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American Journal of Clinical Pathology Nov 2016Magnesium sulfate (MgSO 4 ) was recently reported as an alternative in vitro anticoagulant in pseudo-thrombocytopenia. Its suitability as an anticoagulant for the... (Comparative Study)
Comparative Study
OBJECTIVES
Magnesium sulfate (MgSO 4 ) was recently reported as an alternative in vitro anticoagulant in pseudo-thrombocytopenia. Its suitability as an anticoagulant for the determination of reliable platelet parameters is the subject of this study.
METHODS
Platelet count and mean platelet volume were measured in blood samples anticoagulated with EDTA and MgSO 4 and compared. The platelet parameters were determined by impedance (XE 5000 [Sysmex, Norderstedt, Germany]; DxH 800 [Beckman-Coulter, Krefeld, Germany]) and laser light-scatter technology (Advia 120 [Siemens Healthcare Diagnostics, Eschborn, Germany]).
RESULTS
MgSO 4 anticoagulation underestimated platelet counts compared with EDTA. Mean platelet volume (MPV) in magnesium-anticoagulated blood was lower when measured by impedance but higher when light-scatter technology was used. Storage of the differently anticoagulated blood led to differently lower platelet counts after 24 hours, independent of the anticoagulant. In EDTA blood, the mean platelet volume increased moderately when measured by impedance but markedly when measured by laser light scatter. In MgSO 4 -anticoagulated blood, the MPV increase was negligible.
CONCLUSIONS
Impedance technology and magnesium anticoagulation might be advantageous for standardizing MPV measurements, although the mean platelet count is slightly underestimated by both technologies.
Topics: Anticoagulants; Blood Coagulation; Blood Platelets; Electric Impedance; Humans; Magnesium Sulfate; Mean Platelet Volume; Platelet Count; Thrombocytopenia
PubMed: 28430955
DOI: 10.1093/ajcp/aqw146 -
American Journal of Clinical Pathology Jun 2016There are conflicting reports on the reliable measurement of platelet count and mean platelet volume (MPV) using EDTA or citrate. The anticoagulant properties of...
OBJECTIVES
There are conflicting reports on the reliable measurement of platelet count and mean platelet volume (MPV) using EDTA or citrate. The anticoagulant properties of magnesium sulfate (MgSO4) are known from the literature. The aim of this study was to evaluate MgSO4 as an in vitro anticoagulant for platelet count, MPV, platelet distribution width, and platelet activation.
METHODS
Whole blood from volunteers was anticoagulated by EDTA, citrate, or MgSO4 Platelets were counted by the XE 5000 (Sysmex, Norderstedt, Germany) impedance and fluorescence optical technique.
RESULTS
The mean impedance platelet counts were 227.7, 197.0, and 201.1 × 10(9)/L in EDTA-, citrate-, or MgSO4-anticoagulated blood, respectively. The counts were 4.7% higher (EDTA) after 3 hours of storage but 4% lower in citrate-anticoagulated blood. The counts in magnesium samples remained stable. The MPV was 10.4 fL (EDTA), 9.5 fL (citrate), and 9.3 fL (MgSO4). EDTA samples showed cell swelling within the first 3 hours. This was lower in citrate and only marginal in magnesium samples. High activation of platelets was observed only in EDTA samples.
CONCLUSIONS
Magnesium anticoagulation might be advantageous for more reliable MPV measurements. Although platelet count is underestimated when the impedance method is used, the platelet count reveals similar results when measured by the fluorescent optical method.
Topics: Adult; Aged; Aged, 80 and over; Anticoagulants; Blood Platelets; Female; Humans; In Vitro Techniques; Magnesium Sulfate; Male; Middle Aged; Platelet Count; Young Adult
PubMed: 27282617
DOI: 10.1093/ajcp/aqw066 -
Transfusion and Apheresis Science :... Dec 2013Blood bank regulatory agencies including the Drug and Cosmetics Act (DCA) of India do not mandate a predonation platelet count in whole blood donation. Mandating such...
