Acute Acquired Immune Thrombocytopenia After Cardiac Surgery: A Challenging Case

Thrombocytopenia is a common condition that recognizes an infinite number of possible causes, especially in specific settings like the one covered in this case report: the postoperative period of cardiac surgery. We report a case of an old male with multiple comorbidities who underwent a coronary angioplasty procedure and aortic valve replacement. He showed severe thrombocytopenia in the postoperative days. Differential diagnosis required a big effort, also for the experts in the field. Our goal was to aggressively treat the patient with prednisolone, platelets, and intravenous immunoglobulins to maximize the prognosis. Our patient developed no complications and was discharged successfully

Platelet Aggregation Pattern on Light Transmission Aggregometry Among Malaysian Healthy Individuals

@#Introduction: Platelet aggregation test using light transmission aggregometry (LTA) is considered as the gold standard for evaluation of platelet function. Variations of platelet aggregation had been reported in apparently healthy individuals whereby a normal cut–off value established locally is highly recommended. This study aims to determine the platelet aggregation pattern and the preliminary findings on reference values for multiple agonists–induced platelet aggregation among Malaysian healthy individuals in a single centre. Method: A total number of 63 informed consented healthy individuals consisted of Malay, Chinese and Indian were recruited among staff and blood donors at National Blood Centre, Kuala Lumpur. Platelet aggregation was measured using LTA against adenosine diphosphate 10 µM (ADP10), collagen 0.19 mg/mL (COL), ristocetin 1.5 mg/mL (RIS), arachidonic acid 1 mM (AA) and epinephrine 10 µM (EPI). Results were expressed as percent final aggregation (%FA). Reference values were calculated from mean±2SD. Results: Age, gender and ethnic groups had no significant effect on platelet aggregation. A variability of platelet aggregation response to EPI was observed among the healthy individuals. Ten of 33 respondents (30%) had impaired aggregation with <20% FA in response to EPI. The local population showed a slightly higher aggregation pattern in response to COL, RIS, AA and EPI (excluding non-responders) compared to manufacturer’s reference values. Conclusion: This study has provided a glimpse of the aggregation pattern of the local nationality showing considerable differences in the reference values from manufacturer’s; thus highlighting the need of establishing local reference values.

Clinical outcomes and predictive model of platelet reactivity to clopidogrel after acute ischemic vascular events / 中华医学杂志(英文版)

Background:@#High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease. We explored a predictive model of platelet reactivity to clopidogrel and the relationship with clinical outcomes.@*Methods:@#A total of 441 patients were included. Platelet reactivity was measured by light transmittance aggregometry after receiving dual antiplatelet therapy. HTPR was defined by the consensus cutoff of maximal platelet aggregation >46% by light transmittance aggregometry. CYP2C19 loss-of-function polymorphisms were identified by DNA microarray analysis. The data were compared by binary logistic regression to find the risk factors. The primary endpoint was major adverse clinical events (MACEs), and patients were followed for a median time of 29 months. Survival curves were constructed with Kaplan-Meier estimates and compared by logrank tests between the patients with HTPR and non-HTPR.@*Results:@#The rate of HTPR was 17.2%. Logistic regression identified the following predictors of HTPR: age, therapy regimen, body mass index, diabetes history, CYP2C19*2, or CYP2C19*3 variant. The area under the curve of receiver operating characteristic for the HTPR predictive model was 0.793 (95% confidence interval: 0.738–0.848). Kaplan-Meier analysis showed that patients with HTPR had a higher incidence of MACE than those with non-HTPR (21.1% vs. 9.9%; χ2 = 7.572, P = 0.010).@*Conclusions:@#Our results suggest that advanced age, higher body mass index, treatment with regular dual antiplatelet therapy, diabetes, and CYP2C19*2 or CYP2C19*3 carriers are significantly associated with HTPR to clopidogrel. The predictive model of HTPR has useful discrimination and good calibration and may predict long-term MACE.

