El volumen medioplaquetario: su importancia en la práctica clínica / Mean platelet volume: its importance in clinical practice

Las plaquetas son fragmentos citoplasmáticos anucleados derivados de los megacariocitos que presentan función central, tanto en procesos fisiológicos como la hemostasia, así como también en procesos patológicos como la inflamación, la ateroesclerosis. El tamaño de las plaquetas, medido como volumen medio de plaquetas, es un marcador de reactividad plaquetaria, que proporciona información importante sobre el curso y pronóstico de una variedad de afecciones inflamatorias. El estudio de este marcador se ha utilizado como pronóstico en enfermedades cardiovasculares, preeclampsia y en la púrpura trombocitopénica. El objetivo de este trabajo es revisar los conceptos actuales basados en la evidencia científica relacionados con el volumen plaquetario medio e insistir en su evaluación y significado en la práctica clínica cotidiana(AU)

Platelets are enucleated cytoplasmic fragments derived from megakaryocytes, which have a central function, both in physiological processes such as hemostasis, as well as in pathological processes such as inflammation, atherosclerosis. Platelet size, measured as mean volume of platelets, is a marker of platelet reactivity, providing important information on the course and prognosis of a variety of inflammatory conditions. The study of this marker has been used as a prognostic in cardiovascular diseases, preeclampsia and in thrombocytopenic purpura. The objective of this paper is to review the current concepts based on scientific evidence related to the mean platelet volume and to insist on its evaluation and meaning in daily clinical practice(AU)

Performance of a Hematological Scoring System in Predicting All-Cause Mortality in Patients with Acute Myocardial Infarction

Abstract Background: The presence of nucleated red blood cells (NRBCs) and increases in mean platelet volume (MPV) and neutrophil to lymphocyte ratio (NLR) in peripheral circulation are associated with poorer prognosis in patients with acute coronary disease. Objective: We developed a scoring system for in-hospital surveillance of all-cause mortality using hematological laboratory parameters in patients with acute myocardial infarction (AMI). Methods: Patients admitted for AMI were recruited in this prospective study. Exclusion criteria were age younger than 18 years, glucocorticoid therapy, cancer or hematological diseases and readmissions. NRBCs, MPV and NLR were measured during hospitalization. The scoring system was developed in three steps: first, the magnitude of the association of clinical and laboratory parameters with in-hospital mortality was measured by odds ratio (OR), second, a multivariate logistic regression model was conducted with all variables significantly (p < 0.05) associated with the outcome, and third, a β-coefficient was estimated by multivariate logistic regression with hematological parameters with a p < 0.05. Results: A total of 466 patients (mean age were 64.2 ± 12.8 years, 61.6% male) were included in this study. A hematological scoring system ranging from 0 to 49, where higher values were associated with higher risk of in-hospital death. The best performance was registered for a cut-off value of 26 with sensitivity of 89.1% and specificity of 67.2%, positive predictive value of 26.8% (95% CI: 0.204 - 0.332) and negative predictive value of 97.9% (95% CI: 0.962 - 0.996). The area under the curve for the scoring system was 0.868 (95% CI: 0.818 - 0.918). Conclusions: Here we propose a hematological scoring system for surveillance tool during hospitalization of patients with acute myocardial infarction. Based on total blood count parameters, the instrument can evaluate inflammation and hypoxemia due to in-hospital complications and, consequently, predict in-hospital mortality.

Platelet/lymphocyte ratio and mean platelet volume in patients with granulomatosis with polyangiitis

