Patients with Coronary Artery Disease Have an Increased Incidence of Aspirin Resistance: Association of PFA-100 Closure Time with Clinical Findings.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1859-1859 ◽  
Author(s):  
Andrew L. Frelinger ◽  
Matthew D. Linden ◽  
Mark I. Furman ◽  
Marsha L. Fox ◽  
Marc R. Barnard ◽  
...  
Keyword(s):  
Platelet Function ◽  
Aspirin Resistance ◽  
Clinical Findings ◽  
Prior History ◽  
Limited Data ◽  
Closure Time ◽  
Cyclooxygenase 1 ◽  
History Of ◽  
Artery Disease

Abstract Background: The occurrence of thrombotic events despite aspirin (ASA) therapy in patients with vascular disease has been termed ASA resistance. However, limited data are available correlating laboratory evidence of platelet function with clinical ASA resistance. The PFA-100 collagen/epinephrine (COL/EPI) cartridge can detect the ASA-induced inhibition of platelet cyclooxygenase 1 in a high shear flow environment that mimics in vivo arterial conditions. Aim: To investigate whether there is an association of PFA-100 test results with clinical ASA resistance. Methods: Peripheral blood was collected prior to angiography from 560 sequential ASA-treated patients (81 or 325 mg > 3 d). Patients receiving thienopyridines were not excluded but those receiving GPIIb-IIIa antagonists were. Patients with normal angiographic arteries ("No CAD", low probability of ASA resistance) were compared to those with angiographic CAD or a single prior CAD event and to those with multiple CAD events ("CAD" and "Repeat CAD" respectively, higher probability of ASA resistance). Citrate 3.8% anticoagulated blood was tested in the PFA-100 in duplicate using the COL/EPI test cartridge. Patients in the No CAD group were younger, more often female, and less often diabetic, hypertensive, and lipidemic than CAD or Repeat CAD patients. Results: A short (< 142 s) closure time (CT) in at least one of the duplicate PFA-100 COL/EPI cartridges occurred more frequently in CAD and Repeat CAD patients compared to No CAD patients (p < 0.05, Table). Conclusions: Failure of ASA to inhibit platelet function, as measured by the PFA-100, is associated with CAD, even in patients without prior history of CAD. The PFA-100, a shear-dependent system, may therefore be a useful test to assess the presence of ASA resistance. This test, unlike some tests for aspirin resistance, does not include ADP and therefore can be used in patients receiving thienopyridines (a frequent co-medication with aspirin). No CAD CAD Repeat CAD *p<0.05 vs. No CAD PFA-100 CT < 142 s (no. of patients) 4 45 26 PFA-100 CD ≥ 142 s (no. of patients) 79 251 155 Total (no. of patients) 83 296 181 % PFA-100 CT < 142 s 5% 15%* 14%*

Severe Hemolytic Reaction Due to Anti-JK3

1999 ◽  
Vol 123 (10) ◽  
pp. 949-951
Author(s):  
Carol S. Marshall ◽  
Denis Dwyre ◽  
Robin Eckert ◽  
Liisa Russell
Keyword(s):  
The United States ◽  
Cell Phenotype ◽  
Prior History ◽  
Ethnic Variability ◽  
Hemolytic Transfusion Reaction ◽  
History Of ◽  
Rare Phenotype ◽  
Antibody Screen

Abstract A 35-year-old gravida 3, para 3 Filipino woman with a negative antibody screen, no prior history of transfusion, and no hemolytic disease of the newborn in her children suffered a massive postpartum hemorrhage requiring transfusion. A severe hemolytic transfusion reaction occurred 5 days after delivery. Subsequently, a panagglutinin on a routine antibody identification panel was identified as anti-Jk3. The patient's red blood cell phenotype was Jk(a−b−) and all of her children were Jk(a−b+), yet the antibody that formed reacted with equal strength against all Jka- or Jkb-positive cells. The rare Jk(a−b−) phenotype is more common in Polynesians. Anti-Jk3, like other Kidd system antibodies, is difficult to detect because in vivo production may be absent between provocative episodes and because these antibodies often show weak in vitro reactions. The increasing numbers of Pacific Islanders in the United States could result in more frequent encounters with this rare phenotype. Increased awareness of ethnic variability in blood phenotypes and of the capricious nature of Kidd antibodies can help pathologists and technologists deal more effectively with these cases.

