Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “THROMBOCYTOSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,315 records · Page 73Linked to original sources

Inducible expression of BCR/ABL using human CD34 regulatory elements results in a megakaryocytic myeloproliferative syndrome.

The BCR/ABL fusion protein is found in more than 90% of patients with chronic myeloid leukemia (CML) as well as in a subset of patients with acute B-cell leukemia. We have previously described a transgenic model for an inducible and reversible acute B-cell leukemia caused by p210 BCR/ABL. Here, we describe a new model of an inducible BCR/ABL disease by directing the expression of the oncogene to megakaryocytic progenitor cells within the murine bone marrow using the tetracycline-responsive expression system under the control of human CD34 regulatory elements. The predominant feature was the development of a chronic thrombocytosis. The condition progressed with the development of splenomegaly accompanied by lymphadenopathy in some mice. Affected animals demonstrated a dramatic increase in the number of megakaryocytes in the bone marrow and the spleen. Immunohistochemistry demonstrated that the reporter gene was expressed in hematopoietic stem cells (HSCs), common myeloid progenitor (CMP) cells, as well as in megakaryocytic/erythroid progenitor cells (MEPs). Although these mice did not display the increase in granulopoiesis commonly found in chronic myeloid leukemia (CML), the phenotype closely resembles a myeloproliferative disorder affecting the megakaryocytic lineage observed in some patients with the BCR/ABL P210 translocation.

Animals↗

Effects of pegylated recombinant human megakaryocyte growth and development factor in patients with idiopathic thrombocytopenic purpura.

We conducted a phase 1-2 clinical trial to evaluate the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) in patients with chronic idiopathic thrombocytopenic purpura (ITP) refractory to standard therapy who had platelet counts below 30 x 10(9)/L. Four patients received PEG-rHuMGDF (0.5 microg/kg of body weight per day) by daily intravenous injection for up to 7 days. Administration of PEG-rHuMGDF increased platelet counts in 3 patients. A striking thrombocytosis occurred in 2 patients, whose platelet counts were elevated to more than 700 x 10(9)/L a week after the last administration of PEG-rHuMGDF and returned to baseline levels within 4 to 6 weeks. Before the platelet peak, the percentage of reticulated platelets increased transiently in 3 patients tested, including one patient who had no response. Bleeding episodes decreased after the start of PEG-rHuMGDF therapy. These results suggest that PEG-rHuMGDF might have a clinical benefit in ameliorating thrombocytopenia associated with ITP.

Adult↗

BCR rearrangement-negative chronic myelogenous leukemia revisited.

PURPOSE: To document the characteristics of patients with major breakpoint cluster region (M-bcr) rearrangement-negative chronic myelogenous leukemia (CML). PATIENTS AND METHODS: The hematopathologist, who was blinded to patients' molecular status, reviewed the referral bone marrows and peripheral-blood smears from 26 patients with Philadelphia (Ph) translocation-negative CML who lacked Bcr rearrangement (and other evidence of a Bcr-Abl anomaly) and 14 patients (controls) with chronic-phase Ph-positive CML. Clinical data was ascertained by chart review. RESULTS: Among the 26 M-bcr rearrangement-negative CML patients, three pathologic subtypes emerged: (1) patients indistinguishable from classic CML (n = 9), (2) patients with atypical CML (n = 8), and (3) patients with chronic neutrophilic leukemia (n = 9). Among the 14 patients with Ph-positive CML who were included in the blinded review, 13 were classified as classic CML, and one was classified as atypical CML. The only statistically significant difference between M-bcr rearrangement-negative subgroups was in the proportion of patients having karyotypic abnormalities, an observation common only in patients with atypical CML (P = 0.008). However, the small number of patients in each subgroup limited our ability to differentiate between them. Interferon alfa induced complete hematologic remission in five of 14 patients; four of these remissions lasted more than 5 years. Only one of 26 patients developed blast crisis. The median survival of the 26 patients was 37 months. CONCLUSION: Patients with M-bcr rearrangement-negative CML fall into three morphologic subgroups. Disease evolution does not generally involve blastic transformation. Instead, patients show progressive organomegaly, leukocytosis, anemia, and thrombocytosis. Some patients in each subgroup can respond to interferon alfa.

Adult↗

Overexpression of the polycythemia rubra vera-1 gene in essential thrombocythemia.

