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PubMed1997

[Improvement of bleeding tendency and normalized platelet count increment following splenectomy in a patient with refractory anemia].

A 72-year-old woman with refractory anemia had severe bleeding tendency. Since 1994, platelet transfusions (10 units three times per week) were unable to maintaining her platelet count over 10 x 10(3)/ microliter. Her hemoglobin was decreased to 3.9 g/dl as a result of bleeding from early gastric cancer. At one-hour after posttransfusion corrected platelet count increment (1-hour CCI) was slightly low, as 14 x 10(3)/microliter/m2. A 24-hour posttransfusion CCI (24-hour CCI) and the (24-hour CCI)/(1-hour CCI) ratio were markedly low, as 0.5/microliter/m2 and 0.36, respectively. Anti-HLA antibody was not detected. The ineffectiveness of platelet transfusion was suspected to be highly associated with splenomegaly. Her spleen had been gradually increased in size since the first clinical examination. She underwent both subtotal gastrectomy and splenectomy, while receiving 40 units of platelet transfusion. After splenectomy, the 1-hour CCI and the (1-hour CCI)/(24-hour CCI) ratio markedly improved (76 x 10(3)/microliter/m2 and 0.79, respectively). Cutaneous bleeding halted and there have been no further episodes, despite less frequent platelet transfusions. This is the first report in which bleeding tendency and CCI were improved by splenectomy in a case of myelodysplastic syndrome.

Aged↗
PubMed1978

Prognostic value of blood platelet counts, coagulation factors and serum fibrin/fibrinogen degradation products (FDP) in acute infections.

Platelet counts, P&P, factor V and fibrin/fibrinogen degradation products (FDP) in serum were determined in 96 patients with 100 episodes of acute infections. The aim of the study was to evaluate the possible correlation between the tests, separately and in combination, and the outcome of the patients. The prognostic value was found to be dubious (0.05 greater than P greater than 0.01) as regards both a low platelet count and a decreased level of P&P and very low (P greater than 0.2) as regards factor V. On the other hand, the demonstration of a raised S-FDP as well as the presence of more than one pathological test was of distinct prognostic value (P less than 0.001). It is concluded that coagulation tests are useful as supportive aids in the prognostic evaluation of patients with acute infectious diseases.

Acute Disease↗
PubMed1991

The platelet count as a simple measure to distinguish inflammatory bowel disease from infective diarrhoea.

A total of 212 adult patients with infective diarrhoea and 27 with inflammatory bowel disease (IBD), admitted consecutively to an infectious disease unit, were studied in order to determine whether clinical features and laboratory measurements performed on admission identified cases of IBD. Long-standing diarrhoea, blood in the faeces, anaemia, leucocytosis, thrombocytosis, raised ESR and a reduced concentration of serum albumin were more common in patients with IBD (P less than 0.05). The most striking difference was in the platelet count with 59% patients with IBD and 1.6% patients with infective diarrhoea having platelet counts greater than 450 x 10(9)/l. A raised platelet count in a patient admitted to hospital with 'acute gastro-enteritis' suggests IBD.

Adult↗
PubMedDate not supplied

Effect of anagrelide on platelet count and function in patients with thrombocytosis and myeloproliferative disorders.

BACKGROUND: Anagrelide is a quinazolin compound developed initially as an inhibitor of platelet aggregation. Since "in vivo" studies demonstrated that it was responsible for thrombocytopenia in humans, anagrelide has been used recently in a small number of patients with thrombocytosis and myeloproliferative disorders. Platelet count was well controlled in the large majority of patients, and only minimal side effects were observed. PATIENTS: Eight patients (5 with essential thrombocythemia, 2 with chronic granulocytic leukemia, and 1 with idiopathic myelofibrosis) received anagrelide (induction dose 4 mg/die; mean maintenance dose 2 mg/die; mean observation time 26 weeks). Complete blood counts were determined 4 times during the first month, and subsequently every month. "In vivo" and "ex vivo" platelet function was studied before anagrelide and after 4 and 10 days of therapy. RESULTS: Platelet count was reduced and maintained below 500 x 10(9)/L in 5 of 8 patients. Headache, palpitation/tachycardia, gastrointestinal symptoms and a decrease in hemoglobin were the side effects. Anagrelide did not modify the leukocyte count or "in vivo"/"ex vivo" platelet function. CONCLUSIONS: Anagrelide may control thrombocytosis in patients with myeloproliferative disorders, even when traditional drugs have failed. When required, anti-aggregating drugs may be associated with anagrelide, since it has no effect on platelet function.