Effect of aspirin on anti-platelet aggregation function in children with Kawasaki disease / 中国实用儿科杂志

OBJECTIVE: To evaluate the anti-platelet aggregation function of aspirin in children with Kawasaki disease(KD).METHODS: The clinical data of KD patients who was admitted to Capital Institute of Pediatrics-Peking University Teaching Hospital from September 2016 to September 2018 was retrospectively analyzed. All the children were treated with aspirin routinely:high-dose(30-50)mg/（kg·d)in acute stage and low-dose aspirin(3-5)mg/（kg·d)in the recovery period. Then the light transmission aggregometry(LTA)was used to determine the platelet aggregation rate of different doses of aspirin in order to evaluate the anti-platelet aggregation function,and the risk factors of aspirin resistance(AR)were analyzed by statistical method. RESULTS:(1)The platelet aggregation rate(AA%)after treatment with high-dose and low-dose aspirin in children with KD was 30.3%(1.2%,7.1%)and 2.9%(1.5%,60.4%),respectively,and there was no significant difference in platelet inhibition between different doses of aspirin(P=0.174).(2)The incidence of AR was 9.75%(23/236)in the highdose aspirin group and 8.05%(19/236)in the low-dose aspirin group. There was no significant difference in the incidence of AR between the two groups(P=0.617).(3)In the 19 children with AR and 217 children with aspirin sensitivity(AS)in oral low-dose aspirin treatment group,the age,sex,coagulation,biochemistry and other related indexes did not significantly differ between the two groups. CONCLUSION: The antiplatelet aggregation function of aspirin in KD children is not related to the dosage. AR is present in the treatment of Kawasaki disease,and the incidence of aspirin resistance is not related to dosage.

The role of evidence-based algorithms for rotational thromboelastometry-guided bleeding management / 대한마취과학회지

Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management (‘theranostic’ approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient's safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

Platelet function tests: A 5-year audit of platelet function tests done for bleeding disorders in a tertiary care center of a developing country

Introduction: The platelet function disorders remain largely undiagnosed or incompletely diagnosed in developing nations due to lack of availability of tests like lumiaggregometry, granule release assay or molecular testing. We performed a retrospective analysis of all the platelet function test (PFT) carried out in past 5 years by Light transmission aggregometery (LTA) using a panel of agonist. The indications and the test results were analyzed by two hematopathologist with the aim to look into the present diagnostic facilities or lack of it for correct diagnosis. This is essential for better management and genetic counselling. Materials and Methods: The PFT was performed both on patients and healthy unrelated age specific controls by light transmission aggregometry on Chronolog platelet aggregometer using platelet rich plasma. The panel of agonists included ADP (10?m/l and 2.0 ?m/l), epinephrine (10.0 ?m/l), collagen (2?g/ml), arachidonic acid (0.75 mM) and ristocetin (1.25 mg/ml & 0.25 mg/l). Results: The 5 years records of 110 cases were audited, 101 of these were tested for clinical bleeding , 35 adults and 66 children. The adults included 29 women and 6 men, 17 to 82 years of age. The children were 16 years to 3 months of age, 30 girls and 36 boys. Platelet function test abnormality was found in 31.6% (32/101) cases ,a majority remained undiagnosed of these about 21% had clinically significant bleeding.The cases diagnosed included Glanzmann Thromboasthenia-11 , von Willebrand Disease-6, Bernard Soulier'syndrome-1, storage pool disorder-6, mild defect of Epinephrine-3, isolated defect with collagen in1. Conclusion: An epidemiologically large proportion of platelet function disorders amongst people living in developing nations remain undiagnosed. This lacunae needs to be highlighted and addressed on larger scale. The options available are to increase the available armamentarium of tests or international collaboration with a specialized laboratory to aid in complete diagnosis.

Monitoring of antiplatelet therapy and changes of mean platelet volume after percutaneous coronary intervention in the patients with coronary heart disease / 临床检验杂志