PURPOSE: To examine the utility of polycythemia rubra vera-1 (PRV-1)-specific reverse transcriptase polymerase chain reaction (RT-PCR) to discriminate essential thrombocythemia (ET) and polycythemia vera (PV) from secondary thrombocytosis (ST) or secondary erythrocytosis (SE). PATIENTS AND METHODS: We analyzed the expression of PRV-1 in granulocytes isolated from 37 patients with ET, 37 patients with PV, 25 patients with ST, 10 patients with SE, 25 patients with secondary leukocytosis (SL), five patients with chronic myelogenous leukemia (CML), five patients with chronic idiopathic myelofibrosis (IM), five patients with myelodysplastic syndrome (MDS), and 20 normal individuals by PRV-1-specific RT-PCR. In female patients, PRV-1 expression was correlated with clonality analysis as assessed by the human androgen receptor polymorphism assay. RESULTS: PRV-1 was not expressed in granulocytes isolated from normal individuals or from patients with ST, SE, CML, IM, MDS, and inflammatory/infectious SL. On the contrary, all ET patients, 35 of 37 PV patients, and five patients with acute postsurgery and posttraumatic SL overexpressed PRV-1. All the cases with monoclonal hematopoiesis (17 of 21 with ET and 12 of 12 with PV) expressed PRV-1, yet PRV-1 overexpression extended also over the cases of ET showing polyclonal hematopoiesis (four of 20). CONCLUSION: The overexpression of PRV-1 seems to be a useful tool for discriminating ET and PV from ST and SE, thus offering an innovative diagnostic approach on the basis of the detection of positive diagnostic criteria instead of exclusion criteria.

Adult↗

The effects of graded resistance exercise on platelet aggregation and activation.

PURPOSE: The purpose of this study was to examine the effects of resistance exercise with varying intensity but with similar volume on platelet aggregation and activation. METHODS: Thirteen healthy male subjects randomly completed three resistance exercise test trials at an intensity corresponding to 40%, 60%, and 80% of one repetition maximum (1-RM) in which the subjects performed six exercises including upper- and lower-body parts. Venous blood samples were obtained before and immediately after each exercise trial and analyzed for platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), platelet aggregation, and beta-thromboglobulin (B-TG). Plasma volume changes were estimated from hemoglobin and hematocrit readings before and after each exercise trial. RESULTS: Although all exercise trials were followed by a significant (P < 0.05) increase in PLT (thrombocytosis), PCT, and MPV, this rise was not related to the exercise intensity (P > 0.05). Exercise was also followed by a significant increase (P < 0.05) in platelet aggregation, but this only occurred with the high but not with the low concentrations of adenosine diphosphate (ADP). Although ANOVA showed a significant overall increase (P < 0.05) in the concentration of B-TG after exercise, this rise only reached the assigned level of significance (P < 0.05) after 80% exercise trial. CONCLUSION: It was concluded therefore that resistance exercise is followed by an increase in PLT, PCT, and MPV, and this occurred in parallel with an in vivo activation of platelet as manifested by an increase in platelet aggregation and a rise in B-TG.

Adult↗

Chronic granulocytic leukaemia in pregnancy.

In an era when the use of ionizing radiations for the treatment of chronic granulocytic leukaemia has largely been supplanted by therapy with busulphan or other drugs, there still exist situations where irradiation is the preferred method of initial treatment. One such situation is the unusual conjunction of chronic granulocytic leukaemia and pregnancy. Chronic granulocytic leukaemia (CGL) was diagnosed in two young women during early pregnancy as a result of routine blood examinations. Both responded satisfactorily to splenic irradiation with shielding of the uterus. The pregnancies proceeded uneventfully and each was successfully delivered of a normal and subsequently healthy baby. Both mothers later underwent elective splenectomy during a period of satisfactory haematological control: no operative or post-operative complications occurred. Although both patients have shown some thrombocytosis and peripheral blood basophilia since splenectomy, they remain well 58 and 28 months after diagnosis and 30 and 18 months after splenectomy.

Adult↗

Severe hypersensitivity pneumonitis associated with anagrelide.

