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Perfusion Sep 2020During extracorporeal membrane oxygenation, the large contact surface between the blood and the extracorporeal circuit causes a continuous activation of coagulation and... (Review)
Review
BACKGROUND
During extracorporeal membrane oxygenation, the large contact surface between the blood and the extracorporeal circuit causes a continuous activation of coagulation and inflammation. Unfractionated heparin, a glycosaminoglycan that must bind to antithrombin as a cofactor, is currently the standard anticoagulant adopted during extracorporeal membrane oxygenation. Antithrombin, beyond being a potent natural anticoagulant, acts in the cross-talk between coagulation and inflammatory system through anticoagulation and coagulation-independent effects.
OBJECTIVES
In this review, we describe, in the adult setting of veno-venous extracorporeal membrane oxygenation, the pathophysiological rationale for antithrombin use, the current practice of administration, and the effects of antithrombin on anticoagulation, bleeding, and outcomes.
DATA SOURCES
Studies on adults (18 years or older) on veno-venous extracorporeal membrane oxygenation published from 1995 to 2018 in order to evaluate the use of antithrombin.
RESULTS
In adults on veno-venous extracorporeal membrane oxygenation, antithrombin supplementation has a highly pathophysiological rationale since coagulation factor consumption, systemic inflammatory response syndrome, and endothelial activation are triggered by extracorporeal membrane oxygenation. Eleven articles are focused on the topic but among the authors there is no consensus on the threshold for supplementation (ranging from 70% to 80%) as well as on the dose (rarely standardized) and time of administration (bolus vs continuous infusion). Consistently, antithrombin is considered able to achieve better anticoagulation targets in or not in the presence of heparin resistance. The impact of antithrombin administration on bleeding still shows contrasting results.
CONCLUSION
Antithrombin use in veno-venous extracorporeal membrane oxygenation should be investigated on the threshold for supplementation, dose, and time of administration.
Topics: Anticoagulants; Antithrombins; Extracorporeal Membrane Oxygenation; Humans; Treatment Outcome
PubMed: 32228213
DOI: 10.1177/0267659120913803 -
Intensive Care Medicine Apr 2016Antithrombin III (AT III) is an anticoagulant with anti-inflammatory properties. We assessed the benefits and harms of AT III in critically ill patients. (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Antithrombin III (AT III) is an anticoagulant with anti-inflammatory properties. We assessed the benefits and harms of AT III in critically ill patients.
METHODS
We searched from inception to 27 August 2015 in CENTRAL, MEDLINE, EMBASE, CAB, BIOSIS and CINAHL. We included randomized controlled trials (RCTs) irrespective of publication status, date of publication, blinding status, outcomes published or language.
RESULTS
We included 30 RCTs with a total of 3933 participants. The majority of included trials were at high risk of bias. Combining all trials, regardless of bias, showed no statistically significant effect of AT III on mortality (RR 0.95, 95% CI 0.88-1.03, I (2) = 0%, fixed-effect model, 29 trials, 3882 participants). Among those with severe sepsis and disseminated intravascular coagulation (DIC), AT III showed no impact on mortality (RR 0.95, 95% Cl 0.88-1.03, I (2) = 0%, fixed-effect model, 12 trials, 2858 participants). We carried out multiple subgroup and sensitivity analyses to assess the benefits and harms of AT III and to examine the impact of risk of bias. AT III significantly increased bleeding events (RR 1.58, 95% CI 1.35-1.84, I (2) = 0%, fixed-effect model, 11 trials, 3019 participants). However, for all other outcome measures and analyses, the results did not reach statistical significance.
CONCLUSIONS
There is insufficient evidence to support AT III substitution in any category of critically ill participants including those with sepsis and DIC. AT III did not show an impact on mortality, but increased the risk of bleeding.