The influence of the haematocrit on primary haemostasis in vitro

2005 ◽  
Vol 94 (12) ◽  
pp. 1213-1218 ◽  
Author(s):  
Marco Eugster ◽  
Walter H. Reinhart
Keyword(s):  
Platelet Function ◽  
Type I Collagen ◽  
Inverse Correlation ◽  
Type I ◽  
Membrane Pore ◽  
Closure Time ◽  
Function Analyzer ◽  
Platelet Function Analyzer

SummaryPrimary haemostasis consists of platelet adhesion to subendothelial collagen, their activation and aggregation and finally the formation of a platelet plug. Erythrocytes are involved in this process because they flow in the center of the vessel and push platelets towards the site of action on the vessel wall and enhance shear forces, which activate platelets. In the platelet function analyzer PFA-100® (Dade Behring, Düdingen, Switzerland), the in vivo situation is simulated in vitro with blood being aspirated at high shear rates (5000s-1) through a capillary into a membrane pore with a diameter of 150 μm coated with type I collagen and either epinephrine or adenosine diphosphate. Aggregating platelets plug the pore and stop the flow, which is measured as the closure time. We analysed the influence of erythrocytes on platelet function analyzer measurements by systematic variation of the haematocrit (20,30,40,and 50%) at constant platelet counts of 289±61 ×103/μl plasma, or 152±30 ×103/μl blood, 96±9 ×103/μl blood and 54±5 ×103/μl blood, respectively. An inverse correlation was found between haematocrit and closure time under all circumstances. A decrease of the platelet count by 50 ×103 /μl could be compensated for by a 10% increase in haematocrit. The haematocrit must, therefore, be taken into consideration for the correct interpretation of PFA-100® measurements. Our data also provide a pathophysiological rationale to reduce the risk of bleeding in patients with thrombocytopenia and anaemia by normalizing the haematocrit with erythrocyte transfusions.

scholarly journals Extensive Cerebral Venous Thrombosis Secondary to Recreational Nitrous Oxide Abuse

2021 ◽  
pp. 1-4
Author(s):  
Wassim Farhat ◽  
Aaron Pariente ◽  
Rami Mijahed
Keyword(s):  
Nitrous Oxide ◽  
Venous Thrombosis ◽  
Vitamin B12 ◽  
Cerebral Venous Thrombosis ◽  
Medical Literature ◽  
Homocysteine Level ◽  
Prior History ◽  
Limited Data ◽  
Folate Supplementation ◽  
History Of

Nitrous oxide, colloquially known as “whippets,” is a commonly abused inhalant by adolescents and young adults. There are limited data describing the adverse effects of this abuse. We present a 16-year-old girl with no medical history who presented to the emergency department for confusion, hallucinations, weakness, and headaches. Imaging revealed extensive cerebral thrombosis. She had no prior history of venous or arterial thrombosis. Hypercoagulability workup demonstrated an elevated homocysteine level. She was treated with effective anticoagulation and vitamin B12 folate supplementation. To our knowledge, there are a very few cases in the medical literature of cerebral venous thrombosis following the use of nitrous oxide. The pathophysiology of the disorder appears to be linked to the metabolism of vitamin B12 inducing hyperhomocysteinemia and a procoagulant state.

scholarly journals SARS-COV-2 infection in a patient with Evans syndrome: A silent enemy or an ally?

2020 ◽  
pp. 115-115
Author(s):  
Nikola Pantic ◽  
Mirjana Mitrovic ◽  
Marijana Virijevic ◽  
Nikica Sabljic ◽  
Zlatko Pravdic ◽  
...  
Keyword(s):  
Platelet Count ◽  
Case Report ◽  
Autoimmune Diseases ◽  
Reference Range ◽  
Prior History ◽  
Limited Data ◽  
Evans Syndrome ◽  
History Of ◽  
Current Outbreak ◽  
Platelet Count Monitoring

During the current outbreak of Coronavirus disease 2019 (COVID-19), the way to manage patients with autoimmune diseases remains elusive due to limited data available. Case report: Addressing this issue we report a case of a COVID-19 positive 20-year-old female with prior history of Evans syndrome. She remained asymptomatic even though she had been treated with immunosuppressants (prednisolone and azathioprine) together with romiplostim. Moreover, her course of infection was accompanied by thrombocytosis, although her platelet count was mostly below the reference range before the infection. The patient was monitored vigilantly, with special regard to platelet count and signs of thrombotic events. Conclusion: Platelet count monitoring and romiplostim administration should be performed more cautiously in ITP patients infected by SARS-CoV-2.

