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JPMA. the Journal of the Pakistan... Sep 2021Pseudo thrombocytopenia is the estimation of low platelet counts by a Haematology analyzer despite of shortage in platelets. EDTA-induced pseudo thrombocytopenia,...
Pseudo thrombocytopenia is the estimation of low platelet counts by a Haematology analyzer despite of shortage in platelets. EDTA-induced pseudo thrombocytopenia, commonly seen in clinical practice, occurs mainly due to the anti-platelet antibodies. Pseudo thrombocytopenia is seen in normal healthy individuals and other disorders like cardiovascular, liver, autoimmune diseases and malignancy. We are presenting a case of multi-coagulant resistant dependent thrombocytopenia. The purpose of this letter is to review approaches to pseudo thrombocytopenia. The case has coagulant resistant dependent thrombocytopenia in association with Anasarca and was a known case of cardiomyopathy with severely dilated left atrium, left ventricle and right atrium.
Topics: Autoimmune Diseases; Blood Platelets; Edetic Acid; Humans; Platelet Count; Thrombocytopenia
PubMed: 34580523
DOI: 10.47391/JPMA.03-390 -
Blood Jan 2021Cyclic thrombocytopenia (CTP) is a rare disease, which is characterized by periodic fluctuation of the platelet count. The pathogenesis of CTP is unknown and most likely...
Cyclic thrombocytopenia (CTP) is a rare disease, which is characterized by periodic fluctuation of the platelet count. The pathogenesis of CTP is unknown and most likely heterogeneous. Patients with CTP are almost always misdiagnosed as having primary immune thrombocytopenia (ITP). The interval between ITP and CTP diagnosis can be many years. CTP patients often receive ITP-specific therapies including corticosteroids, thrombopoietin receptor agonists, rituximab, and splenectomy, which are followed by a transient increase in platelet count that is wrongly attributed to treatment effect with inevitable "relapse." CTP can be diagnosed by frequent platelet count monitoring, which reveals a typical pattern of periodic platelet cycling. An early diagnosis of CTP will prevent these patients from being exposed to possibly harmful therapies. The bleeding phenotype is usually mild and consists of mucocutaneous bleeding at the time when the platelet count is at its nadir. Severe bleeding from other sites can occur but is rare. Some patients respond to cyclosporine A or to danazol, but most patients do not respond to any therapy. CTP can be associated with hematological malignancies or disorders of the thyroid gland. Nevertheless, spontaneous remissions can occur, even after many years.
Topics: Blood Platelets; Humans; Platelet Count; Thrombocytopenia
PubMed: 33197928
DOI: 10.1182/blood.2020008218 -
Blood May 2021
Topics: Platelet Count; Platelet Transfusion
PubMed: 33983425
DOI: 10.1182/blood.2021011269 -
Blood Jun 2022The inherited thrombocytopenia syndromes are a group of disorders characterized primarily by quantitative defects in platelet number, though with a variety demonstrating... (Review)
Review
The inherited thrombocytopenia syndromes are a group of disorders characterized primarily by quantitative defects in platelet number, though with a variety demonstrating qualitative defects and/or extrahematopoietic findings. Through collaborative international efforts applying next-generation sequencing approaches, the list of genetic syndromes that cause thrombocytopenia has expanded significantly in recent years, now with over 40 genes implicated. In this review, we focus on what is known about the genetic etiology of inherited thrombocytopenia syndromes and how the field has worked to validate new genetic discoveries. We highlight the important role for the clinician in identifying a germline genetic diagnosis and strategies for identifying novel causes through research-based endeavors.
Topics: Blood Platelets; High-Throughput Nucleotide Sequencing; Humans; Platelet Count; Syndrome; Thrombocytopenia
PubMed: 35167650
DOI: 10.1182/blood.2020009300 -
Arteriosclerosis, Thrombosis, and... May 2022Human platelets differ considerably with regard to their size, RNA content and thrombogenicity. Reticulated platelets (RPs) are young, hyper-reactive platelets that are... (Review)
Review
Human platelets differ considerably with regard to their size, RNA content and thrombogenicity. Reticulated platelets (RPs) are young, hyper-reactive platelets that are newly released from the bone marrow. They are larger and contain more RNA compared to older platelets. In comparison to more mature platelets, they exhibit a significantly higher thrombogenicity and are known to be elevated in patients with an increased platelet turnover such as, diabetics and after acute myocardial infarction. Several studies have shown that RPs correlate with an insufficient antiplatelet response to aspirin and specific P2Y receptor inhibitors. In addition, RPs are promising novel biomarkers for the prediction of adverse cardiovascular events in cardiovascular disease. However, the reason for RPs intrinsic hyper-reactivity and their association with ischemic events is not completely understood and the biology of RPs is still under investigation. We here present a structured review of preclinical and clinical findings concerning the role of RPs in cardiovascular disease.
