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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Splenic erythropoiesis was demonstrated by surface counting of 59Fe in 129 of 1,350 ferrokinetic studies performed over a 15 year period. These 129 studies were carried out in 108 patients, including 40 with chronic myelogenous leukemia (CML), 24 with agnogenic myeloid metaplasia (AMM), 18 with polycythemia vera (PV), six with a myelodysplastic syndrome, five with acute leukemia, three with prostate or breast carcinoma, two each with aplastic anemia or Hodgkin's disease, and one each with idiopathic thrombocythemia, multiple myeloma, chronic renal failure, or treated hypopituitarism. Splenomegaly was present in 83% of the studies and hepatomegaly in 72%. Grade II-III myelofibrosis was demonstrated in 62% of the cases. Hepatic erythropoiesis was present in 77% of the studies (only 38% in PV), and marrow erythropoiesis was undetectable in 33%. Total erythropoiesis was about twice normal (range 0.2 to 8 times normal) but was ineffective to varying degrees in 86% of the studies. Relationships between organomegaly, myelofibrosis, and extramedullary erythropoiesis, as well as differences among clinical disorders, are discussed. Differences observed between CML in chronic or blastic phase suggested that the erythroid cell line was involved in the proliferative process. It is concluded that splenic erythropoiesis 1) is encountered in a variety of clinical conditions; 2) is not necessarily associated with splenomegaly or myelofibrosis, even in the myeloproliferative disorders; 3) is part of a predominantly extramedullary (in the liver as well as in the spleen), expanded, and largely inefficient total erythropoiesis; and 4) can be evaluated in a semiquantitative manner by surface counting.
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PMID:Ferrokinetic study of splenic erythropoiesis: relationships among clinical diagnosis, myelofibrosis, splenomegaly, and extramedullary erythropoiesis. 275 9

A new anti-K562 cell monoclonal antibody, RTF8X, a cytotoxic IgM, recognized a surface antigen on erythroblasts from patients with erythroleukemia and polycythemia vera. RTF8X, which is highly specific to K562 cells, did not react with the other 14 hematopoietic cell lines and the seven nonhematopoietic cell lines. RTF8X antigen was not detected in normal peripheral blood, but was found in less than 1% of normal marrow cells. RTF8X did not inhibit in vitro colony formation of CFU-E and BFU-E in a complement-dependent cytotoxicity assay. Cell-sorting analysis showed that, morphologically, the RTF8X-positive marrow cells from the patients and normal volunteers contained more than 60% erythroblasts and that CFU-E and BFU-E were not demonstrated in cells with RTF8X antigen. Enzyme treatment suggested that RTF8X antigen was a sialoglycolipid. These results indicate that RTF8X may recognize the surface antigen found increasingly in association with tumors of erythroid lineage. RTF8X should be useful for studies of erythroid differentiation and proliferation in patients.
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PMID:Anti-K562 cell monoclonal antibody RTF8X recognizes tumor-associated antigen of erythroid lineage. 305 24

Classification and differential diagnosis of erythroid neoplasias still are a matter of discussion. Eleven cases of primary acute erythremia were diagnosed between 1981 and 1984 at the Institute of Pathology, University of Kiel. Erythremia represented 0.5% of all hematological diagnoses and 1.0% of the myeloproliferative disorders. The male-to-female ratio was 1:1. Incidence peaked in the 7th decade. Evaluation of clinical data, of cytological and histological findings in blood and bone marrow, and of occasional immunophenotyping of blast cells (anti-glycophorin A+) revealed two variants of acute erythremia: a first, blastic one and a second, more differentiated form. Acute erythremia must be strictly distinguished from mixed erythroid/myeloid erythroleukemia and from secondary erythroid neoplasias, especially the erythremic 'blast crisis' of chronic myeloid leukemia or polycythemia vera rubra. Distinguishing the myelodysplastic variant of sideroblastic anemia from anerythremic acute erythremia can be extremely difficult. We discuss the differential diagnosis and classification of erythroid neoplasias based upon reproducible hematological criteria to facilitate the gathering and comparison of epidemiological and clinical data on these rare malignancies.
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PMID:Hematopathological features of acute erythremia (morbus Di Guglielmo). A contribution to the classification and differential diagnosis of erythroid neoplasias. 311 28

Primary polycythaemia (PP), idiopathic myelofibrosis (MF), essential thrombocythaemia (ET) and chronic granulocytic or myeloid leukaemia (CGL) are clonal disorders of the pluripotent haemopoietic stem cells. We have studied granulocyte, megakaryocyte and erythroid progenitors from the peripheral blood of 7 patients with PP, 9 with ET, 19 with MF and 6 with CGL in order to characterise similarities and differences at the committed progenitor cell level. Spontaneous megakaryocytic and erythrocytic growth was characteristic of MF, PP and ET but was not seen in CGL. Circulating erythroid (BFU-E) and granulocyte/macrophage (CFU-GM) progenitors were markedly increased in MF and CGL, less raised in ET and closest to normal in PP. Erythropoietin-independent erythroid bursts (EIBFU-E) grew from the blood of patients with MF, PP and ET but spontaneous growth of megakaryocytes occurred in only MF and ET. These results suggest a progression of increasing abnormality from PP, where EIBFU-E occurred with relatively normal numbers of circulating progenitors, to ET where both EIBFU-E and megakaryocyte precursors regularly occur with elevated numbers of progenitors, to MF where spontaneous BFU-E, CFU-Mk and CFU-GM occur at high levels.
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PMID:Primary polycythaemia, essential thrombocythaemia and myelofibrosis--three facets of a single disease process? 312 58