Topics: Antithrombin III; Antithrombins; Critical Illness; Disseminated Intravascular Coagulation; Humans; Randomized Controlled Trials as Topic; Sepsis
PubMed: 26862016
DOI: 10.1007/s00134-016-4225-7 -
Clinical Journal of the American... Feb 2023Nephrotic syndrome is associated with an acquired hypercoagulopathy that is thought to drive its predisposition for venous thromboembolism. Previous studies have... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Nephrotic syndrome is associated with an acquired hypercoagulopathy that is thought to drive its predisposition for venous thromboembolism. Previous studies have suggested that urinary antithrombin (AT) loss leading to acquired AT deficiency is the primary mechanism underlying this hypercoagulopathy, but this hypothesis has not been directly tested. The objectives of this study were to test the influence of AT levels on hypercoagulopathy in nephrotic syndrome patient samples and perform meta-analyses to evaluate the likelihood of AT deficiency in patients with nephrotic syndrome.
METHODS
Samples from three independent nephrotic syndrome cohorts were analyzed. AT antigen and activity assays were performed using ELISA and amidolytic assays, respectively. Plasma thrombin generation, albumin, and urine protein-to-creatinine ratios were determined using established methods. Meta-analyses were performed by combining these new data with previously published data.
RESULTS
AT levels were not consistently related to either plasma albumin or proteinuria. AT was quantitatively related to hypercoagulopathy in adult nephrotic syndrome, whereas AT activity was inconsistently associated with hypercoagulopathy in childhood nephrotic syndrome. Notably, hypercoagulopathy did not differ between patients with normal AT levels and those with levels below the threshold used to define clinical AT deficiency (<70%). Moreover, ex vivo AT supplementation did not significantly alter hypercoagulopathy in AT-deficient plasma samples. The meta-analyses demonstrated that AT deficiency was not a uniform feature of nephrotic syndrome and was more common in children than adults.
CONCLUSIONS
These data suggest that AT deficiency plays only a limited role in the mechanisms underlying the acquired hypercoagulopathy of nephrotic syndrome. Moreover, AT deficiency was not present in all patients with nephrotic syndrome and was more likely in children than adults despite the higher risk for venous thromboembolism in adults than children.
Topics: Adult; Child; Humans; Nephrotic Syndrome; Antithrombins; Venous Thromboembolism; Cohort Studies; Antithrombin III
PubMed: 36754010
DOI: 10.2215/CJN.0000000000000047 -
Clinical and Applied... 2020In Japan, the dose of the new recombinant antithrombin III concentrate (rAT-gamma) is titrated according to patient body weight (BW), while conventional plasma-derived... (Comparative Study)
Comparative Study Observational Study
Comparison of Protective Effects of Recombinant Antithrombin Gamma and Plasma-Derived Antithrombin on Sepsis-Induced Disseminated Intravascular Coagulation and Multiple Organ Failure.
In Japan, the dose of the new recombinant antithrombin III concentrate (rAT-gamma) is titrated according to patient body weight (BW), while conventional plasma-derived antithrombin concentrates (AT) are administered as a fixed dose. Therefore, it is anticipated that rAT-gamma could produce better treatment effects than AT. The aim of this study was to compare the organ protective effects of doses of rAT-gamma and AT administered in clinical practice for septic disseminated intravascular coagulation (DIC) and multiple organ failure. This study was performed at a single university hospital in Japan. A total of 49 patients with antithrombin deficiency secondary to septic DIC who were administered either rAT-gamma (n = 26) or AT (n = 23) were retrospectively analyzed to assess the dose of supplemental antithrombin concentrates, plasma antithrombin activity, Japanese Association for Acute Medicine (JAAM)-DIC score, and modified Sequential Organ Failure Assessment (SOFA) score on days 0, 3 and 6. The AT-equivalent dose per kg BW of rAT-gamma (equal to the initial rAT-gamma dose per kg BW divided by 1.2) was significantly higher than the dose per kg BW of AT (AT 23.4 ± 5.1 vs. rAT 28.9 ± 3.9 IU/kg/day; P < 0.001). Consequently, serial increases in plasma antithrombin levels occurred more rapidly in the rAT-gamma group (P = 0.036). JAAM DIC and modified SOFA scores revealed significantly greater improvement in the rAT versus the AT group (JAAM DIC score: P = 0.042, mSOFA score: P = 0.005). The results of this study suggest that AT supplementation adjusted for patient BW might further improve septic DIC and multiple organ failure.
