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Results for “Platelet Count”

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PubMed1997

Correlation between serum gamma-glutamyl transferase activity and the platelet count.

The serum gamma-glutamyl transferase (GGT) activity correlated significantly (P < 0.008) with the platelet count in 55 patients with thrombocytosis. All patients were selected so as to have normal liver function tests(including serum GGT). This correlation was present in both genders and there was no significant correlation with the other liver function tests. These findings are additional evidence that platelets may contribute to the total serum GGT activity.

Journal Article↗

PubMed1995

Simple method for platelet counting.

A method is proposed for counting the number of adhered platelets based on the determination of lactate dehydrogenase activity in bulk after lysis of adhered platelets. This method was compared with the widely used radioisotope labelling technique. It was concluded that the present lactate dehydrogenase method is effective in counting the adhered platelets, as no significant difference was found between the readings of two methods when commercial polymers and glass were used as samples.

Biocompatible Materials↗

PubMed1998

Routine maternal platelet count: an assessment of a technologically driven screening practice.

Because automated blood cell counters are now widely used in many clinical settings, an assessment of hemoglobin concentration or hematocrit is invariably accompanied by a platelet count. Thus many asymptomatic pregnant women are being screened for thrombocytopenia. The objective of a good screening program is to reduce morbidity and mortality and thereby improve the quality of life; criteria for the evaluation of proposed or ongoing screening programs are well established. However, the screening of pregnant women for thrombocytopenia seems to have been both technologically mandated and passively accepted. Therefore we systematically evaluated the current de facto screening of asymptomatic pregnant patients for thrombocytopenia in the context of well-explained, desirable characteristics for a successful screening program. We conclude that screening for thrombocytopenia in pregnancy fails to meet established criteria, may actually be harmful (by placing unaffected fetuses of thrombocytopenic women, and the women themselves, at risk from invasive procedures), and should therefore be discontinued.

Cost-Benefit Analysis↗

PubMed1983

The effect of maternal steroid administration on fetal platelet count in immunologic thrombocytopenic purpura. Management of pregnancy and mode of delivery.

Eight pregnancies complicated by immunologic thrombocytopenic purpura are described and the literature is reviewed. We conclude that, while steroid treatment favorably influenced fetal platelet counts in our cases, overall experience with this disease indicates that such protection is incomplete in some cases and unnecessary in others. Antiplatelet antibody levels show promise as excellent indicators of fetal thrombocytopenia, and elevated levels may be an indication for steroid therapy for the improvement of fetal well-being in some cases.

Adrenal Cortex Hormones↗

PubMedDate not supplied

[The importance of aminotransferases and platelets count in non-invasive evaluation stages of chronic hepatitis C].

143 patients with chronic hepatitis C were investigated. The following two parameters were determined: the asparate to alanine aminotransferase ratio and the asparate aminotransferase to platelets count index. A liver biopsy was performed for every patient and stages of liver fibrosis were evaluated. Both parameters confirmed a positive correlation with liver fibrosis, which can be useful in predicting the progression of chronic hepatitis C.

Adult↗

PubMed1978

Effect of platelet count and hematocrit on the coagulability of heparinized blood.

The coagulability of heparinized blood is shown to be a function of platelet and red cell concentrations. Thrombelastrographic tests were conducted on celite-activated fabricated whole blood samples with heparin concentrations ranging from zero to 1.46 units per ml of plasma, hematocrits from zero to 50% and platelet counts from zero to 300,000/mm3. The thrombelastograph provides three useful parameters of coagulability in native and heparinized blood: clot time, rate of clot stiffening and final clot stiffness. Of these, only the clot time is determined with the common clotting tests, while the rate and final clot stiffness are measures of clot quality that are found to be particularly sensitive to thrombocytopenia. The test results indicate (i) increases of platelet concentration produce the expected decrease in clot time, increase in rate of stiffening, and increase in final stiffness; (ii) increases of the red cell concentration from zero to 20% hematocrit, produce nonlinear increases in clotability, while further increases beyond 20% hematocrit produce no additional effects if the heparin concentration is less than 1.2 units/ml. Quantative relations are derived between the thrombelastographic variables, heparin concentration, and platelet concentration for those samples with hematocrits greater than 20%. These data indicate further experiments for the study of possible interaction between cellular blood elements and heparin.