Adult↗
PubMed1989

Flow cytometric analysis of megakaryocytes from patients with abnormal platelet counts.

Megakaryocytes (MKs) from 40 patients with quantitative platelet disorders and 19 normal volunteers were analyzed by flow cytometry for size, fine cell internal structure and granularity, membrane expression of the glycoprotein (GP) IIb/IIIa complex, and for ploidy distribution. Analysis was performed on unfractionated minimally manipulated marrows obtained from routine bone marrow aspirates. MKs were labeled with a fluorescent lineage-specific monoclonal antibody to the GPIIb/IIIa complex followed by DNA staining with propidium iodide. Eight hundred to 3,000 MKs were analyzed in each sample. The modal ploidy distribution in normals was 16N, comprising about half of the megakaryocytic population, with 22.6% of the cells less than or equal to 8N and 22.0% greater than or equal to 32N. Twelve thrombocytopenic patients with decreased marrow MKs on biopsy (mean platelet count [MPC] 44,600/microliters) showed an increase in low ploidy cells with 53.2% less than or equal to 8N (P less than .01); cell size was reduced in three patients when compared to normal cells of identical ploidy (P less than .05). Eight thrombocytopenic patients with enhanced platelet destruction (with normal or increased MKs on biopsy and shortened platelet survival; MPC 41,400/microliters) showed an increased proportion of high ploidy cells greater than or equal to 32N to 39.2% (P less than .01). Increased cell size and granularity were found in four of these patients (P less than .05). Six patients with thrombocytopenia secondary to multiple mechanisms affecting both platelet production and destruction (MPC 66,700/microliters) showed no shift in ploidy. Four patients with primary thrombocytosis (two with thrombocythemia and two with polycythemia vera; MPC 822,500/microliters) showed a marked shift toward high ploidy cells with 42.3% greater than or equal to 32N and 7.6% greater than or equal to 64N cells (P less than .01). The shift was accompanied by a marked increase in cell size and granularity in the patients with thrombocythemia. Ten patients with thrombocytosis secondary to chronic blood loss, malignant or inflammatory disorders (MPC 714,000/microliters), showed variable distributions with four patients exhibiting a shift in ploidy to the right similar to that found in the patients with increased platelet destruction. Based upon the present data, flow cytometric ploidy distribution may be diagnostically useful in thrombocytopenic patients by discriminating between disorders of platelet production and destruction. (ABSTRACT TRUNCATED AT 400 WORDS)

Bone Marrow↗
PubMed2000

The bleeding risk and natural history of idiopathic thrombocytopenic purpura in patients with persistent low platelet counts.

BACKGROUND: No firm data are available on the natural history of idiopathic thrombocytopenic purpura (ITP) or on mortality rates or frequency of major bleeding episodes associated with this condition. The disease is thought to have a relatively benign course, despite the frequent occurrence of very low platelet counts. This prevailing conception often guides therapeutic decisions. OBJECTIVE: To estimate the bleeding risk of ITP involving persistent low platelet counts (<30 x 10(9)/L) and its impact on prognosis. DESIGN: Age-adjusted bleeding risk was derived from a pooled analysis of ITP clinical series based on a systematic literature search. The risk estimate was incorporated into a Markov model to determine its impact on prognosis. RESULTS: Seventeen case series complied with inclusion criteria, including 1,817 patients with ITP. There were 49 cases of fatal hemorrhage over an estimated 1,258 to 3,023 patient-years at risk. The rate of fatal hemorrhage before age adjustment was estimated at between 0.0162 and 0.0389 cases per patient-year. Age-adjusted rates were 0.004, 0.012, and 0.130 cases per patient-year for age groups younger than 40, 40 to 60, and older than 60 years, respectively. Predicted 5-year mortality rates ranged from 2.2% for patients younger than 40 years to 47.8% for those older than 60 years. A 30-year-old woman remaining thrombocytopenic due to ITP was predicted to lose 20.4 years (14.9 quality-adjusted life years) of her potential life expectancy. At age 70, predicted loss was 9.4 years (5.0 quality-adjusted life years). CONCLUSIONS: Idiopathic thrombocytopenic purpura with persistent low platelet counts carries a grave prognosis. Therefore, an active therapeutic approach in the clinical management of affected patients should be considered. In view of the significant potential implications of the model results, we call for initiating a well-designed prospective inception cohort study of patients with ITP.