Topics: Aged; Antithrombin Proteins; Antithrombins; Disseminated Intravascular Coagulation; Female; Humans; Male; Middle Aged; Recombinant Proteins; Retrospective Studies; Sepsis
PubMed: 33332196
DOI: 10.1177/1076029620981630 -
Biomolecules Apr 2021Antithrombin (AT) is a serine protease inhibitor, its activity is highly accelerated by heparin. Mutations at the heparin-binding region lead to functional defect, type...
Antithrombin (AT) is a serine protease inhibitor, its activity is highly accelerated by heparin. Mutations at the heparin-binding region lead to functional defect, type II heparin-binding site (IIHBS) AT deficiency. The aim of this study was to investigate and compare the molecular background of AT Budapest 3 (p.Leu131Phe, ATBp3), AT Basel (p.Pro73Leu), and AT Padua (p.Arg79His) mutations. Advanced in silico methods and heparin-binding studies of recombinant AT proteins using surface plasmon resonance method were used. Crossed immunoelectrophoresis and Differential Scanning Fluorimetry (NanoDSF) were performed in plasma samples. Heparin affinity of AT Padua was the lowest (KD = 1.08 × 10 M) and had the most severe consequences affecting the allosteric pathways of activation, moreover significant destabilizing effects on AT were also observed. KD values for AT Basel, ATBp3 and wild-type AT were 7.64 × 10 M, 2.15 × 10 M and 6.4 × 10 M, respectively. Heparin-binding of AT Basel was slower, however once the complex was formed the mutation had only minor effect on the secondary and tertiary structures. Allosteric activation of ATBp3 was altered, moreover decreased thermostability in ATBp3 homozygous plasma and increased fluctuations in multiple regions of ATBp3 were observed by in silico methods suggesting the presence of a quantitative component in the pathogenicity of this mutation due to molecular instability.
Topics: Antithrombin III; Binding Sites; Female; Heparin; Humans; Immunoelectrophoresis; Kinetics; Male; Molecular Dynamics Simulation; Polymorphism, Single Nucleotide; Protein Binding; Recombinant Proteins; Surface Plasmon Resonance
PubMed: 33917853
DOI: 10.3390/biom11040544 -
Journal of Clinical Laboratory Analysis Nov 2022Inherited AT deficiency is an autosomal-dominant thrombophilic disorder usually caused by various SERPINC1 defects associated with a high risk of recurrent venous...
BACKGROUND
Inherited AT deficiency is an autosomal-dominant thrombophilic disorder usually caused by various SERPINC1 defects associated with a high risk of recurrent venous thromboembolism. In this article, the phenotype, gene mutation, and molecular pathogenic mechanisms were determined in three pedigrees with inherited AT deficiency.
METHODS
Coagulation indices were examined on STAGO STA-R-MAX analyzer. The AT:Ag was analyzed by ELISA. All exons and flanking sequences of SERPINC1 were amplified by PCR. AT wild type and three mutant expression plasmids were constructed and then transfected into HEK293FT cells. The expression level of AT protein was analyzed by ELISA and Western blot.
RESULTS
The AT:A and AT:Ag of probands 1 and 3 were decreased to 49% and 52 mg/dL, 38% and 44 mg/dL, respectively. The AT:A of proband 2 was decreased to 32%. The SERPINC1 gene analysis indicated that there was a p.Ile421Thr in proband 1, a p.Leu417Gln in proband 2, and a p.Met252Thr in proband 3, respectively. The AT mRNA expression level of the three mutants was not significantly different from AT-WT by qRT-PCR. The results of ELISA and Western blot tests showed that the AT-M252T and AT-I421T mutants had a higher AT expression than the AT wild type (AT-WT), and the AT protein expression of AT-L417Q mutants had no significant difference compared with AT-WT in the cell lysate. The AT expression levels of AT-M252T and AT-I421T mutants were lower than that of AT-WT, and there was no significant difference between AT-L417Q mutant and AT-WT in the supernatant.
