Mean platelet volume and mean platelet volume/platelet count ratio in infective endocarditis

Abstract

Infective endocarditis (IE), an infection of the endocardial surface, frequently leads to life-threatening complications, such as thromboembolism due to platelet activation. We investigated the mean platelet volume (MPV) in Korean patients with IE and the serial changes thereof, in comparison with other laboratory parameters. We analyzed 248?MPV results from 22 patients diagnosed with IE in our hospital between January 2011 and April 2012. MPV was measured with an Advia 2120 (Siemens Healthcare Diagnostics, Tarrytown, NY) using EDTA-containing tubes. The mean MPV differed significantly between the patient and control groups, 8.74 vs. 7.96?fl, respectively. In addition, the platelet count and MPV/platelet count ratio were significantly decreased in the patient group. The total platelet mass and platelet size in IE might be increased. Further studies should examine more patients to verify the changes in the MPV and MPV/platelet count ratio in IE and assess in greater detail the relationship between MPV and thrombotic complications caused by platelet activation.     

Mean platelet volume/platelet count ratio in hepatocellular carcinoma

Mean platelet volume (MPV) has been actively investigated in liver disease such as steatosis, cirrhosis and hepatitis. Recently, MPV/platelet count (PC) ratio has been proposed as a predictor of long-term mortality after myocardial infarction. As PC is known to be decreased in various liver diseases such as cirrhosis, hepatosplenomegaly and malignancy, we planned to evaluate MPV/PC ratio in patients with hepatocellular carcinoma (HCC) in this study. Mean of MPV levels showed significant difference, which were 8.69?fl (range 6.7–12.2?fl) in patients group and 8.02?fl in control group (range 6.7–11.0?fl). In receiver operating characteristic (ROC) curve analysis, the MPV/PC ratio (fl/(10⁹/l)) presented 74.5% of sensitivity and 96.5% of specificity at the criterion?>?0.0491 (area under the curve (AUC)?=?0.884), while MPV alone showed 57.4% of sensitivity and 81.4% of specificity at the criterion?>?8.4?fl. Further studies should evaluate underlying pathogenic mechanisms of MPV/PC ratio difference and various possibilities of this ratio as an indicator of presence of a tumor in HCC.     

Mean platelet volume: comparison of three analysers towards standardization of platelet morphological phenotype

Introduction: The aim of this study was to show variability in the measurement of the mean platelet volume (MPV) depending on the instrument used. Methods: This prospective analysis was carried out to measure MPV with three instruments, in 30 healthy controls and 113 hospital patients. Results: Firstly, for values in the normal range, the values obtained with the Siemens Advia^® 2120 are lower than those given by the Beckman Coulter LH750^® (?0.89), which are in turn lower than those obtained with the Sysmex XE‐2100D^® (?1.11), which represents a 20–25% variation in the measurement. These results emphasize the lack of universal external calibration for MPV analysis and thus make any intercentre comparison of MPV impossible unless the automated haematology analyser used is indicated. Secondly, we stress the differences in behaviour of the instruments in the presence of abnormally large platelets, i.e. an underestimate of the platelet count and the MPV may be provided because instruments using impedance technology may fail to take into account these platelets, but they rightly flag them. Conclusion: To harmonize our procedures, we propose definitions of platelet size (normal size, macroplatelets and giant platelets) based on the coordinated interpretation of the MPV, the distribution of platelet volume and the morphological appearance.     

Mean platelet volume in acute rheumatic fever

Acute rheumatic fever (ARF) is still an endemic disease, especially among school-aged children in developing countries. Mean platelet volume (MPV), which is commonly used as a measure of platelet size, indicates the rate of platelet production and platelet activation. We aimed to investigate MPV in children with ARF. The study population consisted of 40 children with ARF (32 patients with carditis and 8 patients without carditis) and 40 healthy control subjects. White blood cell (WBC) and platelet counts were significantly higher and MPV values were significantly lower in patients with ARF during the acute stage when compared to controls. Erythrocyte sedimentation rate (ESR) and C-reactive protein values significantly decreased in patients with ARF after the treatment when compared to baseline, whereas MPV values increased. MPV values were negatively correlated with ESR and WBC, and platelet counts. In conclusion, during the acute stage of ARF, MPV values were lower when compared to controls.     