Objective To compare the consistency of thrombelastography (TEG) and light transmittance aggregometry (LTA) in monitoring the antiplatelet therapy of the patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI),and observe the changes of mean platelet volume (MPV) of the patients treated with aspirin and clopidogrel after PCI.Methods A total of 177 patients undergoing PCI and the treatment of aspirin and clopidogrel in Peking University First Hospital during March 2014 and May 2015 were enrolled in the study.Their adenosine diphosphate (ADP) or arachidonic acid (AA) induced platelet inhibition rates determined by TEG,MPV before and after antiplatelet therapy,and the maximum platelet aggregation rates measured by LTA from 99 patients were retrospectively analyzed.Results There was no any correlation between the maximum aggregation rates measured by LTA and the platelet inhibition rates determined by TEG regardless of using ADP or AA as agonist (all P ＞ 0.05).The detection rates of clopidogrel hyporesponsiveness determined by LTA and TEG were 30.3％ and 45.5％,respectively,while those of aspirin hyporesponsiveness were 19.2％ and 31.3％,respectively.The detection rate of hyporesponsiveness determined by LTA was significant lower than that by TEG (P ＜ 0.05).The MPVs after antiplatelet therapy were significant lower than that before treatment (all P ＜ 0.01) regardless of clopidogrel hyporesponsive or sensitive and aspirin hyporesponsive or sensitive.The MPVs in clopidogrel hyporesponsive group before and after treatment were significantly lower than that in clopidogrel sensitive group (all P ＜ 0.05).The PLT counts in clopidogrel or aspirin hyporesponsive groups after treatment were significantly higher than that before treatment (all P ＜ 0.05).Conclusion There is poor correlation between LTA and TEG.It should be noted that the incidence rate of antiplatelet drug hyporesponsiveness is high in clinical practice.The MPVs of the patients significantly decrease after antiplatelet therapy.The patients with a significant increase of PLT after antiplatelet therapy are more likely to become drug hyporesponsiveness,while the patients with lower MPV are more likely to have clopidogrel hyporesponsiveness.

Efficacy and safety of ticagrelor plus cilostazol in the treatment of patients with low body weight after percutaneous coronary intervention / 中国介入心脏病学杂志

Objective To explore the efficacy and safety of ticagrelor plus cilostazol of different dosage in the treatment of low-weight patients after PCI.Methods A total of 148 consecutive ACS patients (body weight ≤ 65 kg) past PCI and with aspirin intolerance were enrolled and randomly divided into four groups.Patients given cilostazol 50mg twice daily plus clopidogrel 75 mg daily were named as the CC50 mg group.Patients in the CC100 mg group were given cilostazol 100 mg twice daily plus clopidogrel 75 mg daily.The TCS0 mg group were given cilostazol 50 mg twice daily plus standard ticagrelor 90mg twice daily and the TC100 mg group were given cilostazol 50 mg twice daily plus standard ticagrelor 90 mg twice daily.All patients were followed up clinically for 6 months.The clinical endpoints were MACEs and bleeding events.Platelet aggregation at 7 and 30 days after treatment the incidence of clinical endpoints during followup were compared between the four groups.Results Patients in the TC100mg group had the lowest platelet aggregation rates tested on both the 7th and 30th day after treatment among all the 4 groups.After 6 months of follow up,the MACEs rate was not significantly different between the four groups (P =0.930).Bleeding events rates in the TC100 mg group the highest among the 4 but without groups significant differences.Conclusions In ACS patients with low body weight ≤ 65 kg) past PCI and with aspirin intolerance,cilostazol 50mg twice daily plus ticagrelor is a safe and efficacious therapeutic regimen.

Simulation in coagulation testing using rotational thromboelastometry: A fast emerging, reliable point of care technique.

Computer simulations can come in handy to train medical personnel with necessary skills to face the clinical scenarios involving various coagulopathies. Now a days, point of care (POC) devices such as thromboelastography, Sonoclot analyzer and newly approved rotational thromboelastometry (ROTEM) with faster results to assess coagulopathies are available on bedside of patients. ROTEM is emerging as a quick, portable, and well‑validated device to evaluate coagulopathy in critical care and perioperative setup. A novel platelet‑aggregometry integrated module enables simultaneous analysis of platelets as well as coagulation tests on the same screen. The entire gamut of POC signature curves obtained with different coagulation defects can be learned with graphical simulations. These simulations can be a valuable strategy to elucidate latent conditions, for which simulation interventions can then be designed to mimic different clinical scenarios.

Monitoring the Antiplatelet Effect of Cilostazol with Light Transmission Aggregometer: Two Cases of Possible Cilostazol Resistance

