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Efficacy of Helicobacter pylori eradication in raising platelet count in adult patients with idiopathic thrombocytopenic purpura.

BACKGROUND AND OBJECTIVES: There are data consistent with an association between idiopathic thrombocytopenic purpura (ITP) and Helicobacter pylori (HP) infection. In addition, a significant increase of platelet count following HP eradication has been reported in a proportion of ITP patients. We describe here our experience on the efficacy of anti-HP treatment in ITP patients. DESIGN AND METHODS: Between December 1998 and May 2001 sixteen adult patients with ITP and documented HP infection were treated with standard antibiotic therapy for HP eradication (amoxicillin and clarithromycin plus pantoprazole combination). Of these patients, 7 had untreated ITP with mild/moderate thrombocytopenia (median platelet count 70x10(9)/L, range 41-91), 5 had relapsed following a previous steroid treatment (median platelet count 39x10(9)/L, range 30-90) and 4 were refractory to steroids (median platelet count 18.5x10(9)/L, range 9-30). RESULTS: An improvement of platelet count was observed in 11/15 patients (73.3%) who achieved HP eradication. The difference between the mean platelet count SD before and after HP eradication was statistically significant (51.6 28.2x10(9)/L vs. 143.3 131.1x10(9)/L; p=0.01). Complete or partial responses were obtained in 11/16 treated patients (68.7%). This result still persisted after a median follow-up of 11.7 months. INTERPRETATION AND CONCLUSIONS: Our data confirm the efficacy of Helicobacter pylori eradication in increasing platelet count in adult ITP patients.

Adult↗

Lower platelet count in healthy centenarians correlates with dispersion of the QT interval.

BACKGROUND AND AIMS: Centenarians display a lower incidence of vascular ischemic events. A high platelet count and increased QT dispersion (QTd) represents a risk factor for cardiovascular events. The aim of this study was to evaluate platelet count and QTd in healthy centenarians and to establish correlations between these two indices. METHODS: 16 healthy centenarians (4 males, 12 females, range 100-105 years) living in a municipality of Eastern Sicily, and 40 healthy control subjects, divided into two groups: group A (N=20), age range 45-65 years, 7 males, 13 females; and group B (N=20), range 65-85 years, 6 males, 14 females, were examined. Platelets were counted using a blood analyzer and QTd was measured in standard 12-lead electrocardiograms. Differences in platelet count were assessed by one-way analysis of variance (ANOVA) and the Bonferroni test. Correlation coefficients between platelet count and QTd were calculated with the Spearman rank test. RESULTS: Centenarians showed a lower platelet count compared with controls, which was significant with respect to older controls, group B (p<0.05). QTd values did not significantly differ between centenarians and controls. A significant correlation between QTd and platelet count was evident in centenarians but not in controls. This correlation became evident in control subjects with a platelet count < or = 240,000/mm3. CONCLUSIONS: We hypothesize that a reduced number of platelets and the maintenance of normal QTd may contribute to extreme longevity and protect centenarians from cardiovascular events.

Aged↗

Elevated platelet count before ileal pouch-anal anastomosis for ulcerative colitis is associated with the development of chronic pouchitis.

Acute pouchitis (AP) after ileal pouch-anal anastomosis (IPAA) is common and easily treated. However, chronic pouchitis (CP) remains a difficult management problem and may represent a form of Crohn disease (CD) of the ileal pouch. Because CD patients have higher platelet counts than ulcerative colotis (UC) patients, we prospectively evaluated the association between preoperative platelet count and pouchitis development in 159 patients undergoing IPAA. Reactive thrombocytosis (RT) was defined as a platelet count > 450 x 10(9)/L. Median preoperative platelet count was 312 x 10(9)/L (range, 103 x 10(9)/L to 886 x 10(9)/L). One hundred twenty-five patients (79%) had a normal (150 x 10(9)/L to 450 x 10(9)/L) platelet count (-RT patient group). Twenty-eight patients (18%) had RT. Six patients (3%) had a platelet count below 150 x 10(9)/L. After a median follow-up of 13 months, 45 patients (28%) developed pouchitis. Pouchitis developed in 33 +RT patients (26%) versus 9 -RT patients (32%) (P = NS). UC patients who had +RT had a 25 per cent incidence of CP compared to only 7 per cent of those UC patients who had -RT (P = 0.03). The incidence of CP was significantly higher after IPAA in UC patients having thrombocytosis before surgery compared to UC patients having a normal platelet count before surgery.

Adolescent↗

[Assessing the significance of platelet count to in-vitro hemolytic test by roller pump].

