Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “POLYCYTHEMIA”

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 127 records · Page 7Linked to original sources
PubMed2004

Diagnostic approaches to polycythemia vera in 2004.

Four years have passed since publication of the latest update in clinical criteria for the diagnosis of polycythemia vera. During this time, the first molecular markers for polycythemia vera have been described. They include decreased expression of the thrombopoietin receptor, c-Mpl, and overexpression of the polycythemia rubra vera-1 messenger RNA. These biomarkers, which are not in themselves the causative changes leading to disease development but nonetheless appear intricately linked to the pathological process, may constitute a useful addition to our diagnostic repertoire. This review examines both the currently available clinical criteria and the possible role of biomarkers in the diagnosis of polycythemia vera. From this discussion, a refined set of diagnostic criteria for polycythemia vera is proposed.

Biomarkers↗
PubMed1999

[Clinical characteristics of polycythemia vera in the elderly].

Of 43 elderly patients who were suspected to have polycythemia between October 1990 and July 1998, 12 patients showed an increased red cell volume measured by 51Cr-labeled red blood cells. We analyzed the clinical characteristics of the 12 patients consisted of 7 men and 5 women, with a median age of 71 (range: 57-92). Chief complaints were headaches and dizziness (3 cases), symptoms of other conditions than polycythemia (4 cases). Five patients had no symptoms. Five of 6 patients over 70 years old had no symptoms due to polycythemia. Seven cases (58%) showed splenomegaly and three cases (25%) showed hepatomegaly. Laboratory findings were as follows: WBC 9.7 +/- 3.9 x 10(3)/microliter (mean +/- SD, p < 0.02 vs normal control), Hb 17.9 +/- 4.2 g/dl (p < 0.001), Plt 39.7 +/- 26.0 x 10(4)/microliter, EPO 13.8 +/- 5.2 mU/ml (p < 0.0001), NAP score 258 +/- 114, Vit. B12 1,686 +/- 2,156 pg/ml, arterial O2 saturation more than 92% in all cases. The diagnosis of all cases was polycythemia vera according to the diagnostic criteria of Polycythemia Vera Study Group. Associated conditions included 8 cases of thrombosis (cerebral thrombosis 4, thrombophrebitis 2, myocardial infarction 1, ischemic colitis 1) and 3 cases of malignancy (esophageal cancer 1, breast cancer 1, renal cancer 1), none of which was therapy-related cancer. Six patients (50%) had only phlebotomy, three (25%) only chemotherapy, and three (25%) both phlebotomy and chemotherapy. Patients over 80 years old needed neither intensive nor continuous treatment. Only one patient died due to esophageal cancer at age 89.

Aged↗
PubMed1995

Polycythemia vera: the natural history of 1213 patients followed for 20 years. Gruppo Italiano Studio Policitemia.

OBJECTIVE: To reassess the natural history of polycythemia vera and to obtain reliable estimates of both incidence of thrombosis and survival for use in defining the sample size for therapeutic clinical trials. STUDY DESIGN: Retrospective cohort study of patients with polycythemia who had been followed for 20 years. SETTING: 11 Italian hematology institutions. PATIENTS: 1213 patients with polycythemia vera, which was diagnosed according to criteria established by the Polycythemia Vera Study Group and commonly used in clinical practice. MAIN OUTCOME MEASURES: All-cause mortality, venous and arterial thrombosis, and hematologic and nonhematologic neoplastic disease. Myocardial infarction and stroke were classified as major thrombotic events, and venous and peripheral arterial thrombosis were considered minor thrombotic events. The number of patients who died and the number of those who had major thrombotic events (combined end point) were used as a comprehensive measure of the benefit-risk ratio associated with the use of myelosuppressive agents. RESULTS: 634 fatal and nonfatal arterial and venous thromboses were recorded in 485 patients (41%); 36% of these episodes occurred during follow-up in 230 patients (19%), and 64% occurred either at presentation or before diagnosis. Thrombotic events occurred more frequently in the 2 years preceding diagnosis, suggesting a causal relation between the latent myeloproliferative disorder and the vascular event. The incidence of thrombosis during follow-up was 3.4%/y; older patients or those with a history of thrombosis had a higher risk for thrombosis. Overall mortality was 2.9/100 patients per year; thrombotic events and hematologic or nonhematologic cancers had similar effects on mortality. Patients receiving chemotherapy died three to four times more frequently than those not receiving chemotherapy. The increased risk for cancer in patients receiving myelosuppressive agents was seen approximately 6 years after diagnosis. In addition, the combined end point, computed as the sum of the hardest available events (death, nonfatal myocardial infarction, or stroke), suggests that myelosuppressive agents have an overall unfavorable effect. CONCLUSIONS: Cytoreduction favorably affects the incidence of thrombotic events, but aggressive treatment seems to be associated with increased risk for neoplasm. These results provide a basis for reevaluating the therapeutic strategy in patients with polycythemia vera and for estimating the size of clinical trials aimed at testing new therapeutic approaches.