OBJECTIVE: To report a case of severe life-threatening hypersensitivity pneumonitis temporally associated with the use of anagrelide in a patient with myeloproliferative disorder. CASE SUMMARY: A 60-year-old white woman with chronic myeloid leukemia who had been treated with hydroxyurea for 7 years was offered anagrelide to control thrombocytosis. She developed severe hypersensitivity pneumonitis soon after the drug was initiated and required intubation and mechanical ventilation. A high-resolution computed tomography scan of the chest demonstrated extensive multifocal ground glass attenuation and patchy alveolar consolidation involving both lungs. Bronchoalveolar lavage revealed a preponderance of lymphocytes, suggesting hypersensitivity phenomenon, but was otherwise negative for malignancy and other causes of interstitial pneumonitis. An objective causality assessment revealed that an adverse drug event was probable. Discontinuation of anagrelide and hydroxyurea, and institution of corticosteroid therapy resulted in dramatic improvement. DISCUSSION: To our knowledge, this is the first case report of severe hypersensitivity pneumonitis closely related to anagrelide therapy. Pulmonary infiltrates have rarely been noted in patients treated with anagrelide. Anagrelide does not depress white blood cell production, causes mild anemia, and is devoid of the leukemogenic potential characteristic of radioactive phosphorus and other alkylating agents. Common adverse effects to anagrelide include headache, nausea, diarrhea, peripheral edema, and palpitations. Frank congestive heart failure and cardiomyopathy have occurred in a small number of patients, but severe pulmonary adverse effects have not emerged as a frequent problem. CONCLUSIONS: Vigilance is advised in patients who develop dyspnea while taking anagrelide and hydroxyurea. Healthcare providers need to be aware of the possibility of the development of serious life-threatening hypersensitivity pneumonitis. These patients may benefit from serial chest X-rays, pulmonary function testing, and echocardiography.

Adrenal Cortex Hormones↗

Diagnostic differentiation of essential thrombocythaemia from thrombocythaemias associated with chronic idiopathic myelofibrosis by discriminate analysis of bone marrow features--a clinicopathological study on 272 patients.

Until now diagnosis of essential thrombocythaemia (ET) is generally performed by following the criteria of the Polycythaemia Vera Study Group (PVSG) that only marginally regards morphological features. Bone marrow biopsies were studied from 272 patients with ET in strict accordance with the PVSG guidelines and also from 35 control patients with reactive thrombocytosis. To define morphological features of distinctive impact more accurately, we performed a stepwise discriminant analysis of 16 morphological parameters based on histochemical staining reactions and semiquantitative grading of standardized features. A clear-cut separation into three distinctive histological patterns was accomplished that showed in more than 96% a correct predicted classification. Variables of significant impact included fibre content, quantity and cytological abnormalities of megakaryopoiesis like bulbous (cloud-like) nuclei, degree of nuclear lobulation and presence of giant forms. These changes were not detectable in the control group. The different constellations of histopathological features could be assigned to true ET (98 patients) and false ET, i.e. 136 patients with prefibrotic and 38 patients with early fibrotic chronic idiopathic myelofibrosis (IMF) accompanied by thrombocythaemia. A re-evaluation of clinical findings was in keeping with this classification into three categories that exerted significant differences to develop myelofibrosis during observation time and also different survival patterns. Contrasting IMF true ET is characterized by a pronounced proliferation of the megakaryocyte lineage showing large to giant cells without maturation defects and no relevant increase in reticulin fibres. Discrimination between these entities is warranted, because of a significant difference in presenting haematological data, follow-up and life expectancy.

Bone Marrow Cells↗

Standardization of bone marrow features--does it work in hematopathology for histological discrimination of different disease patterns?

Standardized bone marrow (BM) features determined by semiquantitative scoring are valuable tools for the recognition and easily reproducible interpretation of histological patterns in hematopathology. This procedure may help to characterize various disease entities, but especially to differentiate chronic myeloproliferative disorders (MPDs) with increased platelet counts from reactive thrombocytosis (RTh). A clear-cut separation of these conditions continues to present a major problem in hematology. Therefore MPDs are a most suitable model to test the diagnostic relevance of this procedure. By regarding the literature and based on archive material that involved BM biopsies of 319 patients, a semiquantitative grading of histological parameters was performed. Standardized features were applied for a stepwise discriminant analysis to establish different sets of variables exerting a diagnostic impact. A distinction into five histological patterns was achieved that showed a correctly predicted group membership of about 94 %. These were consistent with the clinicopathological diagnosis of polycythemia vera, essential thrombocythemia (ET), prefibrotic or early fibrotic chronic idiopathic myelofibrosis (CIMF) and finally RTh. Variables of discriminating potency according to their ranking included megakaryopoiesis (maturation defects, nuclear lobulation, naked and bulbous nuclei, small and giant size), reticulin fibers, erythro- and granulopoiesis (left shifting and quantity) and cellularity. These findings are in keeping with the assumption that characteristic patterns of BM histopathology can be assigned to different subtypes of MDPs mimicking ET. Discrimination between ET and especially early stage CIMF with thrombocythemia is warranted because of significant implications concerning therapeutic strategies, follow-up examinations and survival. Regarding these results, a schematic procedure is proposed to be used for daily routine diagnosis concerning the discrimination of MPDs.

Bone Marrow↗

Natural history of asplenism in APECED--patient report.