New roles for mean platelet volume measurement in the clinical practice?

Several hundreds of studies recently investigated mean platelet volume (MPV) as measured by electronic cell counters in a wide variety of acquired diseases, and most of them found that platelet size was significantly increased with respect to healthy subjects. On this basis, it has been suggested that MPV can be used for diagnostic purposes. Moreover, investigation of subjects with arterial thrombosis not only revealed that their platelets were larger than those of controls, but also found that a high MPV predicted poor prognosis. Despite the large amount of available data, the pathogenesis of increased platelet size in these conditions is unclear. In particular, we do not know whether the increased platelet size is the cause or the consequence of thrombosis. Differences in MPV between patients and controls are usually very small and they reach the statistical significance because of the large number of investigated patients and the standardized methodology for MPV measurement. In real life, the wide variability of MPV possibly due to platelet count, sex, age, and ethnicity, as well as the very poor standardization of the methodologies used for MPV measurement, makes it impossible to decide whether an individual patient has normal or instead slightly increased MPV. So, MPV has presently no role in making diagnosis and defining prognosis in any acquired illness.     

Mean platelet volume: Association with adverse neonatal outcome

The aim of the study was to investigate on a possible association between maternal mean platelet volume (MPV) and oxygen-metabolic changes in pregnancies affected by altered maternal-fetal Doppler velocimetry. We considered the altered maternal-fetal Doppler velocimetry group (n?=?57) pregnant women admitted to our Institution for a pregnancy complication associated to the event Pre-eclampsia (PE) and intrauterine growth retardation (IUGR), with altered Doppler velocimetry in the umbilical artery (?UA) (high pulsatility index, absence or reverse end diastolic flow (ARED), blood flow cephalisation) and/or bilateral increased resistance in uterine arteries. Out of these cases, 25 pregnancies were complicated by PE and 32 pregnancies were complicated by IUGR. We included 145 normotensive third trimester pregnant women as a normal maternal-fetal Doppler velocimetry control group. From all women, 20?ml of whole venous blood was obtained from the antecubital vein soon after Doppler velocimetry evaluation. MPV was significantly higher in women with abnormal Doppler velocimetry compared to those with normal Doppler velocimetry (8.0?fl [7.0–8.7] vs. 9.1?fl [8.0–10.6], <0.001. Values are median [interquartiles]). We performed a ROC curve in order to find an MPV cut-off able to predict an uneventful event in Doppler velocimetry compromised fetuses (neonatal O₂ support?>?48?hrs or intubation and/or pH?<?7.2 at umbilical blood gas analysis (UBGA)). An MPV?≥?10?fl was significantly related to the former diagnostic endpoints compared to that of non-compromised fetuses (sensitivity: 45%, specificity: 89.7%, 95 CI: 18.8–66, p?<?0.01). Our study suggests that pregnancies affected by Doppler velocimetry alterations, an MPV value?≥?10?fl may be associated with severe oxygen support and/or low UA ph at birth.     