Abstract Background: Granulomatosis with polyangiitis (GPA) is a granulomatous necrotizing vasculitis with high morbidity and mortality. Anti-neutrophil cytoplasmic antibody is a valuable diagnostic marker, however its titer lacks predictive value for the severity of organ involvement. Platelet to lymphocyte ratio (PLR) and mean platelet volume (MPV) has been regarded as a potential marker in assessing systemic inflammation. We aimed to explore the value of PLR and MPV in the assessment of disease activity and manifestations of disease in GPA. Methods: 56 newly diagnosed GPA patients and 53 age-sex matched healthy controls were included in this retrospective and cross-sectional study with comparative group. Complete blood count was performed with Backman Coulter automatic analyzer, erythrocyte sedimentation rate (ESR) with Westergen method and C-reactive protein (CRP) levels with nephelometry. The PLR was calculated as the ratio of platelet and lymphocyte counts. Result: Compared to control group, ESR, CRP and PLR were significantly higher and MPV significantly lower in GPA patients. In patients group, PLR was positively correlated with ESR and CRP (r = 0.39, p = 0.005 and r = 0.51, p < 0.001, respectively). MPV was negatively correlated with ESR and CRP (r = - 0.31, p = 0.028 and r = - 0.34 p = 0.014, respectively). Patients with renal involvement had significantly higher PLR than patients without renal involvement (median:265.98, IQR:208.79 vs median:180.34 IQR:129.37, p = 0.02). PLR was negatively correlated with glomerular filtration rate (r = - 0.27, p = 0.009). A cut-off level of 204 for PLR had 65.6% sensitivity and 62.5 specificity to predict renal involvement. Conclusion: PLR exhibit favorable diagnostic performance in predicting renal involvement in patients with GPA.(AU)

Clinical Significance of Platelet Volume and Other Platelet Parameters in Acute Myocardial Infarction and Stable Coronary Artery Disease / Significado Clínico do Volume Plaquetário e Outros Parâmetros Plaquetários no Infarto Agudo do Miocárdio e Doença Arterial Coronariana Estável

Abstract Background: Platelets are important in the initiation of thrombosis, and their morphological and functional changes are closely related with the occurrence and development of coronary artery thrombosis. Platelet parameters might be valuable in distinguishing between acute myocardial infarction (AMI) and stable coronary artery disease (SCAD). Objective: This study was designed to detect and compare changes in platelet parameters, such as mean platelet volume (MPV) in patients with acute myocardial infarction (AMI) and stable coronary artery disease (SCAD) and to investigate their roles in these diseases. Methods: Specimen collection: Between January 2011 and December 2013, 2 mL of elbow vein blood was drawn from each of 31 patients primarily diagnosed with AMI, 34 SCAD patients and 50 healthy subjects; and placed in EDTA-K2 anticoagulant tubes. Platelet count (PLT), MPV, plateletcrit (PCT), platelet distribution width (PDW), white blood cell (WBC) and neutrophil (NEU) counts were determined using an STKS automated hematology analyzer (Beckman Courter). Results: Compared with the control group, MPV levels were significantly higher in the AMI and SCAD groups (p < 0.05), while PLT was significantly lower (p < 0.05). Conclusion: These results suggest that MPV and other related parameters have a certain value in the diagnosis of SCAD and AMI.

Resumo Fundamento: As plaquetas são importantes no início da trombose e suas alterações morfológicas e funcionais estão intimamente relacionadas com a ocorrência e o desenvolvimento de trombose da artéria coronária. Os parâmetros plaquetários podem ser valiosos na distinção entre infarto agudo do miocárdio (IAM) e doença arterial coronariana estável (DACE). Objetivo: O objetivo desse estudo foi detectar e comparar alterações nos parâmetros plaquetários, como o volume plaquetário médio (VPM) em pacientes com infarto agudo do miocárdio (IAM) e doença arterial coronariana estável (DACE) e investigar seu papel nessas doenças. Métodos: Coleta de amostras: Entre janeiro de 2011 e dezembro de 2013, foram retirados 2 mL de sangue da veia do antebraço de cada um dos 31 pacientes diagnosticados principalmente com IAM, 34 pacientes com DACE e 50 indivíduos saudáveis; e colocado em tubos com anticoagulante EDTA-K2. As contagens de plaquetas (PQT), VPM, massa total de plaquetas (MTP), Amplitude de Distribuição de Plaquetas (PDW, do inglês platelet distribution width), contagem de glóbulos brancos (WBC, do inglês white blood cells) e neutrófilos (NEU) foram determinadas utilizando-se um analisador de hematologia automatizado STKS (Beckman Courter). Resultados: Comparado com o grupo controle, os níveis de VPM foram significativamente maiores nos grupos IAM e DACE (p < 0,05), enquanto os níveis de PQT foram significativamente menores (p < 0,05). Conclusão: Esses resultados sugerem que o VPM e outros parâmetros associados têm um certo valor no diagnóstico de DACE e IAM.

