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Pediatric Research Feb 2023Small-for-gestational-age (SGA) infants are at increased risk for transient thrombocytopenia. The aim of this study was to determine whether thrombocytopenia in human...
BACKGROUND
Small-for-gestational-age (SGA) infants are at increased risk for transient thrombocytopenia. The aim of this study was to determine whether thrombocytopenia in human SGA infants is due to insufficient thrombopoietin (TPO) production.
METHODS
A prospective study of 202 infants with gestational age less than 37 weeks was conducted; 30 of them were SGA infants, and 172 were non-SGA infants. Thrombocytopenia was seen in 17 of 30 SGA infants and 40 of 172 non-SGA infants.
RESULTS
Platelet counts were significantly lower in the SGA group than in the non-SGA group at the time of the lowest platelet count within 72 h of birth. The platelet count and immature platelet fraction (IPF) were negatively correlated in non-SGA infants, but not in SGA infants. In addition, the platelet count and TPO were negatively correlated in non-SGA infants. IPF and TPO were significantly lower in SGA than in non-SGA infants with thrombocytopenia.
CONCLUSION
IPF increased with thrombocytopenia to promote platelet production in non-SGA infants due to increasing TPO, but not in SGA infants. This study found an association between insufficient TPO production and thrombocytopenia in SGA infants. In addition, this study is important for understanding the etiology of thrombocytopenia in SGA infants.
IMPACT
The immature platelet fraction was low, and serum thrombopoietin was not increased in small-for-gestational-age (SGA) infants with thrombocytopenia. Thrombocytopenia in SGA infants is due to insufficient thrombopoietin production. This study is important for understanding the etiology of thrombocytopenia in SGA infants.
Topics: Female; Humans; Infant; Prospective Studies; Thrombopoietin; Thrombocytopenia; Platelet Count; Blood Platelets; Fetal Growth Retardation
PubMed: 35568734
DOI: 10.1038/s41390-022-02107-7 -
Ginekologia Polska 2021To compare platelet indices in preeclamptic and normotensive pregnants and to investigate the clinical use of these parameters in preeclampsia prediction.
OBJECTIVES
To compare platelet indices in preeclamptic and normotensive pregnants and to investigate the clinical use of these parameters in preeclampsia prediction.
MATERIAL AND METHODS
This retrospective case- control study included 257 preeclampsia patients and 264 healthy pregnant women as the control group. The groups were compared in terms of platelet count (PC), mean platelet volume (MPV), platelet distribution range (PDW), plateletcrit (Pct), Pct / MPV ratio and PC / MPV ratio.
RESULTS
Between the preeclampsia group and the control group; mean platelet count (227.22 ± 78.58 vs 236.69 ± 64.30), plateletcrit (PCT) (0.21 ± 0.06 vs 0.24 ± 0.27), and platelet distribution width (PDW) (17.11 ± 0.80 vs 17.29 ± 0.82) were not significantly different (p> 0.05). However, MPV values were significantly higher in the preclampsia group compared to the control group (9.66 ± 1.62 and 8.92 ± 1.33, respectively) (p < 0.001). In our study, the optimum cut-off value of MPV was 9.15 with 58.7% sensitivity and 61.7% specificity for the prediction of preeclampsia. Pct/MPV ratio (0.02 ± 0.007 vs 0.027 ± 0.029) ( p = 0.01) and PC/MPV ratio ( 24.63 ± 10.90 vs 27.63 ± 10.24) (p = 0.001) were significantly lower in the preeclampsia group than in the control group.
CONSLUSIONS
In preeclampsia, changes in platelet functions, destruction and production lead to changes in platelet indices. Compared with normal healthy pregnant women, preeclamptic pregnant women have higher MPV values. In preeclampsia prediction, MPV and PC/MPV ratio are promising as a diagnostic parameter.