Mean platelet volume in patients with subclinical hypothyroidism

Subclinical hypothyroidism (SCH) is frequently encountered in the general population. Since it is generally asymptomatic, these patients are mostly identified through routine screening or evaluation of non-specific symptoms. It has been suggested as a risk factor for cardiovascular disease. On the other hand, mean platelet volume (MPV), which is a determinant of platelet function, is an independent risk factor for cardiovascular disease. The aim of this study was to evaluate MPV values in subclinical hypothyroidic patients when they were subclinical hypothyroidic and became euthyroidic after 12 weeks of levothyroxine replacement therapy. Sixty patients with subclinical hypothyroidism and 78 euthyroid healthy subjects matched for age, gender and body mass index were enrolled in the study. None of the study subject had diabetes, hypertension or dyslipidemia. All the study subjects were evaluated by biochemical and platelet parameters. Subclinical hypothyroidic patients were then reevaluated with the same parameters when they became euthyroid after 12 weeks of levothyroxine treatment. Platelet counts and metabolic parameters, except serum triglyceride and high density lipoprotein cholesterol (HDLC) levels, were similar between the two groups. Serum triglyceride and MPV values were significantly higher (pTG?=?0.007 and pMPV?<?0.001) while HDLC levels were lower (pHDLC?=?0.008) in the subclinical hypothyroidic group. MPV was found to be correlated with only antithyroid peroxidase (anti-TPO) antibody levels (P?<?0.001). MPV values were decreased after subclinical hypothyroidic patients became eythyroid. However, post-treatment MPV values were still higher (p?=?0.035) in the patient group than in control group. These results suggest that subjects with SCH are susceptible to increased platelet activation and increased MPV values which contribute to increased risk of cardiovascular complications.     

Effects of cesarean section on mean platelet volume

Mean platelet volume (MPV) is a risk factor for cardiovascular complications, cerebrovascular disorders, and low-grade inflammatory conditions prone to arterial and venous thromboses. Cesarean delivery is the most important risk factor for pulmonary embolism, stroke, and intracranial venous thrombosis. The hypothesis is that increase in the prevalence of cesarean section and high MPV may be associated with cardiovascular complications such as stroke along with intracranial complications in addition to known systemic and surgical complications. In this study, platelet counts and MPV for postpartum women who delivered by cesarean section and normal vaginal parturition are compared. The subjects were divided in two groups, one was study group consisting of 118 patients giving birth by cesarean section and the other was the control group consisting 94 patients giving birth by normal vaginal parturition. Peripheral venous blood samples in EDTA tubes were collected from all the subjects 1 week before and after the delivery for their prenatal and postpartum periods, respectively. The values were compared between the groups and also before and after the delivery. In the cesarean group, while the MPV level was 8.60 (1.64) fl in the prenatal period, it increased to 9.10 (2.00) fl in the postnatal period (p?<?0.001). Group effect, time effect (independent from group effect), and group*time interaction effect were statistically significant for MPV variable (p?=?0.032, p?<?0.001, and p?=?0.012, respectively). This study concluded that MPV, along with several other factors, may be used as a prognostic, independent, and therapeutic marker in patients who are inclined to thrombotic events after cesarean section.     

Relationship between placental grade and mean platelet volume

Abstract

This study was performed to investigate the correlation between mean platelet volume, as an indicator of thrombocyte function, and placental grade classified by the Grannum scoring system. Placental sonographic images were graded according to the Grannum scoring system, and synchronous haemogram samples were taken from patients who attended foetal assessments during the second and third trimesters. A total of 75 patients were in their second trimester, and 40 patients were in their third trimester. The relation between week of pregnancy and placental Grannum score was significant (p?<?0.001); i.e. placental Grannum score increased with gestational age. The association between Grannum score and mean platelet volume was analysed, including trimester and mean platelet volume, by linear regression analysis. The results indicated a distinct trimester-independent correlation between mean platelet volume and Grannum score (partial correlation coefficient?=?0.455; p?<?0.001). However, no correlation was observed between Grannum score and gravity (r?=?0.87; p?=?0.356), parity (r?=?0.97; p?=?0.302) or abortion (r?=?0.011; p?=?0.91). The correlation between mean platelet volume and placental calcification was investigated, and mean platelet volume in patients with a calcified placenta was 8.23?±?1.14, whereas mean platelet volume in placentas with no calcification was 7.92?±?1.18 (p?=?0.233). Mean platelet volume was an independent indicator of Grannum score, which is an indicator of placental grade, in women in the second and third trimester of pregnancy. Assessing mean platelet volume during routine screening may identify functional placental disorders.     

