotic disorders. These agents may also be of value as an adjunct to various other antithrombotic drugs. Additional adjunct uses as with the antithrombin drugs, GP llb/llla inhibitors, thrombolytic agents and TFPI may increase the therapeutic index of many of these agents. It should be emphasized that each of these individual anti-Xa agents represent distinct drugs which require individual specific dosage optimization.

Combined Thrombin and Platelet Inhibition Treatment for HIT Patients

Despite the use of potent anticoagulants such as r-hirudin and argatroban, the morbidity and mortality in heparin-induced thrombocytopenia (HIT) patients remains unacceptable. Data from our in vitro investigations show that thrombin inhibitors do not block platelet activation induced by heparin antibodies and heparin but that GPIIb/IIIa receptor inhibitors do block this process. We have treated four HIT positive patients with a combined therapy of thrombin inhibitor and GPIIb/IIIa receptor inhibitor when treatment with thrombin inhibitor alone failed to alleviate acute thrombosis. Combination therapies included r-hirudin (Refludan®) with tirofiban (Aggrastat®) and argatroban (Novastan®) with abciximab (ReoPro®). A reduced dose of the thrombin inhibitor was used with the standard dose of the anti-platelet drug. In all cases, there was no overt bleeding which required intervention, and all patients exhibited clinical improvement or full recovery. These case studies suggest that treatment of active thrombosis in HIT patients with adjunct GPIIb/IIIa receptor inhibitor therapy may be more effective than thrombin inhibitor treatment alone.

A Perspective on Low Molecular Weight Heparins in the Management of Thrombosis

The introduction of low molecular weight heparins has added a new dimension to the pharmacological management of thrombotic disorders. Because of different chemical and pharmacological characteristics, due to the manufacturing process, each LMWH should be considered as a distinct entitity and only be used for its given indication. A list of commercially available LMWHs is included. The mechanism of action of the LMWHs and their use in various disorders are discussed. Available laboratory tests for monitoring LMWHs are presented and their limitations pointed out.

Influence of Different Anticoagulant Agents on Fibrinopeptide A Generation

The purpose of this study was to determine the in vitro effects of different anticoagulant drugs on fibrinopeptide A (FPA) generation inhibition and to identify whether there is any correlation between FPA generation, Hemochron ACT, global clotting as says, and chromogenic assays. Unfractionated heparin is a conventionally used anticoagulant. New anticoagulant drugs such as low molecular weight heparins (LMWHs), pentasaccharide, and antithrombin drugs are now approved for various indications. Anti-Xa drugs are in various phases of clinical development. The influence of different anticoagulant agents has been studied on fibrinopeptide A generation, Hemochron celite ACT, global clotting assays, and chromogenic anti-Xa and anti-Ila assays. Different LMWHs (Clivarin, Dalteparin, Enoxaparin, and Tinzaparin), anti-Xa agents (Pentasaccharide, DX-9065a and unfractionated heparin), and anti-Ila agents (PEG-Hirudin, Hirudin, Efegatran and Argatroban) were studied. The blood from healthy volunteers (n=4) was drawn for each drug. Imuclone FPA enzyme-linked immunosorbent kit assay, Hemochron celite ACT assay, global clotting assays (PT, APTT, Heptest-HI, thrombin time), and Loyola chromogenic anti-Xa and anti-Ila assays were studied. Pentasaccharide demonstrated minimal effects on the whole blood clotting time such as ACT and on inhibition of FPA generation (IC50 > 25 /g/mL). DX-9065a exhibited a significant prolongation of ACT and marked inhibition of FPA generation (IC50 = 4.12 Ag/mL). Unfractionated heparin showed a marked inhibition of FPA generation (IC,, = 5.16 Aog/mL). Pentasaccharide, DX-9065a and UFH showed a marked correlation between ACT and inhibition of FPA generation. LMWHs demonstrated concentrationdependent inhibition of FPA generation. LMWHs studied showed good correlation between FPA generation inhibition and ACT test. Similar correlation was seen between FPA generation inhibition and the APTT, anti Xa (heptest-HI assay) and anti-IIa activity. Anti-IIa drugs demonstrated concentration-dependent inhibition of FPA generation. Their FPA generation inhibition potency is correlated with the ACT assay. A strong correlation between Hemochron ACT and FPA generation inhibition was observed. Based on this significant correlation, the FPA generation inhibition can be predicted by point-of-care ACT assay.