Topics: Blood Platelets; Female; Humans; Mean Platelet Volume; Platelet Count; Pre-Eclampsia; Pregnancy; Retrospective Studies
PubMed: 34105753
DOI: 10.5603/GP.a2021.0056 -
Communications Biology Sep 2021Platelets play an important role in hemostasis and other aspects of vascular biology. We conducted a meta-analysis of platelet count GWAS using data on 536,974 Europeans... (Meta-Analysis)
Meta-Analysis
Platelets play an important role in hemostasis and other aspects of vascular biology. We conducted a meta-analysis of platelet count GWAS using data on 536,974 Europeans and identified 577 independent associations. To search for mechanisms through which these variants affect platelets, we applied cis-expression quantitative trait locus, DEPICT and IPA analyses and assessed genetic sharing between platelet count and various traits using polygenic risk scoring. We found genetic sharing between platelet count and counts of other blood cells (except red blood cells), in addition to several other quantitative traits, including markers of cardiovascular, liver and kidney functions, height, and weight. Platelet count polygenic risk score was predictive of myeloproliferative neoplasms, rheumatoid arthritis, ankylosing spondylitis, hypertension, and benign prostate hyperplasia. Taken together, these results advance understanding of diverse aspects of platelet biology and how they affect biological processes in health and disease.
Topics: Biomarkers; Female; Genetic Variation; Humans; Male; Phenotype; Platelet Count; Quantitative Trait Loci
PubMed: 34580418
DOI: 10.1038/s42003-021-02642-9 -
Blood Advances May 2022Circulating large "preplatelets" undergo fission via barbell platelet intermediates into two smaller, mature platelets. In this study, we determine whether preplatelets...
Circulating large "preplatelets" undergo fission via barbell platelet intermediates into two smaller, mature platelets. In this study, we determine whether preplatelets and/or barbells are equivalent to reticulated/immature platelets by using ImageStream flow cytometry and super-resolution microscopy. Immature platelets, preplatelets, and barbells were quantified in healthy and thrombocytopenic mice, healthy human volunteers, and patients with immune thrombocytopenia or undergoing chemotherapy. Preplatelets and barbells were 1.9% ± 0.18%/1.7% ± 0.48% (n = 6) and 3.3% ± 1.6%/0.5% ± 0.27% (n = 12) of total platelet counts in murine and human whole blood, respectively. Both preplatelets and barbells exhibited high expression of major histocompatibility complex class I with high thiazole orange and Mitotracker fluorescence. Tracking dye experiments confirmed that preplatelets transform into barbells and undergo fission ex vivo to increase platelet counts, with dependence on the cytoskeleton and normal mitochondrial respiration. Samples from antibody-induced thrombocytopenia in mice and patients with immune thrombocytopenia had increased levels of both preplatelets and barbells correlating with immature platelet levels. Furthermore, barbells were absent after chemotherapy in patients. In mice, in vivo biotinylation confirmed that barbells, but not all large platelets, were immature. This study demonstrates that a subpopulation of large platelets are immature preplatelets that can transform into barbells and undergo fission during maturation.
Topics: Animals; Blood Platelets; Flow Cytometry; Humans; Mice; Platelet Count; Purpura, Thrombocytopenic, Idiopathic; Thrombocytopenia
PubMed: 35042240
DOI: 10.1182/bloodadvances.2021006073 -
PloS One 2019Gender influences platelet biology. Women have a larger platelet count, but gender-based differences in platelet function remain debated. We performed a study addressing...
BACKGROUND
Gender influences platelet biology. Women have a larger platelet count, but gender-based differences in platelet function remain debated. We performed a study addressing gender-based differences in platelet function using point-of-care platelet function tests (PFT).
METHODS
The patient population consisted of 760 cardiac surgery patients where preoperative PFT (multiple-electrode aggregometry [MEA]) were available. Platelet count and function at the ADPtest and TRAPtest were compared in the overall population and separately in patients with or without residual effects of P2Y12 inhibitors.
RESULTS
Women had a significantly (P = 0.001) higher platelet count but a non-significantly higher platelet reactivity to ADP. In clopidogrel-treated patients, the platelets ADP reactivity was significantly (P = 0.031) higher in women, and platelet count was the main determinant of platelet hyper-reactivity. Within patients under full clopidogrel effects, women with a platelet count ≥ 200,000 cells/μL had a significantly (P = 0.023) higher rate of high-on-treatment platelet reactivity (HTPR, 45.5%) with respect to males with a platelet count < 200,000 cells/μL (11.9%), with a relative risk of 6.2 (95% confidence interval 1.4-29).