CONCLUSION
The p.I421T and p.M252T mutations affected the secretion of AT protein leading to type I AT deficiency of probands 1 and 3. The p.Leu417Gln mutation was responsible for the impaired or ineffective activity AT protein in proband 2 and caused type II AT deficiency.
Topics: Humans; Pedigree; Antithrombin III Deficiency; Phenotype; Mutation; Antithrombins
PubMed: 36268972
DOI: 10.1002/jcla.24732 -
Artificial Organs Dec 2023Bleeding and thrombosis are common extracorporeal membrane oxygenation (ECMO) complications associated with increased mortality. Heparin is the most commonly used ECMO...
BACKGROUND
Bleeding and thrombosis are common extracorporeal membrane oxygenation (ECMO) complications associated with increased mortality. Heparin is the most commonly used ECMO anticoagulant, employed in 94% of cases. Reduced antithrombin III (AT3) levels could decrease heparin effectiveness. Neonates have inherently lower levels of AT3 than adults, and pediatric patients on ECMO can develop AT3 deficiency. One potential approach for patients on ECMO with AT3 deficiency is exogenous AT3 supplementation. However, there is conflicting data concerning the use of AT3 for pediatric and neonatal patients on ECMO.
METHODS
We analyzed the Bleeding and Thrombosis during ECMO database of 514 neonatal and pediatric patients on ECMO. We constructed daily regression models to determine the association between AT3 supplementation and rates of bleeding and thrombosis. Given the physiological differences between pediatric patients and neonates, we constructed separate models for each.
RESULTS
AT3 administration was associated with increased rates of daily bleeding among pediatric (adjusted odds ratio [aOR] 1.59, p < 0.01) and neonatal (aOR 1.37, p = 0.04) patients. AT3 supplementation did not reduce the rate of thrombosis for either pediatric or neonatal patients.
CONCLUSION
AT3 administration was associated with increased rates of daily bleeding, a hypothesized potential complication of AT3 supplementation. In addition, AT3 supplementation did not result in lower rates of thrombosis. We recommend clinicians utilize caution when considering supplementing patients on ECMO with exogenous AT3.
Topics: Infant, Newborn; Adult; Humans; Child; Antithrombin III; Extracorporeal Membrane Oxygenation; Retrospective Studies; Anticoagulants; Heparin; Thrombosis; Hemorrhage; Dietary Supplements
PubMed: 37658611
DOI: 10.1111/aor.14639 -
Journal of Pharmaceutical Sciences May 2018Low-molecular-weight heparins (LMWHs) are widely used as clinical anticoagulant drugs. LMWHs are heterogeneous and highly negatively charged glycans prepared by chemical...
Low-molecular-weight heparins (LMWHs) are widely used as clinical anticoagulant drugs. LMWHs are heterogeneous and highly negatively charged glycans prepared by chemical or enzymatic depolymerization of unfractionated heparin. The detailed structural analysis of a LMWH is essential for the drug quality control. In this study, an LMWH, enoxaparin sodium (a generic version of Lovenox) was separated into different molecular weight fractions by a Superdex peptide column. The disaccharide compositions, 3-O-sulfo group-containing tetrasaccharides composition, and antithrombin III-binding affinity of the fractions from this LMWH were analyzed. The results showed that all the fractions had very similar disaccharide and 3-O-sulfo group-containing tetrasaccharide compositions, but the fraction containing larger-sized chains had higher antithrombin III-binding affinity.
Topics: Anticoagulants; Antithrombin III; Binding Sites; Disaccharides; Enoxaparin; Heparin, Low-Molecular-Weight; Humans; Molecular Weight; Oligosaccharides
PubMed: 29339133
DOI: 10.1016/j.xphs.2018.01.008 -
Effect of prothrombin Belgrade mutation, causing antithrombin resistance, on fibrin clot properties.International Journal of Laboratory... Apr 2024Prothrombin Belgrade mutation is the result of the c.1787G>A substitution in the prothrombin gene. It is located in the antithrombin and sodium binding site and leads to...