Topics: Aspirin; Blood Platelets; Cardiovascular Diseases; Humans; Platelet Aggregation Inhibitors; Platelet Count; RNA
PubMed: 35321562
DOI: 10.1161/ATVBAHA.121.316244 -
JAMA Network Open Jan 2022Individuals with cancer often have an elevated platelet count at the time of diagnosis. The extent to which an elevated platelet count is an indicator of cancer is...
IMPORTANCE
Individuals with cancer often have an elevated platelet count at the time of diagnosis. The extent to which an elevated platelet count is an indicator of cancer is unclear.
OBJECTIVE
To evaluate the association of an elevated platelet count with a cancer diagnosis.
DESIGN, SETTING, AND PARTICIPANTS
This nested case-control study included Ontario residents enrolled in the provincial health insurance plan who had 1 or more routine complete blood count (CBC) tests performed between January 1, 2007, and December 31, 2017, with follow-up through December 31, 2018. Case patients were individuals with a new cancer diagnosis during the observation period. Eligible control individuals were cancer free before the date of diagnosis for a case patient to whom they were matched. One case patient was matched to 3 controls based on sex, age, and health care use patterns. Data were analyzed from September 24, 2020, to July 13, 2021.
EXPOSURES
Case patients and controls were assigned to 1 of 5 exposure groups based on age- and sex-specific platelet count distributions in the control population: very low (≤10th percentile), low (>10th to 25th percentile), medium (>25th to <75th percentile), high (75th to <90th percentile), and very high (≥90th percentile).
MAIN OUTCOMES AND MEASURES
Odds ratios (ORs) were estimated for specific cancer sites for each category of platelet count at intervals up to 10 years after a blood test.
RESULTS
Of the 8 917 187 eligible Ontario residents with a routine CBC record available, 4 971 578 (55.8%) were women; the median age at the first CBC was 46.4 years (IQR, 32.5-59.5 years). Among individuals with a routine CBC record available, 495 341 (5.6%) received a diagnosis of first primary cancer during the 10-year observation period. The OR for a solid tumor diagnosis associated with a very high platelet count vs a medium platelet count in the 6-month period before the diagnosis was 2.32 (95% CI, 2.28-2.35). A very high platelet count was associated with colon (OR, 4.38; 95% CI, 4.22-4.54), lung (OR, 4.37; 95% CI, 4.22-4.53), ovarian (OR, 4.62; 95% CI, 4.19-5.09), and stomach (OR, 4.27; 95% CI, 3.91-4.66) cancers. Odds ratios attenuated with increasing time from CBC test to cancer diagnosis.
CONCLUSIONS AND RELEVANCE
In this nested case-control study, an elevated platelet count was associated with increased risk of cancer at several sites. Our findings suggest that an elevated platelet count could potentially serve as a marker for the presence of some cancer types.
Topics: Adult; Biomarkers; Case-Control Studies; Female; Humans; Male; Middle Aged; Neoplasms; Ontario; Platelet Count
PubMed: 35015064
DOI: 10.1001/jamanetworkopen.2021.41633 -
Medicine Nov 2023The objective of this study was to ascertain the potential causal linkage between platelet (PLT) counts and the incidence of gastric cancer (GC). This study employed a...
The objective of this study was to ascertain the potential causal linkage between platelet (PLT) counts and the incidence of gastric cancer (GC). This study employed a 2-sample Mendelian randomization (MR) approach, utilizing the inverse variance weighting, weighted median, and MR-Egger regression methodologies. The publicly accessible summary statistics dataset from the genome-wide association study pertaining to individuals of European ancestry (n = 145,648) was employed as the foundational resource for the exposure variable. Concomitantly, the non-cancer disease codes for GC (n = 6563), derived from individuals within the UK Biosample Bank, were utilized as the outcome measure. A set of 132 single-nucleotide polymorphisms exhibiting genome-wide significance were selected as instrumental variables, drawn from the genome-wide association studies focused on PLT counts. The application of the weighted median methodology yielded indications suggesting the possible absence of a causal relationship between PLT counts and GC (beta = 0.139, SE = 0.079, P = .077). Contrarily, the implementation of the inverse variance weighting technique produced results indicative of a potential causal relationship between PLT counts and GC (beta = 0.128, SE = 0.049, P = .009). The assessment of Cochran Q test and the scrutiny of funnel plots unveiled no discernible indications of heterogeneity or asymmetry, thus signifying the absence of directional pleiotropy. The outcomes derived from the MR analysis lend credence to the hypothesis that there exists a plausible causal relationship between erythrocyte pressure and an elevated susceptibility to gastric cancer.