Animals↗

PubMed2000

Very low platelet counts in post-transfusion purpura falsely diagnosed as heparin-induced thrombocytopenia. Report of four cases and review of literature.

Differential diagnosis between post-transfusion purpura (PTP) and heparin-induced thrombocytopenia (HIT) can be difficult in the initial stages of thrombocytopenia, as the early clinical presentations are often similar. Four patients are described who were suspected clinically of suffering from HIT. All four patients had recent blood transfusions and platelet alloantibodies, thus the diagnosis of PTP was made. One lethal gastrointestinal and one retroperitoneal hemorrhage developed in two of the four patients. Unusually, one patient was male and two different platelet alloantibodies were present in his serum; in another patient platelet alloantibodies and HIT-antibodies were detectable. To arrive at the right diagnosis as quickly as possible is vitally important since treatment, which has to be initiated promptly, is very different for the two syndromes. Thus, we suggest that in patients where HIT is suspected, additional information should be sought. If features consistent with PTP (such as a recent blood transfusion or a marked drop in platelet count to below 15 Gpt/L) are present, we recommend parallel testing for platelet alloantibodies to rule out PTP.

Acute Disease↗

PubMed1988

Percutaneous umbilical cord blood sampling in the evaluation of fetal platelet counts in pregnant patients with autoimmune thrombocytopenia purpura.

Autoimmune thrombocytopenia purpura in pregnancy is associated with fetal thrombocytopenia. Twenty-one patients with autoimmune thrombocytopenia purpura (22 fetuses) underwent 26 umbilical cord punctures to assess the fetal platelet count. Blood could not be obtained from one fetus. Thrombocytopenia (less than 150,000/microL) was found in five cases, but in none was it of sufficient degree to preclude vaginal delivery. Persistent fetal bradycardia necessitating emergency cesarean delivery occurred in two cases. Umbilical cord puncture was found to be technically more difficult in the term fetus than in the second-trimester fetus studied in previous investigations.

Adolescent↗

PubMed1989

[Hemorheological studies on platelet counts and size in normal pregnancy and pregnancies with preeclampsia and intrauterine growth retardation].

It has been reported that preeclampsia and pregnancy resulting in intrauterine growth retardation (IUGR) are associated with high hematocrits. The relations between hematocrits (Ht) and platelet volumes in normal and abnormal pregnancies were investigated to clarify a hemorheological effect on formation of microthrombus. 1) In normal pregnancy, Ht was decreased from 12-19 weeks gestation and reached its lowest level at 28-31 weeks gestation. The mean platelet volume (MPV) was decreased from 20 to 31 weeks gestation but markedly increased from 38 to 41 weeks gestation. The platelet count (Pl) remained unchanged during pregnancy. 2) In severe type of preeclampsia, at 28-37 weeks gestation Ht and MPV were markedly increased and Pl was markedly decreased at 38-41 weeks gestation as compared with normal pregnancies. 3) Mothers who delivered IUGR had a much higher level of Ht at 28-35 weeks gestation and MPV level from 38 weeks gestation than in normal mothers. As the volume of young platelets is large, increased MPV is suggestive of the occurrence of platelet consumption. From these results, it was suggested that microcirculatory disturbances such as higher blood viscosity due to hemoconcentration and microthrombus formation were related to the onset of preeclampsia or IUGR.

Blood Platelets↗

PubMed1995

Efficacy and safety of plateletpheresis by donors with low-normal platelet counts.

