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PloS One 2013Although several studies demonstrated that platelet count is higher in women, decreases with age, and is influenced by genetic background, most clinical laboratories...
BACKGROUND AND OBJECTIVES
Although several studies demonstrated that platelet count is higher in women, decreases with age, and is influenced by genetic background, most clinical laboratories still use the reference interval 150-400×10(9) platelets/L for all subjects. The present study was to identify age- and sex-specific reference intervals for platelet count.
METHODS
We analysed electronic records of subjects enrolled in three population-based studies that investigated inhabitants of seven Italian areas including six geographic isolates. After exclusion of patients with malignancies, liver diseases, or inherited thrombocytopenias, which could affect platelet count, reference intervals were estimated from 40,987 subjects with the non parametric method computing the 2.5° and 97.5° percentiles.
RESULTS
Platelet count was similar in men and women until the age of 14, but subsequently women had steadily more platelets than men. The number of platelets decreases quickly in childhood, stabilizes in adulthood, and further decreases in oldness. The final result of this phenomenon is that platelet count in old age was reduced by 35% in men and by 25% in women compared with early infancy. Based on these findings, we estimated reference intervals for platelet count ×10(9)/L in children (176-452), adult men (141-362), adult women (156-405), old men (122-350) and, old women (140-379). Moreover, we calculated an "extended" reference interval that takes into account the differences in platelet count observed in different geographic areas.
CONCLUSIONS
The age-, sex-, and origin-related variability of platelet count is very wide, and the patient-adapted reference intervals we propose change the thresholds for diagnosing both thrombocytopenia and thrombocytosis in Italy.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Blood Platelets; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Italy; Male; Middle Aged; Platelet Count; Reference Values; Sex Factors; Thrombocytopenia; Thrombocytosis; White People
PubMed: 23382888
DOI: 10.1371/journal.pone.0054289 -
Brazilian Journal of Cardiovascular... Apr 2020Ascending thoracic aortic aneurysm (ATAA), seen in adults, is an important cause of morbidity and mortality. In this study, we aimed to evaluate the levels of mean...
Mean Platelet Volume-to-Platelet Count Ratio, Mean Platelet Volume-to-Lymphocyte Ratio, and Red Blood Cell Distribution Width-Platelet Count Ratio as Markers of Inflammation in Patients with Ascending Thoracic Aortic Aneurysm.
OBJECTIVE
Ascending thoracic aortic aneurysm (ATAA), seen in adults, is an important cause of morbidity and mortality. In this study, we aimed to evaluate the levels of mean platelet volume (MPV), mean platelet volume-to-platelet count ratio (MPVPCR), mean platelet volume-to-lymphocyte ratio (MPVLR), and red cell distribution width platelet count ratio (RDWPCR) in patients with thoracic aortic aneurysm.
METHODS
105 patients admitted to the emergency department were diagnosed with thoracic aortic aneurysm between January and December 2014, and 100 healthy individuals were involved in this retrospective study. MPV, MPVLR, MPVPCR and RDWPCRs were calculated at the time of admission.
RESULTS
Platelet and lymphocyte levels were found to be significantly lower in the patient group when compared to the healthy group (P<0.001, P<0.001, respectively), while MPV, MPVPCR, MPVLR and RDWPCR were found to be significantly higher (P<0.001, P<0.001, P<0.001, and P=0.013, respectively). In the patient group, the high-sensitivity C-reactive protein was significantly higher (P<0.001), and the neutrophil (P=0.062) was also higher. In ROC analysis, MPVPCR had the highest sensitivity (80%) and RDWPCR had the highest specificity (72%).
CONCLUSION
The results for MPV, MPVPCR, MPVLR and RDWPCR can be evaluated as useful parameters in the emergency clinical approach in the evaluation of inflammatory activity in ATAA patients. More extensive studies are required to address the role of these parameters in determining the severity of the disease.