Mean platelet volume as an inflammatory marker in patients with severe periodontitis

Periodontitis has become the leading cause of tooth loss in adults, and the host’s immunologic and inflammatory response to the bacteria can lead to periodontal destruction. In patients with periodontitis, platelets possess an increased activation status compared with platelets from healthy controls. Mean platelet volume (MPV) has been considered an important index of platelet activity and an inflammatory marker in many infectious diseases. The present study investigated the relationship between MPV and disease activity in subjects with severe periodontitis. Forty-five patients with periodontitis and 45 age and sex-matched healthy subjects were enrolled into the study. All subjects received periodontal and hematological examinations. The periodontitis patients were administered active periodontal treatment (APT). At baseline, a statistically significant decrease in MPV was noted in patients with periodontitis (9.73?±?1.06 fL) compared with healthy controls (10.24?±?1.07 fL). At 1 month post-APT, MPV was substantially increased (10.11?±?1.04 fL). Positive correlation was found between increase of MPV and decrease of periodontal probing depth after treatment(r?=?0.377; p?=?0.014). In conclusion, the decrease of MPV was related to the severe periodontal inflammation, and the value inversed shift after APT. MPV might reflect the disease activity of periodontitis.     

血小板平均体积在支气管哮喘急性发作期的变化

目的观察血小板平均体积(MPV)在支气管哮喘急性发作期患者血清中的变化,探讨血小板平均体积与支气管哮喘急性发作期的关系。方法支气管哮喘急性发作期患者40例,支气管哮喘慢性持续期患者40例,健康对照组40例,分别检测三组血清中血小板平均体积,采用单因素方差分析,比较三组之间血小板平均体积的变化。结果支气管哮喘急性发作期患者血小板平均体积为(10.69±0.96)fl,支气管哮喘慢性持续期为(10.59±0.75)fl,健康对照组为(10.46±0.66)fl,三组两两比较均P0.05,差别有统计学意义。结论支气管哮喘急性发作期患者血清中血小板平均体积较慢性持续期和健康对照组明显升高,可能与支气管哮喘急性发作期的发病及严重程度有关。     

The effect of weight loss on the mean platelet volume in obese patients

Obesity is a chronic metabolic disorder associated with cardiovascular disease and atherosclerosis. Platelet activation and aggregation are central processes in the pathophysiology of cardiovascular disease. Mean platelet volume (MPV), a determinant of platelet activation, is a newly emerging risk marker for atherothrombosis. Our objective was to evaluate the effect of weight loss on the MPV in obese patients. We selected 30 obese women patients and 30 non-obese healthy women subjects. All obese patients took the same content and caloric diet treatment for 3 months. Body mass index (BMI), metabolic parameters and MPV were measured at baseline and after 3 months diet treatment. Before diet treatment, obese group had significantly higher MPV levels than in the non-obese control group (8.18?±?1.09 fl vs. 8.01?±?0.95 fl, p?=?0.004). MPV showed positive correlations with BMI level in the obese group (r?=?0.43, p?=?0.017). BMI significantly decreased after diet treatment (36.2?±?3.2?kg/m² vs. 34.7?±?3.6?kg/m², p?<?0.001), in the obese group. MPV significantly decreased after diet treatment in the obese group (8.18?±?1.09 fl vs. 8.08?±?1.02 fl, p?=?0.013). There was a positive correlation between weight loss and reduction in MPV (r?=?0.41, p?=?0.024). In addition to its well-known positive effects on cardiovascular disease risk, weight loss may also possess significant anti-platelet activation properties that can contribute its antiatherogenic effects in obese patients.     