Blood Levels of Nitric Oxide, C-Reactive Protein, and Tumor Necrosis Factor-α Are Upregulated in Patients with Malignancy-Associated Hypercoagulable State: Pathophysiologic Implications

Endogenous generation of nitric oxide (NO) plays an important role in the regulation of cardiovascular and inflammatory responses. This mediator is synthesized by a family of enzymes collectively known as NO synthase. Several isoforms of this enzyme have been identified and can be grouped as constitutive or inducible. Increased production of NO is reported in several inflammatory disorders, such as sepsis, arthritis, thrombotic thrombocytopenic purpura (TTP), and antiphospholipid syndrome. In addition, NO upregulates cyclo-oxygenase-2 and synthesis of several other inflammatory cytokines. Inflammation and thrombotic complications are usually associated with malignancy. Earlier reports indicate the upregulation of tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and tissue factor (TF) in patients with malignancy. To determine the relationship between inflammatory cytokines and NO in cancer patients with hypercoagulable states, baseline plasma samples from 160 patients with confirmed malignancy and hypercoagulable state were analyzed for NO levels. A chemical method based on a chemiluminescent reaction between NO and ozone using a highly sensitive gas phase NO analyzer was used. CRP, TF, and TNF-α were measured using enzyme-linked immunosorbent assay methods. Of the 160 patients who were plasma tested, the baseline NO levels ranged from 13.7 to 98.6 μM (63.1±15.9 μM, mean±SD) in contrast to age-matched control, which ranged from 9.1 to 34.6 μM (19.8±6.2 μM, mean±SD, n=138). Cancer patients also showed marked variations in the NO levels. Eighteen of 60 cancer patients exhibited greater than 60 μM NO levels. The CRP, TNF-α and TF were also significantly elevated. A correlation between CRP (r2=0.73) and NO levels was noted in cancer patients with hypercoagulable state. These data suggest that the pathogenesis associated with malignancy/hypercoagulable state is associated with an inflammatory component. In addition, the observed hemodynamic changes in some of the cancer patients may be due to increased NO production.

In vitro Simulation of Therapeutic Plasmatic Fibrinolysis

One type of therapy for thromboembolism is plasmatic thrombolysis. Several plasminogen activators (PA) are clinically available, including urokinase (u-PA), tissue plasminogen activator (t-PA), streptokinase (SK), plasminogen-streptokinase-activator-complex (PSAC), or mutants of t-PA such as reteplase (RP) or tenecteplase (TP). Therapeutic plasmatic fibrinolysis was simulated, using the PA at relevant plasma concentrations, and plasmin (Pli) and PA activities were determined. Normal citrated plasma was supplemented with 31 to 1,000 IU/mL u-PA, 0.31 to 20 μg/mL t-PA, 125 to 4,000 IU/mL SK, 12.5 to 400 U/mL PSAC, 125 to 4,000 U/mL RP, or 0.31 to 10,μg/mL TP. Ten IU/mL urokinase was also incubated with pooled plasma of stroke patients, that was previously oxidized with the singlet oxygen (1O2) donor chloramine T® (CT), to destroy plasmatic PAI-1 and a2-antiplasmin. After 0 to 80 minutes (37°C), 50-μL samples were withdrawn and added to 100 μL 1.5 M arginine, pH 8.7, and oxidized with 50 μL of 20 mM CT. For determination of plasmin activity, 10 μL thereof was incubated with 150 μL 1.5 M arginine, pH 8.7, and 100 μL 20 mM CT preoxidized (15 minutes 37°C) pooled normal citrate buffered EDTA-plasma for 30 minutes (37°C). For determination of [PA+Pli]-activity, arginine was added after this incubation. 25-μL 6 mM Val-Leu-Lys-pNA were added and AA/h at room temperature (RT) was monitored, using a microtiterplate reader. [PA+Pli]-Pli = PA. The PA concentration required to induce 25% [ED25] of the maximally inducible Pli-activity in plasma (= 1 U/mL = 45 mg/L = 0.53 Amol/L active Pli; AA = 363 + 8 mA/h RT) after 10 minutes (37°C) were 320 IU/mL u-PA, 8 μg/mL t-PA, 140 U/mL PSAC, 6,000 IU/mL SK, 720 U/mL RP, and approximately 150 μg/mL TP. The approximate activity half-lives of the PA in plasma were 30 minutes for u-PA, 30 minutes for t-PA, greater than 80 minutes for SK, greater than 80 minutes for PSAC, 50 minutes for RP, and 80 minutes for TP. The present study shows-for the first time-a combined kinetic in vitro simulation of the plasmatic activity of six different PAs. At clinically used concentrations, RP induces the highest plasmatic Pli activity. Due to unselective generation of plasmin in plasma, all PA are of some danger in inducing severe hemorrhagias. Clinical thrombolysis might be improved by usage of more physiologic activators of thrombolysis, such as activators of polymorphonuclear neutrophils.