This study was directed at estimating the value of platelet count in the course of in-vitro hemolytic tests by roller pump. Five paired in-vitro tests were conducted using the POLYSTAN pump(group A) and COBE pump(group B). The pumps ran 16 hours. The samples for platelet count and plasma-free hemoglobin were taken before pumping, and every 2 hours after 4 hours of pumping. The 2 groups' platelet count and plasma-free hemoglobin levels were found to be linearly increasing with the hours of pumping and linear regression analysis showed the platelet count and plasma-free hemoglobin were positively correlated. These data suggested that platelet count could be used as an index in evaluating the in-vitro hemolytic properties of blood pumps.

Assisted Circulation↗

Platelet counts in myocardial infarction, angina pectoris and peripheral artery disease.

Serial determinations of peripheral venous platelet counts were performed in 43 consecutive patients with acute chest pain. On admission, patients with acute myocardial infarction (AMI) had a significantly lower mean platelet count (p less than 0.05). Thereafter a further reduction was seen with steadily reduced platelet counts by about 20%, both in comparison with healthy controls (p less than 0.001) (n = 113) and patients with peripheral artery disease (PAD) without heart symptoms (p less than 0.005) (n = 54). The platelet number increased one week after admission and even thrombocytosis was observed. The changes in platelet number during AMI seem to parallel the changes in platelet function. Patients with PAD had normal mean platelet counts. Female patients as well as healthy subjects had significantly higher values than men (p less than 0.01).

Adult↗

Anagrelide for treatment of patients with chronic myelogenous leukemia and a high platelet count.

Chronic myelogenous leukemia (CML) is usually treated with hydroxyurea or interferon-alpha. In some patients high platelet counts develop although leukocyte counts are well controlled with these drugs. If in such a situation cytoreductive therapy has to be intensified by a increase of the dosage, anemia and leukocytopenia as well as adverse effects of the drugs are likely to occur. In twelve CML patients we have therefore combined the basic CML treatment with anagrelide. This drug which selectively reduces platelet counts has been shown to be efficacious in the control of thrombocytosis in essential thrombocythemia. The diagnosis had been confirmed in all CML patients by cytogenetic and/or molecular biological analysis. The median age of our group was 58 years. Five were women and seven men. All patients were on treatment with hydroxyurea, some of them had previously received treatment with interferon-alpha (alone or in combination with hydroxyurea), busulfan or melphalan. Prior to the initiation of anagrelide treatment the platelet count was between 970,000 and 3,600, 000/microl (median about 2,000,000/microl). Seven patients had thrombohemorrhagic complications. All twelve patients, experienced hematologic responses, since their platelet counts decreased to less than 600,000/microl. The median platelet count after reduction was 343,000/microl. The median dosage required to achieve these responses and to maintain them for a period of at least four weeks was 1.9 mg/day. Thrombohemorrhagic complications disappeared or did not recur in all symptomatic patients. Adverse effects were seen in 3/12 patients: headache (1), tachycardia (1), palpitation (1) and fluid retention (1). Whereas these symptoms were mild and transitory they caused one patient to request discontinuation of treatment. Currently five patients are still on treatment with anagrelide (median duration of treatment 11 months) while therapy had to be discontinued in the seven others because of bone marrow transplantation, development of osteomyelofibrosis, blast crisis or on patient request. In our experience anagrelide is a useful therapeutic adjunct when thrombocytosis in patients with CML cannot properly controlled alone with traditional drugs.

Aged↗

The effect of plateletpheresis on the Fenwal CS-3000 on donor platelet counts.

To evaluate the risk of significant plateletpheresis-induced thrombocytopenia in normal volunteer donors undergoing plateletpheresis less frequently than every 56 days and to help understand factors influencing platelet yield in these donors, pre- and postapheresis platelet counts (X 10(3)/microliter) and platelet yields were analyzed from 916 plateletpheresis procedures (Fenwal CS-3000) on 607 donors (405 men, 202 women). The mean preapheresis platelet count was 265 +/- 59 (SD) (range 155-650) (men 256 +/- 55 [170-444]; women 284 +/- 65 [155-650]; P less than .001, t-test). After an average platelet yield of 4.08 X 10(11), the mean postplatelet count was 185 +/- 46 (range 72-420) (men 184 +/- 42 [80-345]; women 194 +/- 52 [72-500]; P less than 0.1). The percent decrease in platelet count (mean 29.4 +/- 13, range -28.1-65.5) had positive correlations with platelet yield (P less than .01, r = 0.10), predonation platelet count (P less than .001, r = 0.29), and age (P less than .01, r = .10) and a negative correlation with weight (P less than .001, r = 0.18) Both the percent decrease and platelet yield were significantly higher in women than in men (P less than .001, t-test), and platelet yield was best predicted by preapheresis platelet count in both sexes (r = 0.65). The effects of plateletpheresis on donor platelet count thus vary widely among donors. Although a decrease of greater than 50% was not a rare event (5.9% of all procedures), in only three instances (0.3%) was the actual postapheresis platelet count below 100 (72, 94, 95). Thus, plateletpheresis in normal donors appears unlikely to produce clinically significant thrombocytopenia immediately after apheresis.