Blood bank regulatory agencies including the Drug and Cosmetics Act (DCA) of India do not mandate a predonation platelet count in whole blood donation. Mandating such practice will definitely optimize the quality of random donor platelets (RDP) in terms of platelet yield and patient therapeutic benefit. We observed poor platelet yield in RDP concentrates prepared at our center with a significant number not meeting the DCA guideline of ≥ 4.5 × 10(10) per bag processed from 450 ml of whole blood. Therefore we planned this study to evaluate the pre-donation hematological values in our blood donor population and effect of these values on the quality of platelet concentrates. The prospective study included 221 blood donors eligible for donating 450 ml of whole blood (WB). Following the departmental standard operating procedure (SOP) RDPs were prepared using the 'Top & Bottom' quadruple bag system and automated component extractor. Quality of RDP was assessed as per departmental protocol. All results were recorded and subsequently transcribed to SPSS working sheet. A significant (p<0.001) decrement of donor blood counts has been observed after WB donation. Mean donor Hb and platelets reduced by 0.72 g/dl and 22.1 × 10(6)/ml respectively. Quality of RDPs in terms of platelet yield was significantly better (p<0.001) when donor platelet count was >200 × 10(6)/ml. Although platelet yield significantly correlated with the donor platelet count however quality of RDPs in terms of red cell contamination showed no correlation with the donor hematocrit. Platelet yield in random donor platelets is a concern in Eastern India. A platelet yield of 4.5 × 10(10) per bag as mandated by the DCA of India was only achieved when the donor platelet count was >200 × 10(6)/ml. Posttransfusion platelet recovery (PPR) was unsatisfactory in the transfused patient. Introduction of pre-donation platelet count in whole blood donation will maximize donor safety and optimize patient platelet transfusion management.
Topics: Adult; Blood Donors; Blood Platelets; Female; Humans; Male; Middle Aged; Platelet Count; Prospective Studies; Young Adult
PubMed: 23928130
DOI: 10.1016/j.transci.2013.07.007 -
Anesthesia and Analgesia Oct 2015The viscoelastic properties of blood clot have been studied most commonly using thrombelastography (TEG) and thromboelastometry (ROTEM). ROTEM-based bleeding treatment... (Review)
Review
The viscoelastic properties of blood clot have been studied most commonly using thrombelastography (TEG) and thromboelastometry (ROTEM). ROTEM-based bleeding treatment algorithms recommend administering platelets to patients with low EXTEM clot strength (e.g., clot amplitude at 10 minutes [A10] <40 mm) once clot strength of the ROTEM® fibrin-based test (FIBTEM) is corrected. Algorithms based on TEG typically use a low value of maximum amplitude (e.g., <50 mm) as a trigger for administering platelets. However, this parameter reflects the contributions of various blood components to the clot, including platelets and fibrin/fibrinogen. The platelet component of clot strength may provide a more sensitive indication of platelet deficiency than clot amplitude from a whole blood TEG or ROTEM® assay. The platelet component of the formed clot is derived from the results of TEG/ROTEM® tests performed with and without platelet inhibition. In this article, we review the basis for why this calculation should be based on clot elasticity (e.g., the E parameter with TEG and the CE parameter with ROTEM®) as opposed to clot amplitude (e.g., the A parameter with TEG or ROTEM®). This is because clot elasticity, unlike clot amplitude, reflects the force with which the blood clot resists rotation within the device, and the relationship between clot amplitude (variable X) and clot elasticity (variable Y) is nonlinear. A specific increment of X (ΔX) will be associated with different increments of Y (ΔY), depending on the initial value of X. When calculated correctly, using clot elasticity data, the platelet component of the clot can provide a valuable insight into platelet deficiency in emergency bleeding.
Topics: Blood Coagulation; Blood Platelets; Elasticity; Humans; Platelet Count; Thrombelastography
PubMed: 26378699
DOI: 10.1213/ANE.0000000000000859 -
Veterinary Clinical Pathology Jun 2010The large size of many feline platelets and the high frequency of platelet aggregation often results in falsely low platelet counts in this species. A combination of...
BACKGROUND
The large size of many feline platelets and the high frequency of platelet aggregation often results in falsely low platelet counts in this species. A combination of optical platelet counting to detect even large platelets and the use of prostaglandin E1 (PGE1) to inhibit platelet clumping may increase the accuracy of feline platelet counting.
OBJECTIVE
The objective of this study was to compare platelet counts in feline whole blood samples with and without the addition of PGE1 and using different analytical methods in a clinical setting.