Elevated endocan levels and its association with clinical severity in Stevens-Johnson Syndrome and toxic epidermal necrolysis

AIM

The aim of this study was to determine the levels of endocan and other biomarkers of inflammation in the systemic circulation of three groups of patients: 1) biopsy confirmed Stevens Johnson Syndrome, Toxic Epidermal Necrolysis (SJS/TEN) subjects; 2) patients with allergic skin reactions but biopsy negative for SJS/TEN; and 3) normal controls. Besides, this paper aims to investigate the association of endocan levels with the extent of the skin lesions, the presence of purpura, and the degree of acute renal insufficiency, as well as to investigate endocan as a marker of clinical severity by correlating endocan levels with the SCORTEN results (a prognositic score for SJS/TEN).

METHODS

Sixteen patients over the age of 18 years who were referred to Loyola University Medical Center with severe allergic skin reactions were recruited over a two-year period from May 2012 to May 2014. A diagnosis of SJS or TEN was confirmed in 7 subjects by skin biopsy. Citrated plasma samples were assayed for endocan, tumor necrosis factor-α (TNFα), vascular endothelial growth factor (VEGF), and C-reactive protein (CRP). The differences between SJS/TEN subjects, biopsy negative subjects, and normal controls (N.=23) were explored using ANOVA and Tukey's post-hoc test. Associations with other clinical variables were identified using linear and logistic regression.

RESULTS

Biopsy positive SJS/TEN subjects and biopsy negative subjects had higher endocan levels than normal controls (SJS/TEN: 3.01 ng/mL [IQR: 2.15-8.11]; biopsy negative: 3.96 ng/mL [IQR: 1.54-4.85]; normal controls: 1.79 ng/mL [IQR: 1.67-1.98]; ANOVA P=0.0038). Endocan levels were more strongly associated with SCORTEN in SJS/TEN subjects than in biopsy negative subjects (R2 SJS/TEN=0.5110; biopsy negative=0.0317). SJS/TEN subjects exhibited significantly higher levels of TNF-α compared to normal controls (P=0.0267). The TNF-α levels were significantly lower compared to biopsy negative subjects (P=0.0052). VEGF levels were also elevated among SJS/TEN and biopsy negative subjects compared to normal controls (SJS/TEN: 12.04 pg/mL: [IQR: 7.64-52.7]; biopsy negative: 10.54 pg/mL [IQR: 4.17-6.46]; normal controls: 4.94 pg/mL [IQR: 4.17-6.46]; ANOVA P<0.0001). There was no significant difference in VEGF levels between SJS/TEN and biopsy negative subjects (P=0.7110). Similarly, CRP levels were elevated among SJS/TEN patients and biopsy negative subjects compared to normal controls (SJS/TEN: 32.09 µg/mL [IQR: 31.49-52.08]; biopsy negative: 83.38 µg/mL [IQR: 44.74-145.38]; healthy normal: 1.08 µg/mL [IQR: 0.73-2.03]; ANOVA P<0.0001). There was no significant difference in CRP levels between SJS/TEN and biopsy negative subjects (P=0.2416).

CONCLUSION

To our knowledge, this is the first study to evaluate enodcan, a marker of endothelial dysfunction, in the systemic circulation of SJS/TEN patients. Elevated endocan levels were more strongly associated with disease severity among SJS/TEN subjects than among less severe allergic reactions with skin involvement.

Medical management of patients with peripheral arterial disease

Peripheral arterial disease (PAD) is one of the most frequent manifestations of atherosclerosis and is associated with atherosclerosis in the coronary and carotid arteries, leading to a highly increased incidence of cardiovascular events. Major risk factors of PAD are similar to those that lead to atherosclerosis in other vascular beds. However, there are differences in the power of individual risk factors in the different vascular territories. Cigarette smoking and diabetes mellitus represent the greatest risks of PAD. For prevention of the progression of PAD and accompanying cardiovascular events similar preventative measures are used as in coronary artery disease (CAD). However, recent data indicate that there are some differences in the efficacy of drugs used in the prevention of atherothrombotic events in PAD. Antiplatelet treatment is indicated in virtually all patients with PAD. In spite of the absence of hard evidence- based data on the long term efficacy of aspirin, it is still considered as a first line treatment and clopidogrel as an effective alternative. The new antiplatelet drugs ticagrelol and prasugrel also represent promising options for treatment of PAD. Statin therapy is indicated to achieve the target low density lipoprotein cholesterol level of ≤2.5 mmol/L (100 mg/dL) and there is emerging evidence that lower levels are more effective. Statins may also improve walking capacity. Antihypertensive treatment is indicated to achieve the goal blood pressure (<140/90 mmHg). All classes of antihypertensive drugs including beta-blockers are acceptable for treatment of hypertension in patients with PAD. Diabetic patients with PAD should reduce their glycosylated haemoglobin to ≤7%. As PAD patients represent the group with the highest risk of atherothrombotic events, these patients need the most intensive treatment and elimination of risk factors of atherosclerosis. These measures should be as comprehensive as those in patients with established coronary and cerebrovascular disease.