Adult↗

Correlation of platelet count with second-look laparotomy results and disease progression in patients with advanced epithelial ovarian cancer.

OBJECTIVE: To evaluate the significance of preoperative platelet counts in advanced epithelial ovarian cancer with respect to second-look laparotomy results and disease progression. METHODS: We prospectively evaluated 37 consecutive patients with advanced epithelial ovarian cancer who underwent primary surgical treatment. In addition to platelet counts, all patients were evaluated with respect to age, gravida, parity, and stage and grade of tumor. Thirty-six patients had stage III, and 1 patient had stage IV disease. Optimal debulking (diameter of residual tumor, less than 1 cm) was performed in all patients who subsequently received adjuvant chemotherapy (platin-paclitaxel). According to second-look laparotomy and follow-up results patients were divided into 2 groups. The first group had negative second-look laparotomy or no evidence of disease during follow-up (n = 20), and the second group had positive second-look laparotomy or progressive disease (n = 17). Sensitivity and specificity values were calculated for different cutoff values of platelet counts with receiver operating characteristic curve analysis. RESULTS: Age, gravida, and parity were not significantly different compared with controls (P >.05). Mean platelet counts were 371 x 109/L and 446 x 109/L in the first and second groups, respectively (P =.03). Different cutoff values of platelet counts for the diagnosis of thrombocytosis were evaluated. A cutoff value of 380 x 109/L had sensitivity 77% and specificity 60% for recurrence, whereas a cutoff value of 400 x 109/L had sensitivity 59% and specificity 65%. Area under the curve (+/- standard error) was 0.72 +/- 0.08 (P =.026). CONCLUSION: In patients with progressive disease and positive second-look laparotomy, preoperative platelet counts were significantly higher compared with patients with no evidence of disease on follow-up.

Carcinoma, Endometrioid↗

Spurious platelet counts in acute leukaemia with DIC due to cell fragmentation.

Automated platelet counts in a patient with newly diagnosed AML M5 with extreme leukocytosis were reported as 129, 166 and 121 x 10(9)/1. Routine blood films showed a corresponding number of platelet-sized particles, judged to be platelets. The patient was treated for DIC with low-dose heparin infusion. Platelet transfusions were not given initially. The patient died 14 h after admission from intracerebral haematoma. The origin of the platelet-sized particles seen in routine stained blood films was examined by cytochemical and immunological staining for peroxidase, non-specific esterase, CD 13 and CD 33. About 1/3 of the fragments had the same staining characteristics as the leukaemia cells, indicating leukaemia cell origin. Staining for platelet-specific antigen GpIIIa was positive only in 4% of the platelet-sized fragments, with a calculated true platelet count of 4 x 10(9)/1. The presence of cell fragments masquerading as platelets should be suspected in leukaemia patients with bleeding symptoms and normal or near normal platelet counts.

Acute Disease↗

Effect of age, gender, and platelet count on Sonoclot coagulation analysis in patients undergoing orthopedic operations.

OBJECTIVE: To assess the relationship between Sonoclot coagulation variables and age, gender, or platelet count in surgical patients without coagulation disorders. MATERIAL AND METHODS: This study included 136 patients undergoing orthopedic surgical procedures under spinal or epidural anesthesia. Whole blood was withdrawn preoperatively from each patient, and a Sonoclot analysis was performed within 2 minutes after the sample was obtained. The Sonoclot results were considered investigational and not used in the perioperative management of the patients. Variables from the Sonoclot graphs were analyzed statistically to determine any associations with age, gender, or platelet count. RESULTS: The Sonoclot baseline height was decreased in patients with lower hemoglobin levels, older age, and female gender. The upward slope from baseline to inflection (R1) was increased in female patients and older patients. In comparison with patients who had lower platelet counts, patients with higher platelet counts exhibited a shorter time to inflection, increased upward slope from inflection to peak (R2), shorter time to peak, increased downward slope from peak to plateau (R3), decreased time to plateau, and lower plateau height (P < or = 0.01 for all relationships). CONCLUSIONS: Sonoclot coagulation analysis reliably evaluates platelet count as an indicator of platelet function. Controlled studies are needed to examine the clinical usefulness of Sonoclot coagulation analysis in the diagnosis and treatment of perioperative coagulopathies and hemorrhagic complications.