Cardiac and cerebral manifestations of the antiphospholipid syndrome

2001 ◽  
Vol 21 (02) ◽  
pp. 60-65
Author(s):  
F. Jung ◽  
I. Scharrer
Keyword(s):  
Aortic Valve ◽  
Antiphospholipid Syndrome ◽  
The Other ◽  
Prior History ◽  
Review Of The Literature ◽  
Left Main ◽  
Vessel Occlusion ◽  
History Of ◽  
Artery Disease ◽  
Valvular Lesions

Summary Aim: To describe cardiac and cerebral manifestations in eight patients with the antiphospholipid syndrome and a review of the literature. Patients and Methods: We studied eight patients with the antiphospholipid syndrome (APS) with either cardiac or cerebral or both manifestations. All patients fulfilled the proposed classification criteria for the APS according to the SSC of the ISTH. One patient died and had an autopsy. Results: Five of the eight patients had coronary artery disease with either thrombotic coronary occlusions or high grade stenosis, of which three patients had an occlusion of the left main artery or LAD. As valvular lesions have been described in association with the APS it is to note that three patients had thickening either of the mitral valve or aortic valve and one patient had an aortic valve replacement. The other two patients presented with a history of cerebral infarction. One of these patients also had a prior history of myocardial infarction, whereas the other patient had a history of aortic valve endocarditis. Conclusion: The APS can be associated with cardiac and cerebral manifestations. Acute thrombotic vessel occlusion presents as one of the most frequent vascular manifestations. Also valvular lesions can be associated with the APS.

scholarly journals The risk and prevention of venous thromboembolism in the pregnant traveller

2019 ◽  
Vol 27 (2) ◽  
Author(s):  
Divya J Karsanji ◽  
Shannon M Bates ◽  
Leslie Skeith
Keyword(s):  
Risk Factors ◽  
Venous Thromboembolism ◽  
Absolute Risk ◽  
Careful Consideration ◽  
Prior History ◽  
Average Risk ◽  
Limited Data ◽  
Compression Stockings ◽  
History Of ◽  
The Absolute

Abstract Background The average risk of venous thromboembolism (VTE) in long haul travellers is approximately 2.8 per 1000 travellers, which is increased in the presence of other VTE risk factors. In pregnant long-haul travellers, little is known in terms of the absolute risk of VTE in these women and, therefore, there is limited consensus on appropriate thromboprophylaxis in this setting. Objective This review will provide guidance to allow practitioners to safely minimize the risk of travel-related VTE in pregnant women. The suggestions provided are based on limited data, extrapolated risk estimates of VTE in pregnant travellers and recommendations from published guidelines. Results We found that the absolute VTE risk per flight appears to be &lt;1% for the average pregnant or postpartum traveller. In pregnant travellers with a prior history of VTE, a potent thrombophilia or strong antepartum risk factors (e.g. combination of obesity and immobility), the risk of VTE with travel appears to be &gt;1%. Postpartum, the risk of VTE with travel may be &gt;1% for women with thrombophilias (particularly in those with a family history) and other transient risk factors and in women with a prior VTE. Conclusions Based on our findings, we recommend simple measures be taken by all pregnant travellers, such as frequent ambulation, hydration and calf exercises. In those at an intermediate risk, we suggest a consideration of 20–30 mmHg compression stockings. In the highest risk group, we suggest careful consideration for low-molecular-weight heparin thromboprophylaxis. If there are specific concerns, we advise consultation with a thrombosis expert at the nearest local centre.

Isoprostane (8-Epiprostaglandin F2α) Plasma Concentration and Aspirin Resistance in Patients after Ischaemic Stroke.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 930-930
Author(s):  
Krystyna M. Zawilska ◽  
Marcin M. Zytkiewicz ◽  
Ewelina E. Hanszke ◽  
Zofia Z. Turowiecka ◽  
Liwia L. Gielwanowska ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Ischaemic Stroke ◽  
Platelet Function ◽  
Prostaglandin F2α ◽  
Thromboxane A2 ◽  
Aspirin Resistance ◽  
Thromboxane B2 ◽  
Control Group ◽  
Platelet Function Tests ◽  
Closure Time