Adult↗
PubMed1999

Neonatal polycythemia: effects of partial exchange transfusion using fresh frozen plasma, Haemaccel and normal saline.

BACKGROUND: Neonatal polycythemia remains a significant clinical problem in Thailand. Partial exchanges transfusion (PET) with fresh frozen plasma (FFP) has been the mainstay of management for this condition in Thailand. Since FFP is difficult to find in certain areas and can cause concerns of transfusion related diseases, this study was undertaken to investigate the possibility of using plasma substitute and normal saline (NSS) for PET in the newborn infant with polycythemia. OBJECTIVE: 1. To compare the rate and duration of decrease of venous hematocrit (Hct) before and after PET with FFP, Haemaccel and NSS. 2. To compare any complications from using FFP, Haemaccel and NSS such as coagulation defect, electrolytes change, etc. in PET. METHODS AND SUBJECTS: A randomized prospective trial was conducted in Neonatal Unit, Department of Pediatrics, Ramathibodi Hospital. The first phase of study: July 1, 1993 to June 30, 1994: randomized prospective trial using FFP or Haemaccel for PET in 26 newborn infants with polycythemia. The second phase of study: July 1, 1994 to June 30, 1995: consecutive enrollment trial using NSS for PET in 38 consecutive newborn infants with polycythemia. RESULTS: There was significant decrease in Hct in both groups after PET but there was no statistically significant difference in the rate of decrease of Hct. There was no significant difference in biochemical profiles in both groups of infants 24 hours after PET. In the NSS group, there was significant decrease of Hct level after PET. There was no significant change of biochemical profiles and coagulation activity in these patients 24 hours after exchange transfusion. There were 2 patients with complications related to umbilical venous catheter and PET. CONCLUSION: Haemaccel and NSS can be safely used for PET to treat neonatal polycythemia. However, the attending physician should be aware of possible complications related to umbilical venous catheterization and PET.

Exchange Transfusion, Whole Blood↗
PubMed2006

Endothelin-1, vascular endothelial growth factor and systolic pulmonary artery pressure in patients with Chuvash polycythemia.

BACKGROUND AND OBJECTIVES: Endothelin-1 has been associated with development of hypoxia-related pulmonary hypertension and vascular endothelial growth factor (VEGF) with protection from this complication. In Chuvash polycythemia, homozygous germline von Hippel-Lindau (VHL) 598C->T leads to up-regulation during normoxia of hypoxia inducible factor-1a and several hypoxia-controlled genes including erythropoietin and VEGF. We postulated that endothelin-1 and pulmonary artery pressure may be elevated in Chuvash polycythemia. DESIGN AND METHODS: Systolic pulmonary artery blood pressure was estimated by Doppler echocardiography and plasma concentrations of endothelin-1, VEGF and erythropoietin were determined in 14 patients with Chuvash polycythemia and 14 controls. Results. Plasma endothelin-1 (p=0.010), VEGF (p=0.022) and erythropoietin (p<0.0005) concentrations and Doppler-estimated systolic pulmonary artery pressures (p<0.0005) were higher in the patients while systolic systemic blood pressures were lower (p=0.001). Five (36%) patients and no controls had mild pulmonary hypertension defined as systolic pulmonary artery pressure (c) 35 mmHg. Among the patients with Chuvash polycythemia, the trends of association of estimated pulmonary artery pressure with plasma concentrations of endothelin-1 (R = +0.236), VEGF (R = -0.389) and erythropoietin (R = +0.220) were not statistically significant. INTERPRETATIONS AND CONCLUSIONS: Estimated systolic pulmonary artery pressure and plasma concentrations of endothelin-1 and VEGF are increased in patients with Chuvash polycythemia patients. The lack of significant associations of estimated systolic pulmonary artery pressure with plasma endothelin-1 and VEGF levels could conceivably be due to the small sample size. Further studies are indicated, especially in view of the reported efficacy of endothelin-1 receptor blockers in treating hypoxia-associated pulmonary hypertension.

Altitude↗
PubMed1990

Polycythemia in the newborn.