Adult↗
PubMed2002

Clinical significance of the changes of platelet counts and serum thrombopoietin levels in chronic hepatitis C patients treated with different doses of consensus interferon.

Thrombocytopenia is commonly seen in patients with cirrhosis. Both splenomegaly and inadequate thrombopoietin (TPO) production by the cirrhotic liver are responsible for thrombocytopenia. In addition, thrombocytopenia is frequently observed in chronic hepatitis patients who received interferon therapy, and may even lead to the discontinuation of treatment. The aim of this study is to evaluate the clinical significance of the changes of platelet counts and serum TPO levels in chronic hepatitis C patients treated with different doses of consensus interferon (CIFN). Data from 75 chronic hepatitis C patients who received subcutaneous injection of either CIFN 9 (25 patients) or 3 &mgr;g (26 patients) or placebo (24 patients), three times a week for 24 weeks, were analyzed from a randomized controlled study. All patients received a 24-week observation period after the end of the treatment. The results showed a significantly higher degree of decrease in platelet counts and elevated serum TPO in patients receiving CIFN 9 or 3 &mgr;g as compared with placebo at week 12 and week 24 of treatment, respectively. These changes were more obvious in patients receiving CIFN 9 &mgr;g than in patients receiving CIFN 3 &mgr;g. However, both the decrease of platelet counts and elevated serum TPO levels returned to the baseline values after stopping CIFN therapy. Lower hepatic fibrosis score, lower pretreatment serum HCV RNA level, genotype non-1b infection and patients with sustained response to CIFN were manifested with higher degree of serum TPO elevation in response to the CIFN-induced thrombocytopenia. Multivariate logistic regression analysis showed that an age of less than 45 years and a serum TPO level elevation greater than 50% of baseline level at week 12 of CIFN treatment were significantly independent predictors associated with the sustained response to the CIFN treatment. In conclusion, the changes of platelet counts and serum TPO levels in chronic hepatitis C patients during CIFN therapy were reversible, and the degree of changes were more prominent in higher doses of CIFN treatment. The serum TPO response to CIFN-induced thrombocytopenia may serve as a marker for the degree of liver fibrosis, and also as a parameter for predicting therapeutic response.

Journal Article↗
PubMed1995

Influence of hematocrit and platelet count on impedance and reactivity of whole blood for electrical aggregometry.

Previous studies have shown that differing qualities of blood specimen seem to influence whole blood electrical aggregometry (WBEA), making it difficult to standardize the method. The aim of this study was to investigate the impact of hematocrit (HCT) and platelet count (PLC) on in vitro platelet aggregation in citrated whole blood (CWB) in order to compensate for their possible effects on impedance aggregometry. Red blood cells and blood platelets were isolated from fresh citrated whole blood taken from 15 healthy donors (mean age = 26 years) and recombined to 20 physiologically relevant combinations of hematocrit and platelet count (HCT: 20-50, PLC: 100-500). Platelet aggregability was measured using WBEA with three different triggers. A special-purpose software package was used in this study, ensuring proper calibration, acquisition, and evaluation of analogue to digital converted data, allowing the calculation of a set of characteristic parameters of each impedance curve. Most of the linear regressions showed that all parameters significantly depend on HCT and PLC. Furthermore, we found interactions of both variables, making it impossible to focus on the effects of one of the investigated variables only. The outcome of this study is a set of dependences, allowing the calculation of regressions for in vitro aggregation in whole blood, enabling a comparison of blood of any quality with each other, regardless of the variables HCT and PLC. Together with the previously defined dependence of sample age on WBEA data, this step should help to make this technique a more reliable and practicable clinical tool, making it suitable for daily routine investigations.

Adult↗
PubMed2000

Risk factors for adverse maternal outcomes among women with HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome.