Platelet count, mean platelet volume and their relation to prognosis in cerebral infarction

The study was performed on patients with ischaemic cerebral infarction in order to obtain information on serial changes of some platelet parameters and to test their prognostic significance. Platelet count, obtained within 48 h after cerebral infarction, was significantly lower than in the control group (213,611 +/- 65,652 mm-3 vs. 299,525 +/- 60,611 mm-3, P less than 0.001), reaching the normal level on the ninth day and thereafter. The mean platelet volume was significantly greater than in the controls (11.26 +/- 1.29 fl vs. 8.93 +/- 0.93 fl, P less than 0.001), and normalization generally occurred on the forty-fifth day. The mean platelet count was significantly lower in the patients who died than in those who survived (P less than 0.025 and P less than 0.05 respectively on the first to second and fourth day after infarction). The reduction of platelet count and the increase of mean volume appear to be related to an increased platelet consumption in the infarction area, associated with an in vivo platelet activation, as larger platelets are more responsive to platelet activity and aggregability tests. The lower mean platelet count observed in the patients who died suggests that the platelet value might be considered as a prognostic index of cerebral infarction.     

Thrombopoietin and mean platelet volume in coronary artery disease

BACKGROUND: Large platelets are shown to be hemostatically more active. It has been suggested that mean platelet volume (MPV) is increased during acute myocardial infarction (AMI) and unstable angina pectoris (USAP). However, the underlying mechanism of the phenomenon remains unclear. HYPOTHESIS: In this study, platelets, MPV, and thrombopoietin (TP) levels were investigated in patients with coronary artery disease (CAD) and healthy controls. METHODS: Twenty patients with AMI and 20 patients with USAP were included in this study. Seventeen healthy adult subjects served as controls. Venous blood samples of the subjects were drawn within 12 h after admission. Thrombopoietin levels were measured by ELISA and platelet counts and MPV were assayed by autoanalyzer. RESULTS: Patients with AMI and USAP had higher platelet counts than those in the control group. Although the platelet counts were slightly higher in AMI than in USAP, this did not reach statistical significance. Mean platelet volume and levels of TP were found to be elevated in patients with AMI and USAP compared with control subjects (p < 0.001). Thrombopoietin levels were higher in AMI than USAP, but this was not statistically significant. There was a positive correlation between TP levels and MPV values (p < 0.05). CONCLUSION: Increased TP levels may increase both platelet counts and platelet size, resulting in hemostatically more active platelets, which may contribute to the development and progression of CAD.     

An overlooked indicator of disease activity in ulcerative colitis: Mean platelet volume

Many non-invasive tests have been studied for diagnosis and determining the activation degree of inflammatory bowel disease (IBD). Nevertheless, an ideal test has not been found yet. Mean platelet volume (MPV) is influenced by the inflammation. In a few study, decreased platelet volume have been reported in IBD. The aim of this study is to determine whether platelet volume would be useful in ulcerative colitis (UC) activity. Additionally we have analyzed overall accuracy of MPV in disease activity and compared with other inflammatory markers. A total of 61 UC patients (male/female : 41/20), and 27 healthy subjects (male/female : 18/9) were enrolled into the study. For all subjects following tests were performed; ESR, CRP, white blood cell count and mean platelet volume. A statistically significant decrease in MPV was noted in patients with UC (8.29 ± 1.02fL) compared with healthy controls (8.65 ± 0.79 fL). MPV of active UC (8.06 ± 1.19 fL) patients were significantly lower than that of inactive UC (8.45 ± 0.87 fL). Overall accuracy of MPV in determination of active UC was 71% (with sensitivity 67%, specificity 73%). A negative correlation was found between MPV and endoscopic activity index (r : -0.358 p : 0.005). In UC, MPV did not correlate with ESR, CRP and white blood cell. Our study showed that MPV reduced in UC, particularly in patients with active UC. Decreased MPV may be an indicator for increased disease activity in patients with UC.