METHODS
Platelet counts were determined in 10 feline patients in a referral veterinary hospital using 2 sample types (EDTA, EDTA with PGE1) and 2 methods of analysis (optical counting [PLT-O] and impedance counting [PLT-I]) on the Sysmex XT 2000 iV analyzer.
RESULTS
All PGE1-PLT-O samples had platelet counts of >200 x 10(9)/L. Mean platelet count using PGE1-PLT-O (410,256+/-178 x 10(9)/L) was significantly higher (P<.03) compared with PGE1-PLT-I (256+/-113 x 10(9)/L), EDTA-PLT-O (238+/-107 x 10(9)/L), and EDTA-PLT-I (142+/-84 x 10(9)/L) methods. Depending on the method, platelet counts in 2 to 7 of 10 cats were <200 x 10(9)/L when PGE1-PLT-O was not used. A slightly increased platelet count in response to treatment of a feline patient with thrombocytopenia would have been missed without use of PGE1-PLT-O.
CONCLUSIONS
Using PLT-O analysis on EDTA samples containing PGE1 provides higher, and therefore likely more accurate, feline platelet counts in a clinical setting.
Topics: Alprostadil; Animals; Autoanalysis; Cat Diseases; Cats; Edetic Acid; Platelet Aggregation; Platelet Count; Thrombocytopenia
PubMed: 20059753
DOI: 10.1111/j.1939-165X.2009.00210.x -
Transfusion and Apheresis Science :... Apr 2018For Australian apheresis platelet donations, in-centre haematology analysers provided the platelet count used to program the platelet collection machines. When the...
BACKGROUND
For Australian apheresis platelet donations, in-centre haematology analysers provided the platelet count used to program the platelet collection machines. When the haematology analysers were not functional, historical platelet counts from previous donations were used. This study aimed to confirm that the routine use of historical platelet counts for programming apheresis collection machines would maintain platelet yields within the donated units and that haematology analysers could be removed.
STUDY DESIGN
A staggered implementation for the routine use of mean historical platelet counts to program apheresis platelet collection machines was conducted. The donors' full blood counts following donation were tested centrally for comparison to the historical mean. The component yields when using on-the-day platelet counts to program platelet collection were compared with those collected using historical platelet counts. For historical platelet counts to be deemed successful, the target was for 90% of the mean historical donor platelet counts to have less than 20% variance from the on-the-day platelet count.
RESULTS
Over 96% of the mean historical platelet counts were within 20% variance of the platelet count on the day of donation. The component yield (platelet count x10 cell/unit) before analyser removal was 273.3 ± 32.0 (n = 2639) and post-removal was 282.8 ± 38.8 (n = 2689).
CONCLUSION
The removal of haematology analysers from donor centres and replacement with mean historical platelet counts was successful in maintaining platelet yields. Replacement of the haematology analysers with historical platelet counts simplified regulatory compliance, reduced staff workload and costs associated with analyser registration.
Topics: Australia; Blood Donors; Female; Humans; Male; Middle Aged; Platelet Count; Platelet Transfusion; Plateletpheresis
PubMed: 29530405
DOI: 10.1016/j.transci.2018.03.001 -
Journal of Clinical Laboratory Analysis Sep 2015Ethylene diamine tetraacetic acid dependent pseudothrombocytopenia (EDTA-PTCP) is a laboratory artifact that may lead to unnecessary evaluation and treatment of...
BACKGROUND
Ethylene diamine tetraacetic acid dependent pseudothrombocytopenia (EDTA-PTCP) is a laboratory artifact that may lead to unnecessary evaluation and treatment of patients. The purpose of this article is to discuss how to identify EDTA-PTCP and correct spurious low platelet counts in clinical laboratories.
METHODS
We use two criteria to screen for platelet aggregation: (1) an abnormal platelet count in EDTA-treated blood from a patient lacking clinical signs of a platelet disorder, and (2) an instrument flag for platelet clumps. EDTA-PTCP was confirmed by microscopic examination for platelet agglutination and by platelet counts that corrected with citrate sample. In addition, the time course of EDTA-PTCP was investigated in samples from 26 patients anticoagulated with EDTA-K2 and sodium citrate. Amikacin (5 mg/ml) was added to tubes with EDTA-K2 or sodium citrate from seven additional cases in order to confirm its dissociative effect on platelet aggregation.