Only a few reports on patients with hypo/ asplenism associated with APECED have been published, yet hyposplenism has been found in approximately half of the studied patients. The 7-year follow-up in our only patient with APECED revealed a decrease of spleen size from normal to half-size by ultrasound and CT examinations. Scintigraphy of the liver and spleen demonstrated a progressively diminishing splenic uptake of the tracer from low to complete absence. Peripheral blood smears revealed permanent thrombocytosis with the presence of Howell-Jolly bodies when functional asplenism was reached. The cause of autoimmunization and hyposplenism in APECED is unknown. We hypothesize that hyposplenism depends primarily on local AIRE gene dysfunction in the spleen, and secondarily on an AIRE gene-mediated autoagressive process. In our opinion, hypo/asplenism in APECED disease might not be noticed in patients with APECED if not directly examined. Thus we emphasize the necessity of searching for hyposplenism in all patients with APECED, and recommend scintigraphy.

Autoantibodies↗

Major hematological diseases associated with cleft lip and palate.

OBJECTIVE: Cleft lip and palate is among the most common congenital anomalies. Its association with major blood disorders has rarely been reported. The purpose of this study was to report two patients who had major blood diseases associated with cleft lip and palate. PATIENTS AND RESULTS: From June 1995 to December 1997, there were 2700 patients with cleft lip, cleft palate, or both who received treatment at Chang Gung Memorial Hospital. Two of them were found to have major hematological disorders. In both cases, the disorder was detected by preoperative blood cell counts and white cell differentiation. Case 1 was a 21-year-old woman patient with repaired right cleft lip. She was admitted for alveolar bone grafting and closure of oronasal fistula. Abnormal presentation of blast cells was found, and subsequent bone marrow study confirmed acute lymphocytic leukemia. Case 2 was a 26-year-old man with left secondary cleft lip nasal deformity scheduled to receive staged reconstructive operations. An elevated platelet count was found and subsequently confirmed to represent essential thrombocytosis. In both cases, reconstructive operations for the cleft-related deformities were performed. CONCLUSIONS: Association of major hematological disorders and cleft lip, palate, or both is rare and is reported herein.

Adult↗

PTHrP-producing tumor: squamous cell carcinoma of the liver accompanied by humoral hypercalcemia of malignancy, increased IL-6 and leukocytosis.

A 77-year-old man was admitted to our hospital showing symptoms of general fatigue and appetite loss. He had leukocytosis, thrombocytosis and hypercalcemia with elevated serum levels of parathyroid hormone related peptide (PTHrP) and interleukin-6 (IL-6). An increase in tumor markers SCC and CYFURA21-1 was observed. The liver contained a huge tumor, which was proved to be PTHrP producing squamous cell carcinoma by immuno-histochemical analysis. Since the tumor did not express IL-6, it was assumed to be induced by PTHrP in osteoblasts. This is the first report of PTHrP producing squamous cell carcinoma of the liver.

Aged↗

Thrombopoietin-producing hepatocellular carcinoma.

A 66-year-old man with hepatocellular carcinoma (HCC) showed marked thrombocytosis (110.7 x 10(4)/microl). Bone marrow (BM) aspirates demonstrated an increase of mature megakaryocytes (MgK). The serum thrombopoietin (TPO) level was increased to about 100-fold that of the normal level in the terminal stage. However, the platelet count gradually decreased to 13.5 x 10(4)/microl. The autopsy specimen revealed normoplastic BM with decreased MgK, mainly consisting of the immature type, and it was negative for tumor cells. Liver specimen showed markedly fatty metamorphosis. Immunohistochemical staining of TPO demonstrated that hepatocytes were weakly stained and HCC cells strongly stained, suggesting TPO-producing HCC.

Aged↗

Effect of platelet count on serum and plasma potassium: evaluation using database information from two hospitals.

The availability of retrospective data from potassium (K+) analyses from two hospitals, one using serum and the other plasma for electrolyte measurements, offered us the possibility to investigate the effect of blood platelet count on serum and plasma K+ concentrations. A weak correlation between plasma K+ and platelet count was observed. The in vitro increase of serum K+ in proportion to the platelet count has clinical significance in conditions, where it may impede the detection of an underlying true K+ disorder. Nomograms and correction factors, based on the correlation between platelet count and serum K+, have been suggested also in some recent reports. In the present study unselected routine patient data was used as source data. The effect of platelet count on the concentration of K+ in serum was lower than reported in previous studies, as indicated by the regression analysis. An increase of 1000 x 10(9)/l in the blood platelet count would cause an increase of about 0.7 mmol/l in the serum K+ concentration (p < 0.0001, r = 0.155). The weak correlation between platelet count and serum K+ does not support the application of platelet-count-based correction of serum K+ level in thrombocytosis. The laboratory should notify the clinician of the significance of the in vitro increase of K+ caused by increased platelet count. K+ should be measured from plasma in such cases.