Topics: Humans; Genome-Wide Association Study; Mendelian Randomization Analysis; Platelet Count; Stomach Neoplasms; Causality; Polymorphism, Single Nucleotide
PubMed: 37933067
DOI: 10.1097/MD.0000000000035790 -
Thrombosis Research Mar 2023Platelets are primarily recognized for their role in hemostasis, but also regulate immune responses by interacting with leukocytes. Their highly sensitive nature enables...
Platelets are primarily recognized for their role in hemostasis, but also regulate immune responses by interacting with leukocytes. Their highly sensitive nature enables platelets to rapidly respond to micro-environmental changes, which is crucial under physiological condition but can jeopardize in vitro analyses. Thus, we tested how platelet count and changes in pH and temperatures, which are commonly experienced during inflammation and infection but also affected by ex vivo analyses, influence platelet-leukocyte interaction and immunomodulation. Reducing platelet count by up to 90 % slightly decreased platelet activation and platelet-leukocyte aggregate formation, but did not affect CD11b activation nor CD62L shedding of monocytes or neutrophils. Acidosis (pH 6.9) slightly elevated platelet degranulation and binding to innate leukocytes, though pH changes did not modulate leukocyte activation. While platelet responsiveness was higher at room temperature than at 37 °C, incubation temperature did not affect platelet-leukocyte aggregate formation. In contrast, platelet-mediated CD11b activation and CD62L expression increased with temperature. Our data thus demonstrate the importance of standardized protocols for sample preparation and assay procedure to obtain comparable data. Further, unspecific physiologic responses such as thrombocytopenia, acidosis or temperature changes may contribute to platelet dysfunction and altered platelet-mediated immunomodulation in inflammatory and infectious disease.
Topics: Humans; Temperature; Platelet Count; Hemostatics; Blood Platelets; Platelet Activation; Hemostasis; Leukocytes; Immunity; Acidosis; Hydrogen-Ion Concentration
PubMed: 36738664
DOI: 10.1016/j.thromres.2023.01.026 -
Platelets Apr 2021Platelets are damage sentinels of the intravascular compartment, initiating and coordinating the primary response to tissue injury. Severe trauma and hemorrhage induce... (Review)
Review
Platelets are damage sentinels of the intravascular compartment, initiating and coordinating the primary response to tissue injury. Severe trauma and hemorrhage induce profound alterations in platelet behavior. During the acute post-injury phase, platelets develop a state of impaired agonist responsiveness independent of platelet count, associated with systemic coagulopathy and mortality risk. In patients surviving the initial insult, platelets become hyper-responsive, associated with increased risk of thrombotic events. Beyond coagulation, platelets constitute part of a sterile inflammatory response to injury: both directly through release of immunomodulatory molecules, and indirectly through modifying behavior of innate leukocytes. Both procoagulant and proinflammatory aspects have implications for secondary organ injury and multiple-organ dysfunction syndromes. This review details our current understanding of adaptive and maladaptive alterations in platelet biology induced by severe trauma, mechanisms underlying these alterations, potential platelet-focused therapies, and existing knowledge gaps and their research implications.
Topics: Blood Platelets; Female; Humans; Male; Platelet Count; Wounds and Injuries
PubMed: 31986948
DOI: 10.1080/09537104.2020.1718633 -
Effects of Platelet Count on Blood Pressure: Evidence from Observational and Genetic Investigations.Genes Dec 2023Platelet count has been associated with blood pressure, but whether this association reflects causality remains unclear. To strengthen the evidence, we conducted a...
Platelet count has been associated with blood pressure, but whether this association reflects causality remains unclear. To strengthen the evidence, we conducted a traditional observational analysis in the Lifelines Cohort Study ( = 167,785), and performed bi-directional Mendelian randomization (MR) with summary GWAS data from the UK Biobank ( = 350,475) and the International Consortium of Blood Pressure (ICBP) ( = 299,024). Observational analyses showed positive associations between platelet count and blood pressure (OR = 1.12 per SD, 95% CI: 1.10 to 1.14 for hypertension; B = 0.07, 95% CI: 0.07 to 0.08 for SBP; B = 0.07 per SD, 95% CI: 0.06 to 0.07 for DBP). In MR, a genetically predicted higher platelet count was associated with higher SBP (B = 0.02 per SD, 95% CI = 0.00 to 0.04) and DBP (B = 0.03 per SD, 95% CI = 0.01 to 0.05). IVW models and sensitivity analyses of the association between platelet count and DBP were consistent, but not all sensitivity analyses were statistically significant for the platelet count-SBP relation. Our findings indicate that platelet count has modest but significant effects on SBP and DBP, suggesting causality and providing further insight into the pathophysiology of hypertension.
Topics: Humans; Blood Pressure; Cohort Studies; Platelet Count; Hypertension; UK Biobank
PubMed: 38137055
DOI: 10.3390/genes14122233