Polycythemia (venous PCV greater than 65%) in neonates is not an infrequent occurrence. Over the last 2 years out of approximately 1500 admissions to the Neonatal Unit, polycythemia was detected in 46 babies (3.06%). Seventeen (36%) of these babies were preterm and 29 (63%) were term. Approximately one third were small for dates while 2 babies (4%) were large for dates. Four of them had been born to mothers with gestational diabetes and 7 were twin deliveries. Severe perinatal asphyxia (5 minute Apgar score less than or equal to 5) was present in 12 cases (26%). Symptoms suggestive of polycythemia included lethargy in 15%, refusal to feed in 13%, respiratory distress in 10%, vomiting in 8% and abdominal distension in 6%. Associated hypoglycemia was seen in 5 cases (10.8%) while twelve babies (26%) had significant jaundice (bilirubin greater than or equal to 12 mg/dl). Twenty eight babies (60.8%) were given a partial plasma exchange transfusion through the umbilical route. There was 6.5% mortality in these 46 babies with polycythemia. Blood letting through a peripheral vein along with a plasma infusion may be a safer alternative to partial plasma exchange transfusion through umbilical route in babies with polycythemia.

Bloodletting↗
PubMed1990

Polycythemia vera and other polycythemic states.

The diagnosis of polycythemia requires an accurate and independent assessment of both plasma volume and red blood cell mass. Patients with an increased red cell mass (absolute polycythemia) may be hypoxic or have an erythropoietin-secreting tumor or space-occupying lesion compressing the kidney. Those with a reduced plasma volume (relative polycythemia) most often are tobacco smokers, are taking diuretic or cardiac medications, or ingest increased quantities of caffeine-containing beverages. On the other hand, polycythemia vera is a systemic disease with multiple complications, which is best diagnosed through a complex of findings as outlined by the Polycythemia Vera Study Group.

Bone Marrow↗
PubMed1988

Cytogenetic studies in polycythemia vera.

A group of 54 patients with the original diagnosis of polycythemia vera were subjected to cytogenetic examination. Six (17.6%) of the 34 cases examined in the period of the advanced phase of the polycythemia vera had a chromosomal change. Thirteen (65%) of the 20 patients undergoing the cytogenetic examination in the period when the polycythemia vera turned into another myeloproliferative disease showed chromosomal aberration. This suggests a relationship between the number of chromosomal changes and the transformation of the disease. No connection between the cytogenetic changes and myelosuppressive cures could be confirmed in our material. The chromosomal change 20q- considered to be the most frequent kind in the polycythemia vera was not discovered until in patients with the polycythemia vera transformed into a different myeloproliferative disease.

Adult↗
PubMed1986

Neonatal polycythemia: frequency of clinical manifestations and other associated findings.

We report the results of a two-part study examining the frequency of symptoms and other findings associated with neonatal polycythemia. In the first part of the investigation, we evaluated the occurrence and features of the disorder in a cohort of 3,768 infants born at our institution that had been screened for the disorder during a 4-year period. Fifty-five infants (1.46%) had neonatal polycythemia. Of these infants, 85% had features associated with the disorder. Frequent signs and symptoms included "feeding problems" (21.8%), plethora (20.0%), lethargy (14.5%), cyanosis (14.5%), respiratory distress (9.1%), jitteriness (7.3%), and hypotonia (7.3%). Other findings included hypoglycemia (40.0%) and hyperbilirubinemia (21.8%). Of the polycythemic infants, 14.5% had no clinical symptoms or associated laboratory abnormalities. In the second portion of the study, we reviewed the features of polycythemia in all infants so diagnosed who were born in United States Army hospitals, worldwide, during a 5-year period. There were 220,050 infants born during this period; 932 (0.42%) were diagnosed as having neonatal polycythemia. Frequent findings were hyperbilirubinemia (33.5%), hypoglycemia (13.0%), and respiratory distress (6.6%). In this large group, only 13 (1.4%) had necrotizing enterocolitis, and nine (1.0%) were thrombocytopenic. Several findings among the 932 infants were unexpected. Six of the infants (only one premature) had intracranial hemorrhages. Additionally, three of the 932 had gonadal dysgenesis and three had cystic fibrosis. We found that premature infants were not less prone to having polycythemia and that the overall frequency of the disorder was less than that which has been previously reported.

Birth Weight↗
PubMed1978

Studies of the mechanism of polycythemia induced in rats by Ni3S2.