Our practice is to defer donors with blood platelet (PLT) counts of < 180 x 10(9)/L because PLT yields are low, when compared to PLT units collected from donors with higher counts. In an attempt to minimize deferral, we determined whether 33 donors, who repeatedly demonstrated low-normal PLT counts (150-180 x 10(9)/L) on multiple occasions during the prestudy period. might safely donate satisfactory apheresis PLT units simply by extending the apheresis collection time by 20 min (men) and 40 min (women). Repeat plateletpheresis procedures were scheduled at > or = 28-day intervals. The mean PLT yield (N = 92) was 5.8 x 10(11) with 97% of units containing > or = 4.0 x 10(11) PLTs. Although donors entered the study only after they had repeatedly exhibited predonation PLT counts of < 180 x 10(9)/L, PLT counts were not always below this level at the time of study collections. However, analyzing only donations with true predonation PLT counts of < 180 x 10(9)/L (N = 35), the mean PLT yield was excellent-5.4 x 10(11) with 97% of units containing > or = 4.0 x 10(11) PLTs. The average fall in donor blood PLT counts (pre-vs. postdonation) was 36%, with only ten of 99 postdonation counts being < 100 x 10(9)/L; the lowest was 69 x 10(9)/L. Thus, extending the apheresis collection time permitted donors who in the past were routinely deferred because of low PLT counts to safely donate satisfactory PLT units.

Blood Donors↗

PubMed2004

Spuriously elevated automated platelet count in severe burns--a report of two cases.

Increasing use of automated analyzers in the hematology laboratory has resulted in enhanced accuracy of results. However, operators of automated analyzers and the end users utilizing the automated data need to be aware of factitious results which might be reported at times by these instruments. Case summaries of two patients with severe burns showing spuriously elevated automated platelet count are presented here.

Adolescent↗

PubMed2004

Spurious rise in the automated platelet count because of bacteria.

The era of automation in haematology, although improving the accuracy and precision of results, has also introduced the laboratory haematologist to a vast array of spurious parameters. The identification of these results is important so that inappropriate management decisions are avoided. The case presented here illustrates a spuriously raised automated platelet count resulting from bacterial overgrowth in the blood sample.

Adult↗

PubMedDate not supplied

Platelet count and the risk of bleeding in hospitalized patients with venous thromboembolism starting anticoagulant therapy.

In a series of patients with pulmonary embolism (PE) we have previously demonstrated that the risk of recurrent PE was inversely correlated to platelet count (PlC) levels. To find out whether PlC levels were also associated to a different incidence of heparin-related bleeding complications, we report our experience with 1,103 consecutive patients with venous thromboembolism (VTE) receiving full-dose heparin therapy. Six points of clinical and laboratory information were recorded on admission and then compared to the development of bleeding: the patient's age and sex; the etiology of VTE; the type of heparin used (unfractioned, UFH, vs. low-molecular-weight, LMWH), the presence or lack of PE findings on lung scan, and the PC levels on admission. Bleeding occurred in 64/1,103 patients (6%). Patients who bled were significantly older than those who did not (72 +/- 11 vs. 64 +/- 17 years; p = 0.0005). There were no significant differences in bleeding rate according to any of the risk factors that could have predisposed to VTE, but patients treated with UFH bled significantly more frequently than those on LMWH (48/636 vs. 16/467; odds ratio: 2.30; 95% confidence interval: 1.25-4.28). Finally, mean PlC levels were significantly lower at VTE diagnosis in patients who subsequently bled (227 +/- 112 vs. 262 +/- 110 x 10(9) liters-1; p = 0.01). The logistic regression analysis confirmed that all three variables were independent risk factors for bleeding complications. This is the first study to demonstrate that PlC levels (within the normal range) are inversely correlated with the risk of heparin-related bleeding. These findings may be interest not only from the point of view of pathogenesis but also clinically, as they may be used in the decision as to which VTE patients could receive heparin therapy at home.

Age Factors↗

PubMed1995

Short-term changes in the blood leucocyte and platelet count following different durations of high-intensity treadmill running.