Adult↗

Platelet count and function in children receiving sodium valproate.

To evaluate whether valproic acid (VPA) can cause thrombocytopenia and impaired platelet function, the authors prospectively studied 20 children (12 female and eight male; age range 4.9-9.2 years) before and after 6 months of VPA monotherapy. Fifteen healthy sex- and age-matched children served as control subjects. VPA was prescribed at normal dosages (19.7 +/- 9.9 mg/kg), and plasma levels were within the therapeutic range (60.1 +/- 16.5 microg/mL). At the first evaluation, no significant difference between patients and control subjects was observed for platelet count and function. At the second evaluation the platelet counts were significantly lower in the patients (194,200 +/- 37,800/microL; range 157,700-222,400) than in the control subjects (291,100 +/- 41,300/microL; range 261,000-332,500; P < 0.01). Significant differences occurred between patients and control subjects in the release of adenosine triphosphate (ATP) after collagen and adenosine diphosphate (ADP) stimuli and in aggregation after stimulation with collagen, ADP, and arachidonic acid. Significant correlations between platelet count, aggregation, and ATP release and VPA dosage and plasma concentration were also observed. VPA can cause a decreased platelet count and aggregation and ATP release impairment. These side effects can appear after a few months of therapy and with plasma valproate levels within the normal range. They do not seem to be associated with clinical symptoms, and drug discontinuation is not necessary.

Adenosine Triphosphate↗

Platelet count and thrombopoietic activity in patients with chronic renal failure.

The frequency of thrombocytopenia in patients with chronic renal failure (CRF) is controversial. This study was undertaken to investigate the platelet count in 55 patients with end-stage renal disease on maintenance hemodialysis and in 19 patients with CRF before hemodialysis had begun. In both groups platelet counts were similar and significantly reduced, 175,000 +/- 6,500 and 181,000 +/- 10,800 compared to 253,000 +/- 3,700/mm3 in the control (p less than 0.0001). 31% of hemodialysis patients had thrombocytopenia (platelet count less than 150,000/mm3). The megakaryocyte number in their bone marrow aspirate was not reduced. Primary renal disease, androgen treatment or parathyroidectomy did not affect the platelet count. Thrombopoietic activity using 75Se-selenomethionine incorporation into platelets measured in 7 thrombocytopenic patients was found to be reduced, 6.77 +/- 0.29 vs. 9.06 +/- 0.27 (X 10(-2)%: p less than 0.001). This study shows that the platelet count is reduced and mild thrombocytopenia is frequent in patients with CRF. A possible cause for the platelet count reduction is insufficient thrombopoietic activity.

Adolescent↗

A critical analysis of platelet counting methods.

A careful analysis of platelet counting methods, including an assessment of accuracy, was done using data from the College of American Pathologists Comprehensive Hematology Survey preserved platelet suspension specimen (H-32-1976). Comparisons between methods suggest systematic biases probably related to the calibration methods used for automated instruments. Falsely elevated counts occurred with manual methods and one light-dispersion system. Methods for calibration and continuing quality assurance of platelet counting are proposed.

Automation↗

Rearrangements of chromosome 3 involving bands 3q21 and 3q26 are associated with normal or elevated platelet counts in acute nonlymphocytic leukemia.

Fourteen patients with acute nonlymphocytic leukemia (ANLL) or dysmyelopoietic syndromes were found to have abnormalities involving the long arm of chromosome 3. In eight patients, the structural rearrangements involved both bands 3q21 and 3q26 and included t(3;3) (four patients), inv(3) (three patients), and ins(5;3) (one patient). Before treatment, seven of these eight patients had platelet counts above 100,000 per microliter, five had normal or elevated platelet counts, and four had significantly elevated platelet counts (600,000 to 1,731,000 per microliter). In each of the eight cases, normal or elevated platelet counts were associated with marked abnormalities of megakaryocytopoiesis, including increased numbers of megakaryocytes and numerous micromegakaryocytes. Classification within the French-American-British system was difficult in most of these cases; however, the leukemia in five of the eight patients with abnormalities of chromosome 3 that involved both bands 3q21 and 3q26 was classified as M4. The remaining six of the 14 patients had translocations between chromosome 3 and another chromosome. None involved both bands 3q21 and 3q26, and a break in either q21 or q26 was noted in only two patients. One of the six, who had ANLL (M4) with a normal platelet count, had a 3;5 translocation which involved band 3q25. These data suggest that in patients with ANLL, abnormalities of chromosome 3 which simultaneously involve bands 3q21 and 3q26 are associated with unusually high platelet counts.