Intrarenal injection of 10 mg Ni3S2 elicits polycythemia in rats. This can be attributed either to direct stimulation or to erythropoietin-induced hyperplasia of erythropoietic elements of bone marrow. While studying the mechanism of this experimental model of polycythemia we noted that: (a) extirpation of the injected kidney after the development of the hematologic alterations abolished the polycythemia within 1 month; (b) intravenous, intramuscular or intrahepatic treatment with Ni3S2 was ineffective in producing polycythemia; and (c) there was a modest but statistically significant elevation of plasma erythropoietin levels in rats 2,4 and 8 weeks after injection of Ni3S2, at a time when the hematocrit values were increased. The experiments support the view that Ni3S2 does not directly stimulate erythropoiesis in bone marrow but primarily affects the injected kidney, which in turn (by the continuous liberation of modest amounts of erythropoietin or some hitherto unknown substance) triggers the development of polycythemia.

Animals↗
PubMed1982

Diagnosis of canine primary polycythemia and management with hydroxyurea.

Severe polycythemia was found in 3 dogs with PCV 68% to 70%. Direct RBC mass determinations were increased in all dogs, confirming absolute polycythemia. Cause for secondary polycythemia was not found in any of the dogs; serum erythropoietin concentrations were undetectable, consistent with primary polycythemia. The polycythemia and associated clinical signs were controlled successfully for extended periods (mean, 16.6 months), using phlebotomy followed by oral administration of hydroxyurea in loading and in daily maintenance dosages.

Animals↗
PubMed1995

Pheochromocytoma associated with polycythemia: case report.

Secondary polycythemia has been noted in association with various neoplasms. An erythropoiesis stimulating factor (erythropoietin) has been demonstrated in the fluid or tissues obtained from most of these neoplasms and erythropoietin levels were found to be elevated in the serum and returned to normal after resection of these tumors. Recently, the potential of pheochromocytoma to produce a wide variety of hormones and neurotransmitters such as growth hormone, motilin, ACTH, atrial natriuretic factor (ANF) and others has been shown. Although elevated hematocrit has been observed in association with pheochromocytomas, the occurrence of absolute polycythemia in such cases is very rare. In this report, we describe a patient with a long history of hypertension and cardiac dysrhythmia as well as polycythemia which was secondary to pheochromocytoma. The patient's blood pressure normalized and the polycythemia regressed after resection of the tumor. Increased release of erythropoietin is the most favored explanation for this rare association. Pheochromocytoma should be included in the differential diagnosis of secondary polycythemia.

Adrenal Gland Neoplasms↗
PubMed1994

Post-polycythemia myeloid metaplasia: experience with a large cohort of patients.

The common origin of myeloproliferative disorders can explain the possible evolution of polycythemia vera to post-polycythemia myeloid metaplasia (PPMM). Such a possible event is usually considered linked to the use of myelosuppressive agents in particular 32P. Occasionally, myelofibrosis following essential thrombocythemia has also been described. We report here 19 cases of post-polycythemia myeloid metaplasia out of 214 polycythemia vera patients (8.8%). The majority of these patients received 32P therapy. However, busulfan also seems to have some role in the modification of polycythemia vera. In particular, the association of more than one myelosuppressive agent may favour the evolution of PPMM.

Adult↗
PubMed1993

[Association of polycythemia vera and multiple myeloma. Presentation ofa new case and review of the literature].

We present a patient diagnosed of polycythemia vera who developed a multiple myeloma 13 years after the initial diagnosis of polycythemia vera. Although an unusual finding, another 17 patients with polycythemia and myeloma have been described. In some patients the diagnosis of both diseases was simultaneous but in most cases myeloma developed years after polycythemia vera. Some patients received only venipuncture for treatment of polycythemia vera so the appearance of multiple myeloma could not be explained on the grounds of chemotherapy induced second neoplasm. An explanation for this association is suggested.

Aged↗
PubMedDate not supplied

Polycythemia: from clones to clinic.

Increasing evidence for pathological erythroid clones and availability of additional diagnostic criteria suggest to reconsider the classification of polycythemia, with particular regard to the separation between primary proliferative polycythemia (PPP) or polycythemia vera, and other conditions in which the excessive red cell mass is not due to a myeloproliferative disorder. The characteristics of the abnormal erythropoietic clone in PPP are reviewed, with special reference to the in vitro growth of Epo-independent clones and the response to Epo and other growth factors. Traditional PPP diagnostic criteria are thus integrated with more recent parameters and the clinical features are considered; the main features of idiopathic erythrocytosis (IE) are also reviewed, as well as those of other forms, like familial, secondary and apparent polycythemia. It is pointed out that previously obscure forms are now being elucidated, with the decisive help from molecular biology investigations, allowing the discovery of genetic defects. It is thus becoming apparent that basic science acquisitions, as in the field of erythropoietic initiators (Epo receptor, GATA-1 transcription factor and so on) are eventually helping our understanding of clinical problems in this area, with relevant consequences on diagnosis and treatment of various forms of polycythemia.