Topics: Aged; Aged, 80 and over; Aortic Aneurysm, Thoracic; Biomarkers; Erythrocyte Indices; Erythrocytes; Female; Humans; Inflammation; Lymphocytes; Male; Mean Platelet Volume; Platelet Count; Retrospective Studies
PubMed: 32369297
DOI: 10.21470/1678-9741-2019-0348 -
Clinical Hemorheology and... 2021Turbulent blood flow in patients with aortic valve stenosis (AS) results in morphological and functional changes in platelets and coagulation factors. The aim of this...
BACKGROUND AND OBJECTIVE
Turbulent blood flow in patients with aortic valve stenosis (AS) results in morphological and functional changes in platelets and coagulation factors. The aim of this study is to determine how shear stress affects platelets and coagulation factors.
METHODS
We retrospectively evaluated data from 78 patients who underwent AVR to treat AS between March 2008 and July 2017 at Kagoshima University Hospital.
RESULTS
Platelet (PLT) count obviously decreased at three days after AVR, and increased above preoperative levels at the time of discharge. In contrast, platelet distribution width (PDW), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) increased three days after AVR, then decreased to below preoperative levels. No differences were evident between groups with higher (HPPG > 100 mmHg) and lower (LPPG < 100 mmHg) peak pressure gradients (PPG) before AVR, whereas PLT count, PDW, MPV and P-LCR improved more in the HPPG group. Plateletcrit (PCT), which represents the total volume of platelets, increased after AVR due to decreased shear stress. High increasing rate of PCT was associated with lower PLT count, higher PDW and lower fibrinogen.
CONCLUSION
Shear stress affects PLT count, PDW, and fibrinogen in patients with AS.
Topics: Aged; Animals; Aortic Valve Stenosis; Blood Platelets; Female; Humans; Male; Mice; Platelet Count; Retrospective Studies
PubMed: 32924997
DOI: 10.3233/CH-200928 -
Biochemia Medica Jun 2022Point-of-care (POC) platelet function tests are faster and easier to perform than in-depth assessment by flow cytometry. At low platelet counts, however, POC tests are...
INTRODUCTION
Point-of-care (POC) platelet function tests are faster and easier to perform than in-depth assessment by flow cytometry. At low platelet counts, however, POC tests are prone to assess platelet function incorrectly. Lower limits of platelet count required to obtain valid test results were defined and a testing method to facilitate comparability between different tests was established.
MATERIALS AND METHODS
We assessed platelet function in whole blood samples of healthy volunteers at decreasing platelet counts (> 100, 80-100, 50-80, 30-50 and < 30 x10/L) using two POC tests: impedance aggregometry and bleeding time. Flow cytometry served as the gold standard. The number of platelets needed to reach 50% of the maximum function (ED) and the lower reference limit (ED) were calculated to define limits of test validity.
RESULTS
The minimal platelet count required for reliable test results was 100 x10/L for impedance aggregometry and bleeding time but only 30 x10/L for flow cytometry. Comparison of ED and ED showed significantly lower values for flow cytometry than either POC test (P value < 0.05) but no difference between POC tests nor between the used platelet agonists within a test method.
CONCLUSION
Calculating the ED and ED provides an effective way to compare values from different platelet function assays. Flow cytometry enables correct platelet function testing as long as platelet count is > 30 x10/L whereas impedance aggregometry and bleeding time are inconsistent unless platelet count is > 100 x10/L.
Topics: Blood Platelets; Flow Cytometry; Humans; Platelet Aggregation; Platelet Count; Platelet Function Tests; Point-of-Care Systems; Thrombocytopenia
PubMed: 35799989
DOI: 10.11613/BM.2022.020713 -
Journal of Clinical Laboratory Analysis Jul 2023Immature platelets (IP) are the youngest circulating platelets, released from megakaryocytes, and demonstrating increased dimensions, significant RNA content, and...