OBJECTIVE: This study was undertake to determine risk factors for adverse maternal outcomes among women with HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. STUDY DESIGN: Maternal medical records of pregnancies complicated by HELLP syndrome managed between July 1, 1992, and April 30, 1999, were reviewed. Risk factors evaluated included maternal age, parity, race, previous preeclampsia, chronic hypertension, gestational age at diagnosis, mean arterial blood pressure, nadir blood platelet count (<50,000 cells/microL vs > or =50,000 cells/microL), and peak serum levels of aspartate aminotransferase and lactate dehydrogenase. Maternal outcome variables analyzed included eclampsia, abruptio placentae, disseminated intravascular coagulopathy, pulmonary edema, pleural effusion, ascites, acute renal failure, liver hematoma, need for transfusion of blood products, cesarean delivery, and death. Statistical analysis was performed with the Student t test, the chi(2) test, and logistic regression analysis. RESULTS: A total of 183 women with HELLP syndrome were studied. Eclampsia was present in 6%, abruptio placentae was present in 10%, and disseminated intravascular coagulopathy was present in 8%. Forty-one women (22%) required transfusion of blood products. Incidence of eclampsia significantly decreased with increasing gestational age, from 16% at < or =28 weeks' gestation to 3% at >32 weeks' gestation (P <.05) and was higher among African American patients than among white patients (12% vs 3%; P <.05). Logistic regression analysis showed an independent relationship between eclampsia and race (P <.05). Incidence of abruptio placentae was higher among women with previous preeclampsia than among women without this clinical history (26% vs 5%; P <.05). Disseminated intravascular coagulopathy was significantly associated with abruptio placentae (P <.0001) and acute renal failure (P <.0001). A nadir platelet count of <50, 000/microL, a peak serum aspartate aminotransferase level of >150 U/L, and a peak serum lactate dehydrogenase level of >1400 U/L were not independent risk factors for adverse outcome. CONCLUSIONS: Among women with HELLP syndrome, African American race is a risk factor for eclampsia. Both acute renal failure and abruptio placentae are associated with disseminated intravascular coagulopathy. Laboratory parameters of HELLP syndrome are not independent risk factors for adverse maternal outcome.

Abruptio Placentae↗
PubMed2001

An interlaboratory study of a candidate reference method for platelet counting.

A multinational interlaboratory task force explored the important variables of platelet reference counting and developed a candidate flow cytometric reference method based on the RBC/platelet ratio. A multicenter comparison was performed to determine whether the method met the necessary criteria and was precise enough to be recommended as a new reference method. Each laboratory analyzed serial dilutions of normal specimens, stabilized material, and at least 60 patient specimens with a range of platelet counts from 1 to 400 x 10(3)/microL (1-400 x 10(9)/L). Pooled analysis of the serial dilutions showed that RBC-platelet and RBC-RBC coincidence events became negligible at sufficiently high dilutions (i.e., > 1:1,000). All laboratories demonstrated excellent intra-assay and acceptable interlaboratory precision. Two antibodies (CD61 and CD41) were used for identifying platelets and individually gave acceptable results, but in a minority of samples, staining differences were observed. The optimum method thus uses a double-labeling procedure with a final dilution factor of 1:1,000. The study demonstrated that this method meets the criteria for a reference platelet count.

Anticoagulants↗
PubMed2004

The urine trans, trans muconic acid biomarker and platelet count in a sample of subjects with benzene exposure.

Benzene exposure is of particular concern because of ongoing exposure to thousands of workers. Prolonged exposure can cause chronic toxicity, especially hematologic disorders. The effects of benzene on red blood cells and white blood cells have been clearly proposed; however, the effect of benzene on platelets has not been studied. The correlation between the level of trans, trans muconic acid (ttMA), a urine metabolite of benzene, and the platelet count of subjects occupationally exposed to benzene was studied. Thirty volunteers who were occupationally exposed to benzene were investigated for both urine ttMA levels and platelet parameters. According to the regression analysis, no significant correlation existed between urine ttMA level and any platelet parameters (p > 0.05). However, although there is no statistical significance, the platelet count and PCT decreased while the urine ttMA increased. In addition, using the upper normal limit ttMA level as the cutoff level, the statistically significant lower platelet count and PCT was observed in the subjects with urine ttMA higher than upper normal limit. This report is the first world report on this topic and the results from this study can provide good basic data for further understanding the effect of benzene exposure on the platelet.

Benzene↗
PubMed1997

Heparin-related thrombosis despite normal platelet counts in vascular surgery.