RESULTS
In our laboratory, the overall incidence of EDTA-PTCP was approximately 0.09%; and the duration was between 2 weeks and 6 months. EDTA-PTCP was time-dependent and occurred as early as 10 min after sample collection. Weaker agglutination could also occur in most corresponding citrate-treated samples. The dissociative effect of amikacin on platelet agglutination was case-specific and not concentration-dependent.
CONCLUSIONS
The method of screening for platelet clumping with the help of XE5000 images is convenient. The decline in the platelet count is related to the length of time and the intensity of chelation. Amikacin supplement is not always effective for correcting platelet counts in vitro.
Topics: Artifacts; Diagnostic Errors; Edetic Acid; Humans; Microscopy; Platelet Aggregation; Platelet Count; Thrombocytopenia
PubMed: 25425098
DOI: 10.1002/jcla.21818 -
The Malaysian Journal of Pathology Dec 2022Thrombocytopenia is a common complication in dengue that sometimes necessitates platelet transfusion. Immature platelet fraction (IPF) measures immature platelets that...
INTRODUCTION
Thrombocytopenia is a common complication in dengue that sometimes necessitates platelet transfusion. Immature platelet fraction (IPF) measures immature platelets that indirectly reflect thrombopoiesis and is helpful in predicting platelet recovery.
OBJECTIVES
This study aimed to evaluate the role of IPF% and identify its cut-off value in predicting platelet recovery in dengue patients with thrombocytopenia.
MATERIALS AND METHODS
Serial platelet count and IPF results were obtained from fifty-four confirmed dengue patients with platelet count <50x109 /L. Median peak IPF% and number of patients with platelet recovery were determined. Receiver operating characteristic (ROC) curve is generated to identify the IPF% cut-off value to predict platelet recovery.
RESULTS
Median peak IPF% among dengue patients was 12.15% with 83.3% of them achieving platelet recovery after reaching the peak IPF%. There was a significant difference between median IPF% on day one of admission with peak IPF% among dengue patients. ROC curve analysis showed IFP% of 10.55% can be used to predict platelet recovery with a sensitivity of 69% and a specificity of 67%.
CONCLUSION
IPF% is a reliable and useful parameter in predicting platelet recovery in dengue patients. This would assist the clinician in managing dengue patients especially those with severe thrombocytopenia without giving unnecessary platelet transfusion.
Topics: Humans; Blood Platelets; Thrombocytopenia; Platelet Count; Platelet Transfusion; Dengue
PubMed: 36591717
DOI: No ID Found -
Arquivos de Cirurgia Clinica E... 1952
Topics: Blood Platelets; Humans; Platelet Count
PubMed: 12987333
DOI: No ID Found -
Seminars in Thrombosis and Hemostasis Jun 2001The clinical decision to proceed with prophylactic platelet transfusions is widely based on trigger points for platelet counts being equal to 20, 10, or even 5 x... (Review)
Review
The clinical decision to proceed with prophylactic platelet transfusions is widely based on trigger points for platelet counts being equal to 20, 10, or even 5 x 10(9)/L. But an increasing number of publications show evidence that the conventional automated platelet counting methods are unable to provide consistently accurate results in this lower thrombocytopenic range. These measurement errors are mainly associated with the most commonly used impedance principle; optical methods seem to be more precise. The problems of counting imprecision in the low thrombocytopenic range can be avoided with direct or indirect immunological counting methods using monoclonal antibodies or by time-consuming manual procedures. But how should new counting procedures be evaluated? Which method should be used as the "gold standard" for platelet counting? A way out of this apparent dilemma is the application of a statistical procedure as proposed by Gautschi et al. This mathematical model allows a reference method independent evaluation of new methods by calculation of the limits of detection (LD) and limits of quantification (LQ) based on the imprecision profile of the investigated method. Using this evaluation procedure, it can be shown that immunological automated counting methods can provide reliable, sufficient, and prompt platelet counts, especially in the thrombocytopenic range.
Topics: Antibodies, Monoclonal; Blood Platelets; Evaluation Studies as Topic; Flow Cytometry; Humans; Models, Theoretical; Platelet Count; Sensitivity and Specificity; Thrombocytopenia
PubMed: 11446656
DOI: 10.1055/s-2001-15252