Pharmacological profile of sulodexide

Since its introduction, sulodexide has been used on and off for several indications. More recently this agent has become revitalized and tested in newer indications. Sulodexide is composed of glycosaminoglycan that includes a mixture of fast-moving heparin and dermatan sulfate. It exerts its anticoagulant and antithrombotic action through interactions with both AT and HCII. Sulodexide has been proven to have effects on the fibrinolytic system, platelets, endothelial cells, inflammation and more recently metalloproteases. The administration of sulodexide results in the release of lipoprotein lipase and has been shown to reduce the circulating level of lipids. It has also shown to decrease the viscosity of both whole blood and plasma. Sulodexide differs from heparin in its oral bioavailability and longer half-life. There is also less bleeding associated with sulodexide. In addition, oral administration of sulodexide does not interfere with the pharmacologic actions of commonly used agents. Similar to heparin, sulodexide releases TFPI which contributes to its antithrombotic effect and anti-inflammatory properties. Sulodexide has been proven to be effective in peripheral arterial thrombosis and venous thrombosis. It is also clinically active in the treatment of venous leg ulcers and intermittent claudication. More recent data suggest that sulodexide can be used in tinnitus and in vascular vertigo. Additional studies in these indications are required. Sulodexide was generally safe and well tolerated in the clinical trials, without any severe bleeding complications. Therefore sulodexide appears to be a good treatment for all arterial and venous diseases and for the prevention of progression of disease.

Association between serum levels of pro-metalloproteinase 1, tissue inhibitor of metalloproteinases 1 and 2 and prevalent cardiovascular disease in a population-based study

AIM

The aim of the study was to test the association between circulating levels of matrix prometalloproteinase1 (pro-MMP1) and its tissue inhibitors TIMP1 and TIMP2 with prevalent cardiovascular events.

METHODS

Prevalent cardiovascular events were documented in 500 participants of the Cyprus study (46% men) over the age of 40. Serum levels of pro-MMP1, TIMP1 and TIMP2 were measured with ELISA and the association between quartiles of serum levels and presence of cardiovascular disease (CVD) was tested using multivariable binary regression models.

RESULTS

Lower serum levels of pro-MMP1 and TIMP1 were strongly associated with presence of CVD at baseline even after adjustment for conventional risk factors (P(for trend)=0.006 and P=0.001, respectively) and inflammatory factors (P(for trend)=0.005 and P=0.002, respectively) with people in the highest quartile of pro-MMP1 having a reduced odds for cardiovascular disease by about 70% compared to the lowest quartile (OR(adjusted)=0.26; 95% CI=0.19 to 0.75; P=0.01), whereas people with TIMP1 levels >1000 ng/mL had a 75% reduced odds for CVD compared to the rest (OR(adjusted)=0.25; 95% CI=0.11 to 0.60; P(for trend)=0.002). TIMP2 levels were not associated with prevalent cardiovascular disease.

CONCLUSION

A strong association between lower levels of circulating pro-MMP1 and TIMP1 and risk of prevalent cardiovascular disease in a general population cohort over 40 years is evident, independent from common cardiovascular and inflammatory risk factors. The role of MMP1 and its tissue inhibitors, should be tested further in prospective studies of cardiovascular disease.

Prevention and treatment of venous thromboembolism--International Consensus Statement

The aim of this document is to provide a clear and concise account of the evidence regarding efficacy or harm for various methods available to prevent and manage venous thromboembolism (VTE).

Thromboelastographic evaluation of blood coagulation in the presence of branded and generic enoxaparins

AIM

Enoxaparin is the most widely used low-molecular-weight heparin (LMWH) in the USA and has been approved for clinical use in multiple indications. Enoxaparin is a complex biological product with multiple known activities relevant to its antithrombotic effects, and variations in different forms of enoxaparin may have important clinical implications. This study aimed to compare the physiological anticoagulant activity of branded and a generic enoxaparin, using thromboelastography (TEG) to evaluate their effect on the dynamic formation of the blood clot as quantitated by interactions between coagulation factors and inhibitors, fibrinogen, platelets and the fibrinolytic system.