INTRODUCTION
Prothrombin Belgrade mutation is the result of the c.1787G>A substitution in the prothrombin gene. It is located in the antithrombin and sodium binding site and leads to impaired inactivation of thrombin by antithrombin, resulting in antithrombin resistance and thrombotic disorders. However, it negatively affects sodium binding and may have hypocoagulant effects. Considering that prothrombin Belgrade mutation mechanism is still not fully elucidated and that sodium binding is important for thrombin affinity towards fibrinogen, our aim was to determine whether this mutation affects fibrin clot formation and lysis.
METHODS
Using HEK293T cell line, recombinant wild type and mutated prothrombin were generated by transient transfection. Samples that correspond to plasma of a non-carrier, heterozygous and homozygous carriers were reconstituted using prothrombin deficient plasma and recombinant proteins. Reconstituted samples were used in OHP assay (Overall Hemostasis Potential) to determine kinetic profiles of coagulation and fibrinolysis. Clot turbidity assay was performed to observe kinetics of clot formation and lysis more closely. Fibrin clots formed in reconstituted plasma samples were analyzed by confocal microscopy to determine density of fibrin network. Fibrin clots were additionally observed using electron microscopy to determine thickness of individual fibrin fibers.
RESULTS
No significant difference found in OHP, OCP, OFP, and fibrin network density between wild type, heterozygous, and homozygous carrier reconstituted plasma samples. There were significant differences between samples for slope and slope time parameters in kinetic profiles and fibrin fiber thickness.
CONCLUSIONS
Results indicate that prothrombin Belgrade mutation has no significant impact on fibrinolysis, however it may affect kinetics of clot formation and its architecture.
Topics: Humans; Fibrin; Prothrombin; Antithrombins; Thrombin; HEK293 Cells; Thrombosis; Fibrinolysis; Anticoagulants; Antithrombin III; Mutation; Sodium
PubMed: 37918971
DOI: 10.1111/ijlh.14195 -
International Journal of Laboratory... Jun 2022Antithrombin (AT), protein C (PC), and protein S (PS) are natural anticoagulant proteins that deficiency in each of them is associated with an increased risk of venous...
BACKGROUND
Antithrombin (AT), protein C (PC), and protein S (PS) are natural anticoagulant proteins that deficiency in each of them is associated with an increased risk of venous thromboembolism.The overlapping of plasma levels of AT, PC, and PS between healthy individuals and heterozygote carriers poses significant challenges in precise diagnosis. This study aimed to evaluate the effect of most influencing variables on plasma levels of these proteins and propose specific reference intervals to improve the interpretation of the laboratory results.
METHODS
This study was conducted on 1464 individuals who were referred to Massoud medical laboratory, Tehran, Iran, from 2019 to 2020. AT and PC were measured through chromogenic assay and PS plasma level with the clot-based assay. A multivariable linear regression model was performed to evaluate the effect of sex, age, oral contraceptive (OCP) intake, and menopause state. Normal deviate z value was used for different subgroups to justify the need for a separate reference interval.
RESULTS
1200 verified healthy individuals (434 males and 766 females), aged between 18 and 69 years were included in the study. The mean ± SD age of the participants was 39.78 ± 11.79 years. The age-related effects for AT were found in men. In females, increasing age was associated with a rise in AT, PC, and PS plasma levels. No sex difference was found in AT plasma level. OCP-taking is associated with a decrease in AT and an increase in PC plasma levels.
CONCLUSION
This is the largest study ever conducted on healthy individuals in the Iranian population, using specific reference interval results in accurate diagnosis of true AT, PC, and PS deficiency.
Topics: Adolescent; Adult; Aged; Anticoagulants; Antithrombin III; Antithrombins; Contraceptives, Oral; Female; Humans; Iran; Male; Menopause; Middle Aged; Protein C; Protein C Deficiency; Protein S; Protein S Deficiency; Young Adult
PubMed: 35112486
DOI: 10.1111/ijlh.13804