Abstract Background The limited efficacy of secondary prevention for ischaemic stroke may be partially related to aspirin resistance leading to continuous generation of intraplatelet thromboxane A2. Besides other underlying metabolic mechanisms, an oxidant stress along with nonenzymatic biosynthesis of isoprostanes supporting the platelet activation has been suggested. Aims We analyzed the incidence of aspirin resistance in survivors of ischaemic stroke and compared the usefulness of some platelet tests designed for its laboratory exploration. Also we searched for relationship between isoprostane concentration and results of platelet function tests. Material and Methods Forty four patients, at least a month after acute onset of ischaemic stroke were included into the study. All of them have been receiving 75–150 mg aspirin daily at least for a month. The control group for 11-dehydro Thromboxane B2 measurements consisted of 12 healthy volunteers. The platelet function was investigated by platelet aggregation tests induced by either ADP (3.5 and 5.0 μM), collagen (2 μg/ml) or arachidonic acid (AA) (0.6 mM) and by measurement of closure time in PFA-100 analyzer. Thromboxane A2 metabolite - 11-dehydro Thromboxane B2 (11-dTxB2) and isoprostane - 8-epi Prostaglandin F2α (8-epiPgF2α) plasma concentration by immunoenzymatic method (EIA Kits from Cayman Chemicals) were also determined. The aspirin ingestion was controlled by diminished intraplatelet concentration of malonyldialdehyde. Aspirin resistance has been determined by the following criteria: the intensity of platelet aggregation induced by ADP >60%, collagen >70%, AA >20%, PFA-100 closure time <165 s and 11-dTxB2 concentration >mean of the control group minus SD. Results Table 1 Statistically significant inverse correlations have been found between the plasma concentration of 11-dTxB2 and PFA-100 (Col/Epi) closure time (r= −0.31; p= 0.039) as well as between plasma concentration of 8-epiPgF2α and PFA-100 (Col/Epi) closure time (r= −0.36; p= 0.019). Summary/conclusions Laboratory platelet function tests reveal aspirin resistance in almost half of patients after ischaemic stroke. The most significant correlation has been found between plasma concentration of 11-dehydro Thromboxane B2 and PFA-100 closure time. An important interrelationship observed between PFA-100 closure time and plasma concentration of 8-epi Prostaglandin F2α may support the hypothesis of nonenzymatic production of isoprostanoids with platelet proaggregatory activity, playing a role in aspirin resistance. The frequency of aspirin resistance in patients after ischaemic stroke ADP 3.5μM ADP 5.0μM Collagen Arachidonic acid PFA-100 11-dTxB2 45% 52% 20% 7% 52% 43%

scholarly journals Comparing the performance of QuantiFERON-TB Gold Plus with QuantiFERON-TB Gold in-tube among highly TB exposed gold miners in South Africa

2021 ◽  
Vol 5 ◽  
pp. 66
Author(s):  
Thobani Ntshiqa ◽  
Violet Chihota ◽  
Raoul Mansukhani ◽  
Lindiwe Nhlangulela ◽  
Kavindhran Velen ◽  
...  
Keyword(s):  
South Africa ◽  
Latent Tuberculosis ◽  
Prior History ◽  
Interferon Gamma Release Assay ◽  
Limited Data ◽  
History Of ◽  
Gold Miners ◽  
Release Assay ◽  
Additional Antigen ◽  
Hiv Negative

Background: QuantiFERON-TB Gold in-tube (QFT-GIT) is an interferon-gamma release assay (IGRA) used to diagnose latent tuberculosis infection. Limited data exists on performance of QuantiFERON-TB Gold-Plus (QFT-Plus), a next generation of IGRA that includes an additional antigen tube 2 (TB2) while excluding TB7.7 from antigen tube 1 (TB1), to measure TB specific CD4+ and CD8+ T lymphocytes responses. We compared the performance of QFT-Plus with QFT-GIT among highly TB exposed goldminers in South Africa. Methods: We enrolled HIV-negative goldminers in South Africa, ≥33 years with no prior history of TB disease or evidence of silicosis. Blood samples were collected for QFT-GIT and QFT-Plus. QFT-GIT was considered positive if TB1 tested positive; while QFT-Plus was positive if both or either TB1 or TB2 tested positive, as per manufacturer's recommendations. We compared the performance of QFT-Plus with QFT-GIT using Cohen’s Kappa. To assess the specific contribution of CD8+ T-cells, we used TB2−TB1 differential values as an indirect estimate. A cut-off value was set at 0.6. Logistic regression was used to identify factors associated with having TB2-TB1>0.6 difference on QFT-Plus. Results: Of 349 enrolled participants, 304 had QFT-Plus and QFT-GIT results: 205 (68%) were positive on both assays; 83 (27%) were negative on both assays while 16 (5%) had discordant results. Overall, there was 94.7% (288/304) agreement between QFT-Plus and QFT-GIT (Kappa = 0.87). 214 had positive QFT-Plus result, of whom 202 [94.4%, median interquartile range (IQR): 3.06 (1.31, 7.00)] were positive on TB1 and 205 [95.8%, median (IQR): 3.25 (1.53, 8.02)] were positive on TB2. A TB2-TB1>0.6 difference was observed in 16.4% (35/214), with some evidence of a difference by BMI; 14.9% (7/47), 9.8% (9/92) and 25.3% (19/75) for BMI of 18.5-24.9, 18.5-25 and >30 kg/m2, respectively (P=0.03). Conclusion: In a population of HIV-negative goldminers, QFT-Plus showed a similar performance to QFT-GIT.

Sign in / Sign up

Export Citation Format

Share Document