BACKGROUND
Immature platelets (IP) are the youngest circulating platelets, released from megakaryocytes, and demonstrating increased dimensions, significant RNA content, and enhanced activity. Immature platelet research focuses on a differential diagnostic help in patients with thrombocytopenia. The objectives of this study were to compare the variability of IP in citrate and EDTA samples, and to determine stability over time.
METHODS
Fifty-six patients were included for comparison between EDTA and citrate whole blood sample collection. Among the patients, 28 had thrombocytopenia (platelet count < 150G/L). Platelet measurement impedancemetry and fluorimetry were performed with Sysmex XN-9000. The immature platelet fraction (IPF) and absolute immature platelet count (A-IPC) were determined with a fluorescent method.
RESULTS
The mean value of platelet count with fluorescence was, in EDTA sample, 215 ± 171 and, in citrate sample, 153 ± 118 G/L. No significant difference was observed between IPF between EDTA and citrate (7.74 ± 6.68% vs. 8.45 ± 7.37%, p = 0.69), respectively. With the Bland-Altman analysis, the mean difference in the EDTA sample, between 1 and 24 h, was 8.06 ± 6.96% and 8.73 ± 7.12% for IPF, whereas in the citrate sample, between 1 and 6 h, it was 8.60 ± 7.29% and 7.54 ± 6.97%, for IPF. Comparing 1 h EDTA sample with 6 h citrate sample, the variance ratio was 0.974 (95% CI: 0.864-1.084) in IPF.
CONCLUSIONS
We confirmed the potential to conduct IP measurements up to 24 h in the EDTA sample and IPF measurements in the citrate sample for up to 6 h. These results may be useful for the use of IPF, which is a promising parameter whose interest in clinical practice and standardization is not yet well defined.
Topics: Humans; Blood Platelets; Edetic Acid; Platelet Count; Thrombocytopenia; Citric Acid; Citrates
PubMed: 37475131
DOI: 10.1002/jcla.24946 -
Acta Orthopaedica Et Traumatologica... Jul 2023The aim of this study was to present an analysis of platelet-rich plasma obtained from patients with knee osteoarthritis and reveal the factors affecting its features.
OBJECTIVE
The aim of this study was to present an analysis of platelet-rich plasma obtained from patients with knee osteoarthritis and reveal the factors affecting its features.
METHODS
A total of 62 patients (mean age: 56.68 ± 7.13 years) with symptomatic knee osteoarthritis were included in this study. Age (years), gender, height (m), weight (kg), body mass index (kg/m2), duration of symptoms, smoking status, smoking index, general health status, and physical activity scores were recorded. Whole blood and platelet-rich plasma cell counts were performed with a hematology analyzer. White blood cell, red blood cell, and platelet counts were recorded. According to the dose of injected platelets, efficiency of the procedure, purity of platelet-rich plasma, and activation classification, dose of platelets, efficiency of the procedure (platelet recovery rate, %), and purity of the obtained platelet-rich plasma product (relative composition in platelets, %) were calculated. Correlation analysis between the features of platelet-rich plasma and the patient-related variables, including age, gender, body mass index, smoking status, smoking index, presence of other health conditions, physical activity scores, duration of symptoms, and pain levels, was performed.
RESULTS
Dose of injected platelets, efficiency of the procedure, purity of platelet-rich plasma, and activation analysis showed that the dose of injected platelets was 3.25 billion, the efficiency of the process was 77%, and the purity rate of the platelet-rich plasma was 98.4%. Platelet-rich plasma platelet count was correlated with whole blood platelet count (r = 0.81, P < .001), whole blood white blood cell count (r = 0.39, P = .002), smoking status (r = 0.56, P = .03), smoking index (r = -0.63, P = .002), and the presence of hypertension (r = -0.31, P=.04). Platelet-rich plasma white blood cell and purity of platelet-rich plasma were correlated with the smoking status of the patients (r = 0.52, P = .01; r = 0.64, P = .003, respectively).
CONCLUSION
This study has demonstrated that high dose and very pure platelet-rich plasma with medium efficiency was yielded with this platelet-rich plasma preparation procedure; whole blood platelet count, the presence of hypertension, and the smoking status of patients affect the features of the obtained platelet-rich plasma.