Clone Cells↗
PubMed1994

Identification of masked polycythemia vera from patients with idiopathic marked thrombocytosis by endogenous erythroid colony assay.

We used the methylcellulose-culture technique to determine the utility of the erythroid progenitor growth in vitro from nonadherent T-depleted bone marrow and peripheral blood cells in distinguishing polycythemia vera (PV) from essential thrombocythemia. Thirty patients with PV (group A) and 30 patients who presented with idiopathic marked thrombocytosis with platelet count greater than 1,000 x 10(9)/L and a normal or reduced hemoglobin (Hb) level (group B) were studied at initial presentation. Endogenous (erythropoietin-independent) erythroid colonies (EEC) were found in all patients in group A and 13 in group B. The numbers of EEC were comparable between patients in group A and the 13 patients with EEC in group B, 11 of whom with initial Hb levels ranging between 6.4 g/dL and 12.6 g/dL were found to have PV 2 to 45 months after initial evaluation. The number of EEC did not correlate with the time to the progression of polycythemia, whereas myelosuppression delayed the subsequent development of PV. Of the two patients with EEC in group B who did not develop PV, both received chemotherapy soon after presentation, which might preclude the evidence of polycythemia evolution. None of the other patients in group B who did not form EEC developed PV with a median follow-up of 24 months. This study indicates that the assessment of EEC in bone marrow or blood is helpful in early identification of PV or prediction of polycythemia evolution in patients with marked thrombocytosis in whom polycythemia has been initially masked or anemia is present.

Aged↗
PubMed1997

Congenital polycythemia in Chuvashia.

Familial and congenital polycythemia, not due to high oxygen affinity hemoglobin or reduced 2,3-diphosphoglycerate in erythrocytes, is common in the Chuvash population of the Russian Federation. Hundreds of individuals appear to be affected in an autosomal recessive pattern. We studied six polycythemic Chuvash patients <20 years of age from unrelated families and 12 first-degree family members. Hemoglobins were markedly elevated in the index subjects (mean +/- standard deviation [SD] of 22.6 +/- 1.4 g/dL), while platelet and white blood cell counts were normal. Although performed in only three of the index subjects, serum erythropoietin concentrations determined by both radioimmune and functional assays were significantly higher in polycythemic patients compared with first-degree family members with normal hemoglobin concentrations. Southern blot analysis of the Bgl 2 erythropoietin gene polymorphism showed that one polycythemic subject was a heterozygote, suggesting the absence of linkage of polycythemia with the erythropoietin gene, assuming autosomal recessive inheritance. Polymerase chain reaction (PCR) amplification of the GGAA and GA minisatellite polymorphic regions of the erythropoietin receptor gene showed no evidence of linkage of phenotype with this gene. We conclude that Chuvash polycythemia may represent a secondary form of familial and congenital polycythemia of as yet unknown etiology. This condition is the only endemic form of familial and congenital polycythemia described.

Adolescent↗
PubMed1996

Essential thrombocythemia following polycythemia vera: an unusual sequence.

Myeloproliferative disorders (MPD) are prone to modification and evolution during the progression of the disease. While post-polycythemia myeloid metaplasia and chronic myelogenous leukemia following polycythemia vera have been frequently described, no report is available about the evolution of polycythemia vera into essential thrombocythemia. Our case is probably the first report on this occurrence. In the course of a fortuitous observation of electrocardiographic alterations, a diagnosis of polycythemia vera was ruled out in accordance with polycythemia vera study group criteria. At the time of diagnosis, RBC was 6 x 10(12)/L, WBC 15 x 10(9)/L, Ht 59% and platelets 1000 x 10(9)/L. The patient was treated with phlebotomies and radioactive phosphorus achieving a good remission or the disease. Five years later, platelets rose to over 3300 x 10(9)/L without significant modification or RBC, WBC and Ht. The restaging or the disease was consistent for an essential thrombocythemia. In particular, RBC mass was within normal levels. During the last ten years, the patient has been followed recurrently and the blood picture remained stationary, without an increase in the hematocrit but with a platelet count between 658 and 800 x 10(9)/L. We conclude that this report may complete data concerning the evolution of MPD in others.

Aged↗