Adult↗

Post partum platelet count in maternal blood.

BACKGROUND: Thrombocytopenia in pregnancy, during and after delivery can be an indicator of serious preeclampsia or any condition accompanied by disseminated intravascular coagulation (DIC). In order to recognize thrombocytopenia, it is important to know the expected platelet count in healthy women. Literature search gave no information regarding changes of platelet count in healthy women shortly after uneventful pregnancies and uncomplicated deliveries, either vaginal or cesarean section. The intention of this study was to investigate whether there were any such changes. METHODS: Blood samples were taken on admission to the obstetric ward, first and third day after vaginal delivery (11 patients) or cesarean section (11 patients). Platelet count, hemoglobin concentration and hematocrit was measured for each blood sample. RESULTS: There was no significant change in platelet count after vaginal delivery. Following cesarean section there was a median decrease in platelet count of 12.5% the first postoperative day, and a median increase of 5% the third postoperative day. CONCLUSIONS: Platelet count remains unchanged after uncomplicated vaginal delivery. Shortly following normal pregnancy and uncomplicated cesarean section platelets should be expected to decrease slightly.

Female↗

Improvement of platelet counts in steroid-unresponsive idiopathic immune thrombocytopenic purpura after short-course therapy with recombinant alpha 2b interferon.

In 13 patients with severe steroid-refractory idiopathic immune thrombocytopenia (ITP), a short course of recombinant alpha 2b interferon (IFN), given at a dose of 3 MU for 12 doses, caused a significant increase in platelet count in 11 patients. The rise in platelet count occurred following completion of the short course of IFN in 10 patients and occurred during therapy in one patient. Three patients showed an increase to normal platelet counts within 14 days of discontinuing the drug, eight showed a partial response, with a platelet count increase from 30 to 100 x 10(9)/L, and two patients showed minimal response. One complete responder relapsed at 5 months from initial response, and a further course of alpha 2b IFN caused a second prompt response with a rise of platelet count to supranormal levels. Short-course alpha 2b IFN can be recommended as a therapy for severe ITP. Responses are seen in splenectomized and nonsplenectomized subjects, and thrombocytopenia is not exacerbated during treatment.

Autoimmune Diseases↗

Serum aminotransferase levels and platelet count as predictive factor of fibrosis and cirrhosis in patients with chronic hepatitis C infection.

OBJECTIVE: To assess the ratio of aminotransferases in combination with platelets count as a predictive factor for stages of fibrosis in patients with chronic hepatitis C virus infection. METHODS: A total of 266 patients were evaluated retrospectively who had undergone liver biopsy as a part of their evaluation for the management of chronic hepatitis C infection at Shifa International Hospital from 1998 to 2002. All these patients had complete blood counts and liver function tests including transaminases. The ratio of AST/ALT and platelet count of <150,000 were noted and degree of the fibrosis and cirrhosis on liver biopsies were matched. None of these patients had history of alcohol consumption. The fibrosis stages used were according to METAVIR score. RESULTS: An AST/ALT ratio of >1 and a platelet count of <150,000 had sensitivity of 85.6 and specificity of 90.0 with positive predictive value of 91.2 and negative predictive value of 83.4 for the fibrosis grade-III and IV. An AST/ALT ratio of <1 and a platelet count of >150,000 for grades 0-2, the sensitivity was 87.3, specificity 60.0, PPV 87.3 and NPV 48.0. CONCLUSION: An AST/ALT ratio of >1 in combination with a platelet count of <150,000 can predict advance stage of fibrosis and cirrhosis in patients with chronic hepatitis C infection. In these patients, a liver biopsy may not be necessary.

Adult↗

Cytoplasmic fragments causing spurious platelet counts in hairy cell leukemia: ultrastructural characterization.

A patient with hairy cell leukemia had a spuriously elevated automated platelet count because of cytoplasmic fragments. The cytoplasmic fragments observed with electron microscopy were found in the same fraction as the platelets (platelet-rich plasma). Ultrastructural examination confirmed the hairy cell cytoplasmic origin of these fragments because of their obvious difference from platelet ultrastructure. Cytoplasmic fragments as a cause of spuriously high automated platelet counts should be considered in all cases of hairy cell leukemia. The blood smear can suggest these factitious events and should be used to confirm the platelet count. It is important to validate the automated platelet count even when reported values are within the normal range, since electronic counting may result in a spurious thrombocytosis or a spuriously normal count.

Blood Platelets↗