LEVEL OF EVIDENCE
Level IV, Diagnostic Study.
Topics: Humans; Middle Aged; Osteoarthritis, Knee; Platelet Count; Body Mass Index; Hypertension
PubMed: 37670448
DOI: 10.5152/j.aott.2023.22077 -
Pediatrics Jul 2018Incidental isolated mild to moderate thrombocytopenia is a frequent laboratory finding prompting a referral to pediatric hematology-oncology. We tested the hypothesis...
OBJECTIVES
Incidental isolated mild to moderate thrombocytopenia is a frequent laboratory finding prompting a referral to pediatric hematology-oncology. We tested the hypothesis that patients with isolated asymptomatic mild thrombocytopenia would not progress to require an intervention from a pediatric hematologist-oncologist.
METHODS
This is a 5-year retrospective review of 113 patients referred to pediatric hematology-oncology for isolated thrombocytopenia. Initial, lowest, and current platelet counts along with clinical course and need for interventions were recorded. Thrombocytopenia was categorized as mild (platelet count: 101-140 × 10/μL), moderate (platelet count: 51-100 × 10/μL), severe (platelet count: 21-50 × 10/μL), and very severe (platelet count: ≤20 × 10/μL).
RESULTS
Eight of 48 patients (17%) referred for initial mild isolated thrombocytopenia progressed to moderate thrombocytopenia at 1 visit. At present, 2 of these patients have moderate thrombocytopenia, 17 remain with mild thrombocytopenia, and 29 patients have resolved thrombocytopenia. Nine of 65 patients (14%) referred for moderate thrombocytopenia progressed to severe or very severe thrombocytopenia on 1 occasion. At present, no patients have severe thrombocytopenia, 18 remain with moderate thrombocytopenia, 14 improved to mild thrombocytopenia, and 33 have resolved thrombocytopenia. Only 3 patients required interventions from a hematologist, whereas 10 patients required therapy from other subspecialties.
CONCLUSIONS
We only identified 3 patients (3%) with mild to moderate thrombocytopenia who required an intervention from a hematologist to improve platelet counts. Patients with isolated mild thrombocytopenia with a normal bleeding history and physical examination findings frequently have normalized their platelet counts within 1 month.
Topics: Asymptomatic Diseases; Child; Disease Progression; Female; Humans; Male; Platelet Count; Prognosis; Referral and Consultation; Retrospective Studies; Risk Factors; Thrombocytopenia
PubMed: 29891565
DOI: 10.1542/peds.2017-3804 -
Journal of Veterinary Diagnostic... Mar 2021In addition to maintaining hemostasis, platelets have an important role in modulating innate and adaptive immune responses. A low platelet count has been found to be a...
In addition to maintaining hemostasis, platelets have an important role in modulating innate and adaptive immune responses. A low platelet count has been found to be a negative prognostic factor for survival in humans and horses with critical illnesses, such as sepsis or systemic inflammatory response syndrome (SIRS). Decreased platelet aggregation, caused by in vivo activation, has been found in human patients with severe sepsis. In our prospective controlled study, we assessed platelet biology in blood samples from 20 equine SIRS cases and 120 healthy control horses. Platelet variables such as platelet count, large platelet count, clumps, plateletcrit, mean platelet volume, and mean platelet component concentration were analyzed by laser flow cytometry (Advia 2120) from KEDTA blood and from citrate blood. Hirudin blood samples were analyzed by impedance aggregometry (Multiplate analyzer; Roche) for platelet aggregation, including spontaneous aggregation and aggregation by 4 different agonists: adenosine diphosphate (ADPtest), ADP + prostaglandin E1 (ADPtestHS), arachidonic acid (ASPItest), and collagen (COLtest). SIRS cases had significantly lower platelet counts in KEDTA blood ( < 0.0001) compared to control horses. There were no significant differences in aggregation values between SIRS cases and controls. Non-surviving SIRS horses did not have statistically significant lower platelet counts or lower aggregation values for COLtest, ADPtest, or ADPtestHS compared to surviving SIRS horses, although 5 non-survivors were thrombocytopenic.