BACKGROUND: Coronary artery disease is an important cause of death in adults and stent insertion is one of the treatment modalities. The most severe adverse effect of a stent insertion is the formation of a thrombus; therefore, antiplatelet agents are used. The addition of cilostazol to low-dose aspirin and clopidogrel results in a better antiplatelet effect. However, laboratory tests to monitor the effect of cilostazol are insufficient. METHODS: We tested the inhibitory effect of cilostazol using maximal platelet aggregation in 20 healthy volunteers. Conditions for incubation and concentrations of cilostazol and prostaglandin E1 (PGE1) were established and aggregation was induced by 5'-adenosine diphosphate (ADP) and measured with light transmission aggregometry (LTA). Blood samples were incubated with 1 µM and 2 µM cilostazol for 10 minutes at room temperature, and 80 nM PGE1 was added and incubated for an additional 10 minutes. Aggregation was induced by ADP and reactivity was evaluated. RESULTS: The average maximum aggregation (MA) was 58.1% at 1 µM cilostazol and 22.0% when PGE1 was added. The average MA was 42.8% when cilostazol concentration was increased to 2 µM and 21.2% when PGE1 was added. Average inhibition of aggregation at 1 µM cilostazol was not statistically significant (P=0.085), but was significant (P=0.004) at 2 µM cilostazol. Aggregation was not inhibited even with 2 µM cilostazol and PGE1 in 2 volunteers, which suggests possible resistance to cilostazol. CONCLUSIONS: We designed a method to monitor the effect of cilostazol using in vitro incubation with PGE1.

CD62pUsing Light Transmission Aggregometry and Flow Cytometry to Examine the Effect of Clopidogrel / 现代检验医学杂志

Objective To detect clopidogrel effect with light transmission aggregometry (LTA)and flow cytometry (FC). Methods ①Venous blood samples were taken from 71 inpatient with acute corotary syndrome (ACS)in PLA General Hos-pital,including unstable anqina,ST segment elevation myocardial infarction and non ST segment elevation myocardial infarc-tion (46 males,25 females)by random number table from June 2011 to March 2012,whose average age was 69(57~92).②All of them were served 160 mg aspirin and 300 mg clopidogrel after they were in hospital in the beginning,and then served with 75 mg/d clopidogrel for 6 months.On some day,firstly,they were required withdrawing drug for 10 days,and then ve-nous blood samples were separately taken from them before their served-clopidogrel again and their severd-clopidogrel 2 hours later.③The samples were assayed with LTA and FC simultaneously and the platelet aggregation rates before served-clopidogrel (ADPLTA-before serving ),platelet aggregation rates after served-clopidogrel (ADPLTA-after serving ),inhibition rates (ADPLTA-INDU ),PAC-1 activity percentage before served-clopidogrel (PAC-1 before serving ),PAC-1 activity percentage after served-clopidogrel (PAC-1 after serving ),inhibition rates (PAC-1 INHI ),CD62p activity percentage before served-clopidogrel (CD62pbefore serving ),CD62pactivity percentage after served-clopidogrel (CD62pafter serving ),inhibition rates (CD62pINHI )weregotten.All volunteers were signed informed consents and the experiment was approved by the hospital ethics committee.Re-sults ①The paired samples t-test was (t=-2.082,P =0.041)between ADPLTA-before serving (0%~97%)and ADPLTA-after serving (12%~97%),the paired samples t-test was (t = 3.663,P < 0.01)between PAC-1 before serving (15.1% ~ 78.9%)and PAC-1 after serving (14.5% ~ 78.3%);the paired samples t-test was (t = 2.082 and P = 0.041)between CD62pbefore serving (1.5% ~80.8%)and CD62pafter serving (1.4%~41.4%).②The pearson coeffcient correlation results were:ADPLTA-INDU (0%~28.2%) and PAC-1 INHI (0.6%~ 9.1%)(r = 0.297,P = 0.012);ADPLTA-INDU (0% ~ 28.2%)and CD62pINHI (0.1% ~ 48.5%)(r =0.220,P =0.065);PAC-1 INHI (0.6%~9.1%)and CD62pINHI (0.1%~48.5%)(r=0.736,P <0.001).Conclusion Because the correlation was bad between the inhibition rates of clopidogrel detected by FC and them by LTA,FC didn’t apply to clin-ical routine examination of the platelet aggregation.But it could be used to scientific researchs and auxiliary confirmation of routine examination results.

Comparatively Study on the Thromboelastography and Light Transmission Aggregometry in Monitoring Clopidogrel Effect / 现代检验医学杂志

Objective To comparatively study the difference between thromboelastography (TEG)and light transmission ag-gregometry (LTA)in monitoring clopidogrel effect in patients with acute coronary syndrome.Methods 68 patients with a-cute coronary syndrome,who were in hospital from February to December 2013,were enrolled in this study.They received TEG and LTA to determine platelet aggregation.Results Clopidogrel effect was (47.84±26.04)% and (45.64±20.92)%respectively by TEG and LTA.There were negative correlation between LTAADP and TEGADP(r=-0.752,P<0.001),pos-itive correlation between LTAADP and MAADP(r=0.789,P<0.001),negative correlation between TEGADP and MAADP(r=-0.820,P<0.001).Conclusion There was a good correlation between the two methods.TEG can be used to evaluate thera-peutic effect of Clopidogrel effect.