Estigma social e estigma internalizado: a voz das pessoas com transtorno mental e os enfrentamentos necessários / Social stigma and internalized stigma: the voice of persons with mental disorders and the confrontations required

Resumo O estigma internalizado ocorre quando o indivíduo tem consciência do estigma a ele atribuído, concordando e aplicando a si próprio os estereótipos negativos sobre sua doença. A internalização do estigma agrava os sintomas do transtorno mental, levando a isolamento, sentimentos de baixa autoestima, culpa e autorreprovação. Buscou-se produzir mais conhecimentos acerca dessa temática, a partir da visão das pessoas com transtorno mental que participam de ações visando construir coletivamente soluções no cuidado em saúde mental. Com o objetivo de analisar o processo de estigma e estigma internalizado, realizou-se pesquisa qualitativa, com entrevistas semiestruturadas. Os resultados revelaram que o estigma internalizado tem efeitos negativos no indivíduo, e que a família tem forte influência nesse processo.

Abstract Internalized stigma occurs when individuals become aware of the stigma assigned to them, agree, and apply these negative stereotypes about their illness to themselves. The internalization of stigma aggravates the symptoms of mental disorders, leading to isolation, feelings of low self-esteem, guilt, and self-condemnation. Our goal was to produce more knowledge on this topic from the point of view of people with mental disorders who participate in activities aimed at collectively building mental health care solutions. With the objective of analyzing the process of stigma and internalized stigma, we carried out qualitative research using semi-structured interviews. The results showed that internalized stigma has negative effects on individuals, and that the family has a strong influence on this process.

Predictive value of mean platelet volume in saphenous vein graft disease

Abstract Objective: To determine whether mean platelet volume (MPV), platelet distribution width (PDW), and platelet count could be used as determinants of mortality following coronary artery bypass graft (CABG) surgery and patency of saphenous vein grafts (SVG). Methods: The records of 128 patients who underwent emergency or elective coronary angiography after CABG surgery, and who died at an early stage were retrospectively reviewed. Patients were divided into three groups as early death, no SVG disease (SVGD), and SVGD group. MPV, PDW, and platelet count were evaluated at different times. Results: MPV was significantly higher in the stenotic group than in the nonstenotic group (9.7±1.8 fl and 8.2±0.9 fl, P<0.05). The postoperative MPV ratio was found to be higher in the stenotic group when compared to the preoperative period (9.6±1.8 fl and 7.8±0.9 fl, P<0.05). MPV values were also found to be higher in patients who died during the early stage than in surviving patients (9.4±1.9 fl and 8.0±1.0 fl, P<0.05). There was no statistically significant difference regarding platelet count and PDW ratios between the early deaths group and surviving patients. An MPV value higher than 10.6 predicted SVGD with 85% sensitivity and 45% specificity; and an MPV higher than 7.9 predicted early death with 80% sensitivity and 68% specificity were observed. Conclusion: MPV may be a useful indicator for the prediction of SVGD and mortality following CABG surgery.

Platelets volume indexes and cardiovascular risk factors

SUMMARY Obesity, diabetes and hypertension are risk factors for cardiovascular diseases (CVD) because they promote a state of hypercoagulability. It is known that platelets play an important role in the development of atherosclerosis. Recent studies have evaluated platelet volume indexes (PVIs) in individuals with risk factors for CVD to better understand the platelet mechanisms involved in their development. The IVPs indirectly estimate platelet function and are easily obtained from automated hematology analyzers, which provide platelet counts, mean platelet volume (MPV), platelet distribution width (PDW) and the platelet-large cell ratio (P-LCR). The present study aims to review literature studies that investigated the association between PVIs and obesity, diabetes, and arterial hypertension, in order to evaluate its use as a potential subclinical marker of CVD. Studies have shown promising results for MPV, an index that allows for early detection of platelet activation and may be useful in identifying patients before the onset of CVD development so that preventive strategies can be implemented. The PDW, although evaluated by a smaller number of studies, also showed promising results. However, there is still a long way to go in order for the MPV and PDW to be used in clinical practice, since there is still a need for more epidemiological evidence, establishing reference values, and standardizing the way results are presented.