Topics: Animals; Blood Platelets; Case-Control Studies; Female; Germany; Horse Diseases; Horses; Male; Platelet Aggregation; Platelet Count; Prospective Studies; Systemic Inflammatory Response Syndrome
PubMed: 33353486
DOI: 10.1177/1040638720983791 -
Clinical Hemorheology and... 2018Cardiac surgery with cardiopulmonary bypass is associated with important changes in the microcirculation, usually attributed to endothelial dysfunction. Another common...
BACKGROUND
Cardiac surgery with cardiopulmonary bypass is associated with important changes in the microcirculation, usually attributed to endothelial dysfunction. Another common finding of cardiac surgery is postoperative thrombocytopenia and platelet loss of function.
OBJECTIVE
To investigate the association between microvascular flow pattern and postoperative changes in platelet count and function in cardiac surgery patients.
METHODS
Twelve adult cardiac surgery patients received microvascular circulation (sidestream darkfield sublingual mucosa analysis) and platelet count and function (multiple electrode aggregometry ADPtest and TRAPtest) assessment before and after cardiopulmonary bypass.
RESULTS
After cardiopulmonary bypass, sublingual microcirculation showed a significantly (P = 0.001) decreased microvascular flow index and increased heterogeneity index (P = 0.006). Platelet function significantly decrease after cardiopulmonary bypass both at ADPtest (P = 0.011) and TRAPtest (P = 0.002). Preoperative patterns of poor microvascular perfusion (low perfused vessels density and total vessels density) were significantly associated with lower values of post-cardiopulmonary bypass platelet function (ADPtest, P = 0.009, TRAPtest, P = 0.031) and count (P = 0.048).
CONCLUSIONS
A preoperative disturbance of the microcirculation is associated with a greater postoperative platelet dysfunction. Endothelial damage, chemical and mechanical stimuli are the possible link between the two patterns.
Topics: Aged; Blood Platelets; Cardiac Surgical Procedures; Cardiopulmonary Bypass; Cohort Studies; Female; Humans; Male; Microcirculation; Middle Aged; Platelet Count; Platelet Function Tests; Postoperative Period; Prospective Studies
PubMed: 29710690
DOI: 10.3233/CH-180391 -
BioMed Research International 2018Recent study shows that blood-derived amyloid-beta (A) can induce cerebral amyloidosis and is involved in the pathogenesis of Alzheimer's disease (AD). The vast majority...
PURPOSE
Recent study shows that blood-derived amyloid-beta (A) can induce cerebral amyloidosis and is involved in the pathogenesis of Alzheimer's disease (AD). The vast majority of blood A is generated from platelet. Whether blood A levels are associated with the count of platelets remains unknown.
METHODS
58 clinically diagnosed AD patients, 18 C-PIB-PET diagnosed AD patients, and 61 age- and gender-matched cognitively normal controls were included to analyze the correlation of plasma A levels with platelet count. 13 AD patients and 40 controls with cerebrospinal fluid (CSF) samples were included to further analyze the correlation of CSF A levels with platelet count. A40 and A42 levels in plasma and CSF were measured by ELISA kits.
RESULTS
The plasma A42 level was positively correlated with platelet count in both AD patients and control group, especially in AD patients with positive PIB-PET, while there was no correlation as to A40. The CSF A levels also had no significant correlation with platelet count.
CONCLUSION
It suggests that platelets may be involved in the pathogenesis of AD and become a potential peripheral biomarker for AD.
Topics: Aged; Alzheimer Disease; Amyloid beta-Peptides; Biomarkers; Female; Humans; Male; Platelet Count; Positron-Emission Tomography
PubMed: 30410937
DOI: 10.1155/2018/7302045