Utilidad clínica de la agregometría plaquetaria / Clinical utility of platelet aggregometry

Resumen: La acción de las plaquetas en la hemostasia primaria comprende la adhesión a losvasos sanguíneos afectados, la activación, la secreción del contenido granular, y posteriormente,la agregación plaquetaria para la formación del tapón hemostático primario. Bajo las condicionesfisiológicas de flujo vascular, estos procesos requieren la acción sinérgica de varias proteínasy receptores plaquetarios, como también de agonistas que inducen la activación plaquetaria.Por ello, las mutaciones de los genes que codifican para moléculas y receptores de superficieimplicados en estos procesos darán origen a desórdenes hemorrágicos como la enfermedad devon Willebrand, la trombastenia de Glanzmann, el síndrome de Bernard Soulier y la deficienciade gránulos plaquetarios, entre otros. El diagnóstico de estas enfermedades se realiza medianteensayos de función plaquetaria que simulan los procesos fisiológicos de activación, adhesión,liberación del contenido granular y agregación. Una de las pruebas de función plaquetaria másutilizada es la agregometría. En este artículo de revisión se describe la utilidad de esta prueba parael diagnóstico de desórdenes hemorrágicos hereditarios y del síndrome de la plaqueta pegajosa,un desorden trombótico hereditario caracterizado por hiperagregabilidad. Adicionalmente, se revisa el fundamento de esta prueba, las condiciones preanalíticas, analíticas y posaanaliticas, analiticas y poanaliticas las indicaciones las contraindicaciones y la interpetación de los resultados.

Abstract: The role of platelets in primary hemostasis involves their adherence to sites of vessel injury, activation, secretion of platelet granule content, and finally, aggregation to form the primaryhemostatic plug. Under physiologic conditions of vascular flow, these processes require thesynergistic action of several proteins and platelet receptors, and also the action of physiologicalagonists that stimulate the activation of the platelets. As a result, hereditary mutations of genescodifying for molecules and surface receptors implied in primary hemostasis will be expressedas hemorrhagic disorders, including von Willebrand disease, Glanzmann thrombasthenia,Bernard Soulier syndrome, storage pool diseases, among others. The diagnosis of these diseases is possible through platelet function assays that resemble the physiological processesof activation, adhesion, release of granule content, and aggregation. Platelet aggregometry isone of the most frequently used tests. This review article intends to describe the utility of plateletaggregometry for the diagnosis of hereditary hemostatic disorders and sticky platelet syndrome, a hereditary thrombotic disorder characterized by increased platelet aggregability. In addition, the fundamentals of the test, the pre-analytical, analytical and post-analytical conditions, the test indications, contraindications and results interpretation are discussed.

Diferencias en la agregación plaquetaria de sangre coronaria y periférica de pacientes con enfermedad coronaria: implicaciones clínicas / Differences in platelet aggregation in coronary and peripheral blood of patients with coronary disease: clinical implications

INTRODUCCIÓN: los fenómenos trombóticos son más frecuentes en las coronarias y, al parecer, los cambios que produce la enfermedad aterosclerótica en la reología y en la superficie endotelial son los responsables de este fenómeno. OBJETIVO: cuantificar la diferencia en la agregación plaquetaria de sangre venosa coronaria y sangre venosa periférica en pacientes con enfermedad coronaria severa. METODOLOGÍA: se seleccionaron pacientes mayores de treinta años, con enfermedad coronaria severa, de quienes se obtuvieron muestras de sangre periférica y del seno coronario, y se realizaron agregaciones plaquetarias por el método de absorbancia con ADP 10 mmol, ácido araquidónico (AA), epinefrina (Epi) 300 mmol y colágeno 10 mg/mL. RESULTADOS: se incluyeron en total 32 pacientes con edad promedio de 65 más o menos 10 años, 22 hombres, 10 (31 porciento) pacientes con enfermedad estable y 22 (69 porciento) con inestable. La agregación plaquetaria en sangre del seno coronario fue mayor con todos los agonistas usados, así: ADP 61,8 porciento vs. 53,4 porciento (p= 0,001), AA 15,1 porciento vs. 13,8 porciento (p= 0,48), colágeno 72,6 porciento vs. 69,2 porciento (p= 0,048) y Epi 58 porciento vs. 51,6 porciento (p= 0,01). Los pacientes con enfermedad inestable muestran una mayor agregación con ADP en el seno coronario: 58,5 porciento vs. 49,2 porciento (p= 0,001) y no hay diferencias en los inestables. La resistencia a la Aspirina fue similar (p= 1), sin embargo la resistencia al clopidogrel fue mayor en el seno coronario: 56 porciento vs. 48 porciento (p= 0,24).