CONCLUSIONS
Our findings confirm that women have a larger platelet count than men, and that this is associated to a trend towards a higher platelet reactivity. HTPR is largely represented in women with a high platelet count. This generates the hypothesis that women requiring P2Y12 inhibitors could potentially benefit from larger doses of drug or should be treated with anti-platelet agents with a low rate of HTPR.
Topics: Adenosine Diphosphate; Aged; Blood Platelets; Cardiac Surgical Procedures; Female; Humans; Male; Middle Aged; Platelet Aggregation; Platelet Count; Platelet Function Tests; Purinergic P2Y Receptor Antagonists; Sex Factors
PubMed: 31774869
DOI: 10.1371/journal.pone.0225771 -
Advances in Clinical and Experimental... Dec 2023Antiplatelet therapy is the cornerstone of treatment for patients presenting with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI)....
BACKGROUND
Antiplatelet therapy is the cornerstone of treatment for patients presenting with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI). Some patients may not respond to such therapy adequately, which is associated with a greater risk of ischemic events. Reticulated platelets are the youngest, largest, and most active platelet subtype. They have been initially shown to be associated with an increased risk of cardiovascular (CV) events and increased platelet activity.
OBJECTIVES
The aim of the presented study was to evaluate whether the immature platelet fraction (IPF) reflects the response to antiplatelet treatment in invasively managed ACS patients.
MATERIAL AND METHODS
This prospective study enrolled ACS patients treated with PCI and dual antiplatelet therapy (DAPT) comprising acetylsalicylic acid (ASA) and clopidogrel or ticagrelor. In all patients, venous blood was collected within 24 h after the procedure. Platelet parameters were measured, including IPF using the Sysmex hematological analyzer and adenosine diphosphate (ADP)-induced platelet reactivity using the Multiplate® Analyzer.
RESULTS
A total of 108 patients were enrolled, including 62 with ST-segment elevation ACS (STE-ACS) and 46 with non-ST-segment elevation ACS (NSTE-ACS). Of them, 20.4% had diabetes mellitus, 26.9% had a history of MI and 59.2% of smoking. Spearman's correlation analysis demonstrated that higher IPF and immature platelet count (IPC) values are associated with increased ADP-induced platelet reactivity (respectively: rho = 0.387, 95% confidence interval (95% CI): 0.101-0.615, p = 0.008; and rho = 0.458, 95% CI: 0.185-0.666, p = 0.001) in NSTE-ACS but not in STE-ACS patients.
CONCLUSION
Immature platelet count and IPF may be valuable markers of platelet activity in patients with NSTE-ACS treated invasively and receiving DAPT (ClinicalTrials.gov No. NCT06177587).
Topics: Humans; Acute Coronary Syndrome; Adenosine; Adenosine Diphosphate; Biomarkers; Percutaneous Coronary Intervention; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Count; Platelet Function Tests; Prospective Studies; Ticlopidine
PubMed: 38126718
DOI: 10.17219/acem/177406 -
Thrombosis Research Mar 2023The bleeding phenotype in immune thrombocytopenia (ITP) is heterogeneous, but usually mild and only partly dependent on the severity of thrombocytopenia. Platelet...
BACKGROUND
The bleeding phenotype in immune thrombocytopenia (ITP) is heterogeneous, but usually mild and only partly dependent on the severity of thrombocytopenia. Platelet reactivity has previously been suggested to underly the mild phenotype.
METHODS
Platelet function was assessed as basal and agonist-induced surface expression of P-selectin and activation of GPIIb/IIIa via flow cytometry, and soluble (s)P-selectin levels were assessed in plasma of 77 patients with primary ITP, 19 hemato-oncologic thrombocytopenic controls (TC) and 20 healthy controls (HC). The association of platelet function with laboratory and clinical parameters such as bleeding manifestations at inclusion and previous thrombosis was analyzed.