Short-term changes in the blood leucocyte count after exercise are known to be dependent on the intensity of exercise performed. The aim of the present study was to investigate the effects of the duration of high-intensity exercise on changes in the leucocyte and platelet count during the early recovery period. On separate occasions following a standard warm-up, eight healthy subjects (six males, two females) ran at a constant speed of 5.6 m s-1 (20 km h-1) on a level treadmill for 30, 60, 90, 120 or 150 s or to fatigue. Heart rates were increased to near maximal levels within 30 s of exercise. Significant increases in the blood leucocyte count occurred after all exercise durations compared with baseline (pre-exercise) levels. Running for 30 s increased the blood leucocyte count by 35 +/- 10% (x +/- S.D.). Running for 60 s increased the blood leucocyte count by 57 +/- 16%, but running for longer durations did not produce any further significant increase in the immediately post-exercise blood leucocyte count. After exercise to exhaustion, the leucocyte count had increased by 63 +/- 17%. This was mainly due to an increase of lymphocytes (114 +/- 20%) rather than neutrophils (34 +/- 7%). At exhaustion, plasma volume had decreased by 15.9 +/- 2.6% compared with pre-exercise. During 5 min of recovery from exercise, the leucocyte count fell significantly (after 30 and 60 s of running), remained unchanged (90 and 120 s) or increased significantly (150 s and fatigue) compared with immediately post-exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Epidural anesthesia in pregnant patients with low platelet counts.

A number of patients demonstrate thrombocytopenia in the peripartum period. One hundred four patients with unexplained transient periparturient thrombocytopenia were found over a nine-month period. Sixty-one of them received epidural anesthesia without neurologic sequelae. Epidural anesthesia is safe if the platelet count exceeds 100 x 10(9)/L in otherwise healthy women.

Anesthesia, Epidural↗

PubMed1975

Elevated platelet count and megathrombocyte number in sickle cell anemia.

Eight adult patients with sickle cell anemia were followed over a 6-mo period. During this time all patients had elevated plateletcounts, 1.7-fold (mean, 438,398 +/- 86,223), and megathrombocyte numbers, 2.3-fold (mean, 79,535 +/- 38,907), during asymptomatic periods. These data are interpreted as suggesting that the elevated platelets and megathrombocytes in asymptomatic sickle cell patients result from lack of splenic sequestration. During three crises in two patients, both megathrombocyte number and platelet count fell significantly. It is speculated that platelets may be associated with the pathology in this disease. Platelet function studies performed during crises, therefore, must take into account the number of megathrombocytes.

Adult↗

PubMed2001

Sustained remission of platelet counts following monoclonal anti-CD20 antibody therapy in two cases of idiopathic autoimmune thrombocytopenia and neutropenia.

Idiopathic autoimmune thrombocytopenia and neutropenia (ITN) is a primary haemocytopenic disorder clinically characterised by recurrent mucocutaneous bleeding episodes and infections. Unlike in simple idiopathic thrombocytopenic purpura, the platelet deficiency of ITN tends to be chronic and difficult to treat. We describe two patients with ITN who obtained sustained remission of their platelet counts after therapy with the chimeric monoclonal anti-CD20 antibody Rituximab. In one of two cases, Rituximab also induced prolonged normalisation of the neutrophil count and disappearance of auto-antibodies. Our observations indicate that disturbed B-cell function plays a central role in the pathogenesis of ITN. Anti-CD20 antibody therapy seems to constitute a safe and efficient alternative to corticosteroids for the management of ITN patients with chronic thrombocytopenia.

Adult↗

PubMed1991

Heparin-associated thrombocytopenia in a patient with polycythemia vera: the importance of a marked drop in platelet count.

The present report describes a patient with polycythemia vera who developed a severe arterial and venous thrombosis caused by systemically administered heparin. An immunologic implication has been proposed as pathophysiological mechanism of this heparin-associated thrombocytopenia and thrombosis syndrome. It is suggested, however, that a strong decrease in platelet count as occurred in this patient leads to a higher chance of developing this complication.

Female↗