METHODS

Whole native (no preservative) blood was obtained from 7 healthy volunteers. Samples were immediately mixed with various concentrations of branded or generic enoxaparin and TEG was performed to assess anticoagulant activity. Five different batches of each enoxaparin (branded and generic) were tested.

RESULTS

Generic enoxaparin showed more variation in anticoagulation response with a less predictable concentration-dependent and linear response compared with branded enoxaparin. There was also an apparent batch-to-batch variation for generic enoxaparin. The results demonstrated a lower overall anticoagulant effect (P=0.05; no overlap of 95% confidence intervals) with a wider inter-individual variation for generic enoxaparin in comparison with branded enoxaparin. Some individuals responded with a higher than expected anticoagulant response to the given concentration of the generic enoxaparin.

CONCLUSION

The findings of this study suggest that other pre-clinical and clinical studies should be done to validate the clinical interchangeability between branded and generic enoxaparin.

Defibrotide blunts the prothrombotic effect of thalidomide on endothelial cells

Patients with multiple myeloma (MM) are at relatively high risk of developing thromboembolic events such deep venous thrombosis (DVT) where thalidomide therapy has been identified to increase this risk. Defibrotide (DF), a polydisperse oligonucleotide, showed previously to counteract the alterations in endothelial cells (ECs) induced by lipopolysaccharide. It prompts us to investigate the impact of thalidomide on ECs and whether DF modulates changes in fibrinolysis induced by thalidomide. In this in vitro study, MM by itself alters the profibrinolytic potential of ECs decreasing the tissue plasminogen activator (t-PA) and increasing the plasminogen activator inhibitor 1 (PAI-1) levels which is potentiated by thalidomide. Defibrotide was able to counteract these effects. Additionally, DF upregulated the t-PA and downregulated PAI-1 gene expression modulated by thalidomide. Defibrotide also protects ECs from thalidomide-mediated cell death without interfering with its antitumor effects. These findings support DF clinical use for the prevention of DVT induced by immunomodulatory drugs.

Prophylaxis of venous thromboembolism: low molecular weight heparin compared to the selective anticoagulants rivaroxaban, dabigatran and fondaparinux

Newer therapeutic options available in the prevention of postoperative thromboembolism, currently focused on fondaparinux, rivaroxaban and dabigatran warrant an overall therapeutic assessment. The constitutive comparisons with enoxaparin are based on a combined outcome measure solely driven by the incidence of "asymptomatic deep vein thrombosis". Its validity as a clinically relevant endpoint is missing if antithrombotics of different classes are compared. This is because they target different phases of thrombogenesis i. e. ahead and beyond the asymptomatic stage of thrombosis. Additional concerns refer to the dosing-regimens and their practical administration: Fondaparinux, rivaroxaban and dabigatran are dosed to achieve maximum effects very close to their limits of tolerance whereas wide dosing spectra for the low molecular weight herparin (LMWH)'s indicate the potential for dose adaptation and increase. The other disadvantage to the control-heparin originates in the timing for the 1st administration which doesn't fit in with the "just-in-time" principle. So the enoxaparin-regimen is lacking in benchmark-quality - with the consequence that the meaning of the Phase III-trials does'nt go beyond a mere technical demarcation from the marketed variant of the product as defined by the stipulations in the package insert. As to tolerance the selective anticoagulants exhibit an increased risk of major and other clinically relevant bleeding, exceeding that of enoxaparin by 30% (P<0.001). The outcome of the meta-analyses on fondaparinux, rivaroxaban and dabigatran is supported by product-specific calculations and assessments of the European Medicine Equivalence Agency (EMEA). Rivaroxaban and dabigatran show significant age-dependent renal accumulation. Because the dose-finding studies were restricted to patients over 60 year old the regimens definitely established are not applicable to younger patients. The reason for the limited therapeutic index of the selective anticoagulants originates in their monovalent activity as such not adequately matching the complexity of thrombogenesis and early thrombus extension. Their class-specific limitations are compensated through more intensive dosage-regimens which result in accentuated bleeding complications. Connotatively the hypothesis emerged that antiXa- and IIa-effects interact synergistically which translates into enhanced efficacy and tolerance. Experimental studies on hirudin with pentasaccharide and hirudin with "lower low molecular weight heparin" (3KDA) support such rationale.