RESULTS
ITP patients showed tendency towards increased surface P-selectin and elevated levels of activated GPIIb/IIIa. Platelet activation after stimulation with all agonists including TRAP-6, ADP, arachidonic acid and CRP was decreased compared to HC. Compared to TC, only GPIIb/IIIa activation but not surface P-selectin was higher in ITP. Levels of soluble (s)P-selectin were significantly higher in ITP patients compared to TC, but similar to HC. Higher sP-selectin levels were associated with blood group O and current therapy, with highest levels in TPO-RA treated patients. Platelet reactivity was not associated with platelet count or size, platelet antibodies, treatment regime, or blood group. No correlation between platelet activation with the bleeding phenotype or previous thrombotic events could be observed.
CONCLUSION
ITP patients did not have hyper-reactive platelets compared to HC, but partly higher reactivity compared to TC. Further studies are needed to understand the underlying mechanism behind the bleeding and pro-thrombotic phenotype in ITP. 250/250.
Topics: Humans; Purpura, Thrombocytopenic, Idiopathic; P-Selectin; Blood Platelets; Platelet Count; Thrombocytopenia; Hemorrhage; Platelet Glycoprotein GPIIb-IIIa Complex
PubMed: 36738663
DOI: 10.1016/j.thromres.2023.01.012 -
BMC Pediatrics Dec 2022Severe neonatal thrombocytopenia is a rare disease with multiple etiologies. Severe thrombocytopenia with bleeding is life-threatening and has attracted significant...
BACKGROUND
Severe neonatal thrombocytopenia is a rare disease with multiple etiologies. Severe thrombocytopenia with bleeding is life-threatening and has attracted significant attention from clinicians. However, only a few studies have focused on the association between severe thrombocytopenia and bleeding. Thus, this study aimed to describe the neonates' postnatal age at which severe thrombocytopenia was first recognized, clinical characteristics, bleeding patterns, and outcomes and to evaluate the association between minimum platelet count and bleeding.
METHODS
A single-center retrospective cohort study for neonates with severe thrombocytopenia (platelet count ≤ 50 × 10/L) was conducted. Neonates who were admitted to our neonatal intensive care unit between October 2016 and February 2021 and developed severe thrombocytopenia were analyzed. Data were collected retrospectively until the patients were referred to other hospitals, discharged, or deceased.
RESULTS
Among the 5819 neonatal inpatients, 170 with severe thrombocytopenia were included in this study. More than 30% of the patients had severe thrombocytopenia in the first 3 days of life. Among the 118 neonates with bleeding, 47 had more than one type of pathological bleeding. Neonates with very severe thrombocytopenia (point estimate: 53.7%, 95% confidence interval [CI]: 44.2%-63.1%) had a higher incidence rate of cutaneous bleeding than those with severe thrombocytopenia (point estimate: 23.4%, 95% CI: 12.3%-34.4%). The gestational age (median: 36.2 [interquartile range [IQR]: 31.4-39.0] weeks) and birth weight (median: 2310 [IQR: 1213-3210] g) of the major bleeding group were the lowest among no bleeding, minor bleeding, and major bleeding groups. Regression analysis controlled for confounders and confirmed that a lower platelet count (odds ratio [OR]: 2.504 [95% CI: 1.180-5.314], P = 0.017) was associated with a significant increase in the rate of bleeding. Very severe thrombocytopenia (point estimate: 49.1%, 95% CI: 39.6%-58.6%) had a higher rate of platelet transfusion than severe thrombocytopenia (point estimate: 5.7%, 95% CI: 0.7%-10.7%). The mortality rate was higher in neonates with bleeding than in those without bleeding (point estimates with 95% CI: 33.1% [24.4%-41.7%] vs. 7.7% [0.2%-15.2%]).
CONCLUSIONS
These findings describe the incidence of severe thrombocytopenia and demonstrate that a lower platelet count is associated with an increased bleeding rate in patients with severe thrombocytopenia.