BACKGROUND: Acute graft thrombosis is a severe complication in vascular surgery that may require limb amputation or even cause death. Because nearly all patients undergoing vascular surgery have had previous exposure to heparin, the presence of heparin-related anti-platelet antibodies typical for heparin-associated thrombocytopenia (HAT) is one underlying possible mechanism of acute graft thrombosis. Although thrombocytopenia is a typical finding of HAT, it is not clear whether the occurrence of clinically important HAT is necessarily associated with thrombocytopenia. PATIENTS AND METHODS: Ten out of 246 patients undergoing vascular surgery were diagnosed with HAT because of otherwise unexplained acute graft thrombosis that required recurrent surgical interventions. RESULTS: In all of the 10 patients, heparin-related anti-platelet antibodies were detected although the platelet counts were within the normal range. When HAT was diagnosed, heparin administration was stopped and, after autoantibody cross-reactivity with the heparinoid Danaparoid had been excluded, anticoagulation was continued using this anticoagulant. After heparin therapy was discontinued none of the 10 patients developed further thrombotic complications. CONCLUSION: The data presented demonstrate clearly that a normal platelet count does not exclude the possibility of HAT. As a consequence of this, HAT should be suspected in patients who develop thrombotic complications during heparin treatment, regardless of the actual platelet counts.

Adult↗
PubMed1985

The absence of influence of acetylsalicylic acid (ASA) on the transient decrease in platelet counts observed after infusion of bleomycin and vinblastine.

Retrospectively we observed an early-onset transient decrease in platelet counts in a group of patients treated with cisplatin, vinblastine and bleomycin. Though less pronounced, the decrease was also found in a prospectively studied group of patients treated with bleomycin, etoposide and cisplatin, but was absent after treatment with etoposide ad cisplatin. In a randomized cross-over study acetylsalicylic acid (ASA) appeared not to prevent the drop in platelet counts. Bleomycin appears to induce an early-onset transient decrease in platelet numbers, possibly by direct or indirect platelet lysis. Vinblastine may have a synergistic effect to this phenomenon.

Adult↗
PubMed2001

Decrease in platelet count during saturation diving.

BACKGROUND: The change in platelet count (PC) occurring during saturation diving has rarely been discussed. We set out to clarify the details of this change in PC, and its relationship with: i) the storage depth and duration of the saturation dive, and ii) the presence of decompression bubbles. METHODS: In a total of 42 divers, the change in PC was measured in 8 simulated saturation dives (1992-1998) using a Deep Diving Simulator with decompression procedures based on the modified DUKE-GKSS schedule. Blood samples were taken before the dive, at the bottom (twice), during decompression, on surfacing, and about 1 wk after surfacing. Decompression bubbles were examined by ultrasonic M-mode echocardiography. RESULTS: PC (mean +/- SD x 10(4) x microl(-1)) was 23.9 +/- 4.85, 24.9 +/- 4.9, 24.2 +/- 4.8, 19.2 +/- 4.4*, 20.1 +/- 4.5*, 25.0 +/- 5.1 on the occasions listed above (*= p < 0.05 vs. pre-dive). The PC showed no correlation with either storage depth or dive duration. Decompression bubbles were detected during decompression in only 2 divers (4.8%), and the bubbles disappeared immediately after surfacing. In these 2 divers the decreases in PC values from baseline to the middle of decompression and on surfacing were 2 and 2.7 x 10(4) x microl(-1), and 3.4 and 1.7 x 10(4) x microl(-1) respectively. No diver complained of decompression sickness. CONCLUSION: The magnitude of the decrease in PC (< 5 x 10(4) x microl(-1)) and the time to recover to the pre-dive value (< 1 wk) suggests that changes in PC during saturation diving should not cause any clinical problems. The mechanisms underlying the decrease in PC remain unclear.

Adult↗
PubMed2003

[Three cases of idiopathic thrombocytopenic purpura showing an increase in the platelet count following clarithromycin treatment].

Macrolides have immuno-modulatory effects as well as anti-bacterial effects. We successfully treated three idiopathic thrombocytopenic purpura (ITP) patients with clarithromycin (CAM). Case 1: A 69-year-old male ITP patient was treated with CAM at a dose of 400 mg/day. His platelet count increased from 5.6 x 10(4)/microliter to 10.1 x 10(4)/microliter. Case 2: A 72-year-old male ITP patient was treated with CAM at the same dose. The platelet count increased from 1.3 x 10(4)/microliter to 12.3 x 10(4)/microliter. Case 3: A 68-year-old female ITP patient was treated with CAM at the same dose. The platelet count increased from 2.3 x 10(4)/microliter to 13 x 10(4)/microliter. These facts suggest that CAM is useful in the treatment of ITP.

Aged↗