INTRODUCTION: thrombotic events are more frequent in the coronary arteries and apparently the changes in rheology and endothelial surface produced by atheroesclerotic disease are responsible for this phenomenon. OBJETIVE: quantify the difference in platelet aggregation of coronary venous blood and peripheral venous blood in patients with severe coronary disease. METHODOLOGY: we selected patients older than 30 years with severe coronary disease and obtained samples of peripheral and coronary sinus blood. Platelet aggregation was realized by the absorbance method with ADP 10 mmol, arachidonic acid (AA), epinephrine (Epi) 300 mmol and collagen 10 ug/mL. RESULTS: we included a total of 32 patients with mean age 65 more or less 10 years. 22 were men; 10 patients (31 percentage) had stable disease and 22 (69 percentage) unstable disease. Platelet aggregation in coronary sinus blood was higher with all agonists used as follows: ADP 61.8 percentage vs. 53.4 percentage (p = 0.001), AA 15.1 percentage vs.13.8 percentage (p = 0.48), collagen 72.6 percentage vs. 69.2 percentage (p = 0.048) and Epi 58 precentage vs. 51.6 percentage (p = 0.01). Patients with unstable disease show increased aggregation with ADP in the coronary sinus 58.5 percentage vs. 49.2 percentage (p = 0.001) and there are no differences in the unstable. Aspirin resistance was similar (p = 1); however, clopidogrel resistance was higher in the coronary sinus 56 percentage vs. 48 percentage (p = 0.24). CONCLUSION: we describe the presence of higher platelet aggregation in the coronary sinus of patients with atheroesclerotic disease that is significant for ADP, collagen and epinephrine, and suggest the appearance of local factors associated with the coronary disease that increase platelet aggregation. Peripheral platelet aggregation doesn't reflect the local behavior in patients with coronary atheroesclerosis.

Inibição e reversão da agregação plaquetária de eqüinos in vitro com o uso de ketoprofeno, fenilbutazona e flunixim meglumine / In vitro inibition and reversion of equine platelet aggregation using ketoprophen, phenylbutazone and flunixin meglumin

Como são várias as enfermidades e os distúrbios que induzem à hipercoagulabilidade e à pré-ativação de plaquetas em eqüinos. A atividade de medicamentos utilizados para controle dessas enfermidades sobre a agregação de plaquetas pode, não apenas servir para avaliar sua evolução, como também a resposta terapêutica. Com o objetivo de avaliar a prevenção e a reversão da agregação plaquetária de eqüinos in vitro foram utilizados os antiinflamatórios não esteroidais (AINES): ketoprofeno, fenilbutazona e flunixim meglumine. A comparação demonstrou que a fenilbutazona e o ketoprofeno previnem a agregação de plaquetas de eqüinos induzida pelo ADP, de forma mais eficaz do que o flunixim-meglumine e, superior ao fragmento monoclonal de anticorpo Reopro, sendo semelhante a dos bloqueadores de receptores de membrana Ro-438857 e RGDS. Quanto a reverão da agregação plaquetária tanto a fenilbutazona quanto o ketoprofeno demonstraram efeitos dose-dependente.

Several diseases may lead to platelet pre-activation and hypercoagulability states in horses. The activity of many drugs against platelet aggregation may, not only contribute to the evaluation of a disease but also its response to the therapy. With the aim to study in vitro prevention and reversion of platelet aggregation, the non steroidal anti-inflammatory drug (NSAID): ketoprophen, phenylbutazone and flunixin-meglumin were evaluated. The comparison demonstrated that phenylbutazone and ketoprophen prevented platelet aggregation induced by ADP better than flunixin-meglumin, in a superior manner to the monoclonal antibody Reopro, and in a better way than the membrane receptor blockers Ro-438857 and RGDS. The reversion of platelet aggregation demonstrated that even phenylbutazone or ketoprophen have a dose-dependent effect.