Topics: Infant, Newborn; Humans; Infant; Retrospective Studies; Thrombocytopenia; Hemorrhage; Platelet Count; Platelet Transfusion
PubMed: 36550455
DOI: 10.1186/s12887-022-03802-4 -
Cardiovascular Journal of AfricaPlatelet dysfunction has been shown to play a role in postoperative bleeding, however it is not clear whether immature platelets (IP) can induce appropriate homeostasis...
BACKGROUND
Platelet dysfunction has been shown to play a role in postoperative bleeding, however it is not clear whether immature platelets (IP) can induce appropriate homeostasis to prevent excessive bleeding in patients undergoing coronary artery bypass grafting (CABG). The aim of this study was to evaluate the postoperative change in IP count (IPC), IP fraction (IPF) and mean platelet volume (MPV), and to examine their relationship with postoperative bleeding and blood transfusion.
METHODS
One hundred and forty-nine consecutive patients undergoing elective CABG were included in this prospective study. All CABGs were performed by the same surgical team in a standardised method, utilising the on-pump technique. IPC, MPV and IPF were measured pre-operatively, after the completion of surgery, and at the postoperative first, third and fifth days. The primary outcome measure of this study was whether the need for transfusion was associated with IP, IPF, MPV and platelet count.
RESULTS
There was a significant decrease of 7.77% in IPC on the day of the operation. Pre-operative IPC and IPF were correlated with postoperative drainage ( < 0.001), intraoperative blood transfusion ( < 0.001) and intensive care unit blood transfusion ( < 0.001). Pre-operative haemoglobin levels were significantly correlated with length of hospital stay. However, neither pre-operative IPC nor IPF were associated with length of hospital stay. Postoperative IPC was however associated with the length of hospital and intensive care unit stay ( = 0.008 and = 0.009, respectively).
CONCLUSIONS
Pre-operative IPC and IPF were significantly correlated with postoperative drainage and blood transfusion frequency. In patients undergoing CABG, these can be seen as serious guiding parameters in the estimation of postoperative bleeding.
Topics: Blood Transfusion; Coronary Artery Bypass; Humans; Mean Platelet Volume; Platelet Count; Postoperative Hemorrhage; Prospective Studies
PubMed: 34546284
DOI: 10.5830/CVJA-2021-041 -
Journal of the American Heart... Jul 2023Background We examined whether the relationship between baseline platelet count and clinical outcomes is modulated by HS-CRP (high-sensitivity C-reactive protein) in...
Background We examined whether the relationship between baseline platelet count and clinical outcomes is modulated by HS-CRP (high-sensitivity C-reactive protein) in patients with ischemic stroke. Methods and Results A total of 3267 patients with ischemic stroke were included in the analysis. The primary outcome was a combination of death and major disability at 1 year after ischemic stroke. Secondary outcomes included major disability, death, vascular events, composite outcome of vascular events or death, and an ordered 7-level categorical score of the modified Rankin Scale at 1 year. Multivariate logistic regression and Cox proportional hazards regression models were used to assess the association between the baseline platelet count and clinical outcomes stratified by HS-CRP levels when appropriate. There was an interaction effect of platelet count and HS-CRP on the adverse clinical outcomes after ischemic stroke (all <0.05). The elevated platelet count was significantly associated with the primary outcome (odds ratio [OR], 3.14 [95% CI, 1.77-5.58]), major disability (OR, 2.07 [95% CI, 1.15-3.71]), death (hazard ratio [HR], 2.75 [95% CI, 1.31-5.79]), and composite outcome of vascular events or death (HR, 2.57 [95% CI, 1.38-4.87]) among patients with high HS-CRP levels (all <0.05). Conclusions The HS-CRP levels had a modifying effect on the association between platelet count and clinical outcomes in patients with ischemic stroke. Elevated platelet count was significantly associated with adverse clinical outcomes in patients with ischemic stroke with high HS-CRP levels, but not in those with low HS-CRP levels. These findings suggest that strategies for anti-inflammatory and antiplatelet therapy should be developed according to the results of both platelet and HS-CRP testing.
Topics: Humans; C-Reactive Protein; Prognosis; Biomarkers; Ischemic Stroke; Platelet Count; Stroke; Brain Ischemia
PubMed: 37449575
DOI: 10.1161/JAHA.123.030007