RESUMO A obesidade, o diabetes e a hipertensão arterial são fatores de risco para as doenças cardiovasculares (DCV) por promoverem um estado de hipercoagulabilidade. É sabido que as plaquetas desempenham um importante papel no desenvolvimento da aterosclerose. Diante disso, estudos recentes têm avaliado os índices de volumes plaquetários (IVPs) em indivíduos com fatores de risco para DCV, para melhor se entenderem os mecanismos plaquetários envolvidos no seu desenvolvimento. Os IVPs estimam indiretamente a função plaquetária e são facilmente obtidos a partir de analisadores hematológicos automáticos, que fornecem contagens de plaquetas, volume médio de plaquetas (VPM), largura de distribuição de plaquetas (PDW) e a proporção de plaquetas grandes (P-LCR). O presente trabalho tem por objetivo revisar na literatura estudos que investigaram a associação entre os IVPs e obesidade, diabetes e hipertensão arterial, a fim de avaliar o seu uso como potencial marcador subclínico das DCV. Estudos demonstraram resultados promissores quanto ao VPM, um índice que permite uma detecção precoce da ativação de plaquetas e que pode ser útil na identificação de pacientes antes do início do desenvolvimento de DCV, de tal forma que estratégias preventivas possam ser implantadas. O PDW, embora tenha sido avaliado por um número menor de estudos, também demonstrou resultados promissores. Entretanto, ainda existe um longo caminho a se percorrer para que o VPM e o PDW sejam utilizados na prática clínica, pois ainda são necessárias mais evidências epidemiológicas, o estabelecimento de valores de referência e a padronização da forma de expressar os resultados.

Altered mean platelet volume in patients with polymyositis and its association with disease severity

Polymyositis (PM) is an autoimmune disease characterized by chronic inflammation in skeletal muscle. Mean platelet volume (MPV), a marker in the assessment of systemic inflammation, is easily measured by automatic blood count equipment. However, to our knowledge, there are no data in the literature with respect to MPV levels in PM patients. Therefore, in this study we aimed to investigate MPV levels in patients with PM. This study included 92 newly diagnosed PM patients and 100 healthy individuals. MPV levels were found to be significantly lower compared with healthy controls (10.3±1.23 vs 11.5±0.74 fL, P<0.001). Interestingly, MPV was found to be positively correlated with manual muscle test (MMT) score and negatively correlated with erythrocyte sedimentation rate (ESR) in patients with PM (r=0.239, P=0.022; r=−0.268, P=0.010, respectively). In addition, MPV was significantly lower in active PM patients compared with inactive PM patients (9.9±1.39 vs 10.6±0.92 fL, P=0.010). MPV was independently associated with PM in multivariate regression analyses, when controlling for hemoglobin and ESR (OR=0.312, P=0.031, 95%CI=0.108 to 0.899). The ROC curve analysis for MPV in estimating PM patients resulted in an area under the curve of 0.800, with sensitivity of 75.0% and specificity of 67.4%. Our results suggest that MPV is inversely correlated with disease activity in patients with PM. MPV might be a useful tool for rapid assessment of disease severity in PM patients.

Evaluation of plasma eosinophil count and mean platelet volume in patients with coronary slow flow

OBJECTIVE: The pathophysiology of coronary slow flow has not been clearly defined, although multiple abnormalities including arteritis, endothelial dysfunction, and atherothrombosis, have been reported. It is known that eosinophils play an important role in inflammation, endothelial dysfunction, and thrombosis. We aimed to compare the eosinophil counts of coronary slow flow patients versus healthy controls. METHODS: This study included 50 coronary slow flow patients (19 males, mean age 65.6±13.7 years) and 30 healthy controls (10 males, mean age 57.86±11.6 years). These participants were evaluated using concurrent routine biochemical tests as well as neutrophil, lymphocyte, and eosinophil counts and mean platelet volume (MPV), which were obtained from the whole blood count. These parameters were compared between groups. RESULTS: The baseline characteristics of the study groups were comparable. The coronary slow flow patients had a higher mean platelet volume and eosinophil count than the control group (8.38±0.86 vs 6.28±1.6 fL and 0.31±0.42 vs 0.09±0.05; p<0.001 and 0.008, respectively). CONCLUSION: Our study demonstrated a relationship between eosinophil count and MPV in patients with coronary slow flow. .