Artifacts↗

Haematologic findings in patients with renal carcinoma.

Haemoglobin concentration and leukocyte and platelet counts were studied in 122 patients with renal carcinoma, 104 of whom subsequently underwent nephrectomy. In 61 of the operable patients the tumour was located within the renal capsule (group I) and in the other 43 it had invaded the perinephric tissues (group II). Eleven of the group II patients also had distant metastases in one or two sites. Multiple distant metastases precluded renal surgery in 18 patients (group III). Normochromic anaemia (haemoglobin less than 120 micrograms/l) was found in 17% and leukocytosis (greater than 8 x 10(9)/l) in 25% of the group I patients. The corresponding frequencies for group III were 72 and 67%. Severe anaemia was found in patients with localized tumours as well as in patients with extensive metastases. Thrombocytosis (400-800 x 10(9)/l) occurred in less than 20% of the patients in groups I and II, but in 42% in group III. Thrombocytopenia (less than 200 x 10(9)/l), on the other hand, which was present in 31% of the group I patients, was less common in those with metastasizing tumours. Haematologic anomalies in renal carcinoma suggest either bone-marrow metastases of tumour-induced mechanisms such as production of erythropoietin or thrombopoietin and phagocytic and chemotactic effects of tumour cells or auto-immune processes. When uncorrected by nephrectomy in patients without signs of metastases, such haematologic findings suggest concomitant blood disorders.

Adult↗

Platelet function in rheumatoid arthritis.

Platelet function tests were evaluated in 20 patients with rheumatoid arthritis (RA), 9 of whom displayed thrombocytosis (greater than 400,000 platelets/microliter). Most patients had an enhanced sensitivity to collagen and epinephrine induced aggregation, as compared with a reference group. In contrast, malondialdehyde (MDA) production, an index of platelet arachidonic acid metabolism, was in the normal range for all the patients except 3, who were LE phenomenon positive. The hypersensitivity of platelets to aggregating stimuli was particularly marked in thrombocytotic patients, who also showed the most striking biochemical and clinical abnormality. These findings indicate the crucial role of platelets in the development and self-sustaining of RA.

Adult↗

Acute leukemia with structural rearrangements of chromosome 3.

Cytogenetic investigations have distinguished at least 3 distinct clinical-cytogenetic syndromes of hematopoietic malignancy with structural rearrangement of 3q. The majority of cases have breakpoints at both 3q21 and 3q26, frequently associated with monosomy 7, abnormal thrombopoiesis, and adverse outcome. Cases with only one of these breakpoints may have milder features of the syndrome. A subgroup with t(3q;5q) occurs in younger patients, occasionally with megakaryocytic dysplasia but rarely having thrombocytosis. The t(3;21) is encountered in secondary leukemias or after chemotherapy of myeloproliferative disorders. The genetic deregulations associated with each of these syndromes involve distinct genes on 3q. The majority of cases of acute leukemias with 3q rearrangements have a poor prognosis and do not respond to current modes of therapy.

Acute Disease↗

Induction of megakaryocytic colony-stimulating activity in mouse skin by inflammatory agents and tumor promoters.

The production of megakaryocytic colony-stimulating activity (MEG-CSA) was assayed in acetic acid extracts of skin from mice topically treated with inflammatory and tumor-promoting agents. A rapid induction of MEG-CSA was found in skin treated both with phorbol 12-myristate 13-acetate (PMA), a strong tumor promoter, and with mezerein, a weak tumor promoter, but no induction was found in untreated skin. The time course of induction of MEG-CSA following treatment of skin with PMA or mezerein was very similar to that previously demonstrated for the induction of granulocyte-macrophage colony-stimulating activity in mouse skin by these agents. The induced MEG-CSA was found in both the epidermis and the dermis. Pretreatment of the skin with beta-methasone abrogated the MEG-CSA induction. The cell number response curve suggests that the MEG-CSA acts directly on the progenitor cells of the megakaryocyte colonies. That topical administration of diterpene esters results in the rapid, local induction of MEG-CSA which can be blocked by beta-methasone pretreatment suggests a mechanism for the thrombocytosis associated with some inflammatory states. The indirect action in which diterpene esters induce in certain cells the production or release of growth regulatory factors for other cell types may also aid in understanding their carcinogenic properties.

Animals↗