Marrow cells from seven untreated patients with polycythemia vera (PV) were used to initiate standard single inoculum long-term marrow cultures. The numbers, erythropoietin independence, and cycling behavior of all detectable classes of erythroid, granulopoietic, and multilineage progenitors were then evaluated and the results obtained compared with preculture values. Time course studies showed that the long-term marrow culture system supports the continuous proliferation of primitive neoplastic progenitor cells from PV patients for many weeks. However, these progenitors fail to respond to signals from the adherent layer that return their counterparts in normal long-term marrow cultures to a quiescent state 5-7 d after each medium change. This abnormal cycling behavior of PV cells in the long-term culture system appears to mimic that operative in vivo, where primitive hemopoietic progenitors are also in a continuous state of turnover, in contrast to similar primitive progenitor compartments in normal individuals, which are quiescent. The long-term marrow culture system thus offers new possibilities for the further analysis of abnormal cellular and molecular mechanisms underlying clonal expansion at the stem cell level in PV.
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PMID:Unregulated proliferation of primitive neoplastic progenitor cells in long-term polycythemia vera marrow cultures. 333 45

An analysis of the results of determination of erythropoietin in the blood plasma of patients with polycythemia vera and data on the kinetics of erythroid cell proliferation led to a conclusion that erythrocytapheresis more than bloodletting stimulated the production of erythropoietin and the cell proliferative potential. Activation of regenerative processes probably determined by deinhibition of the normal clone of bone marrow erythroid cells, can account for the mechanism of a therapeutic effect of erythrocytapheresis in patients with polycythemia vera.
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PMID:[Erythron in patients with polycythemia vera during treatment by erythrocytapheresis and bloodletting]. 362 98

The definite differential diagnosis between spurious polycythemia (SP) and pure erythrocytosis (PE) was tested. Serum erythropoietin (EPO) levels in 6 patients with PE were 12.8 +/- 3.7 mU/ml and were significantly lower than those of both 19 normal controls (28.5 +/- 15.0 mU/ml) and 9 patients with SP (21.3 +/- 10.2 mU/ml). Three of 11 patients with SP and 1 of 3 patients with PE had significantly higher marrow erythroid progenitor cells (CFU-Es) than those of the normal controls. Spontaneous CFU-E growth (CFU-E growth in the absence of added EPO) was found in 4 of 11 patients with SP, 1 of 3 patients with PE, and all patients with polycythemia vera. However, the number of spontaneous CFU-E was low in SP and PE. The measurements of serum EPO levels and CFU-E growth did not provide differentiation between PE and SP. Even if some patients, whose total red cell volumes are either higher than 12.5% above the mean predicted values or their CFU-E growth is great, are diagnosed as SP, consideration should be made that they might, in fact, have PE.
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PMID:Differential polycythemia: a comparative study between spurious polycythemia and pure erythrocytosis. 368 23

The diagnostic value in polycythemia of the presence of endogenous erythroid colonies derived from bone marrow cells (EECs) was assessed in a prospective study on 108 patients referred for polycythemia (Hb greater than g/dL in men, greater than 16 g/dL in women) with normal plasma volume by comparison with the standard criteria, the bone marrow grade, and the serum erythropoietin (Epo) level. Total red cell volume (TRCV) was high (greater than 36 mL/kg in men, 32 mL/kg in women) in 87 cases (group A) and slightly increased in 21 cases (group B). Standard criteria were applicable in 63 of 108 cases (57%); 46 were PV and 17 were secondary polycythemia (SP). Standard criteria were nonapplicable in 45 cases. EECs were present in 65 cases (60%) with a ratio of EEC/Epo-stimulated colonies of 39.5% +/- 18% (extremes 10% to 80%). EECs were noted in 43 of 46 polycythemia vera (PV) and 0 of 17 SP. Among the 45 unclassified cases, EECs were noted in 22: 18 of 29 cases from group A (10 with 2 major and 1 minor criteria; 8 with 2 major criteria) and 4 of 16 cases from group B (with variable standard criteria, 2 belonging to a PV family). In group A, there was a positive significant correlation between EECs and the presence of two major and 1 minor criteria (P less than .0001). In group B, there was a positive significant correlation between EECs and the presence of at least 1 major criterion and 2 minor criteria or a family background (P less than .0001). The unclassified polycythemias with EECs in the bone marrow are characterized by a bone marrow grade and a mean serum Epo level not different from that of patients with PV and an active course of the disease. The unclassified polycythemias without EECs in the bone marrow are a heterogeneous group corresponding in some cases to SPs of unknown origin (slightly increased bone marrow grade and/or high serum Epo level), and in others cases to spurious polycythemias (normal bone marrow grade and/or normal Epo level). In conclusion, EECs were of great value in differentiating PV from SP (P less than .001), and in allowing the diagnosis of PV in the absence of all the standard criteria even when TRCV was slightly increased. In our study, EEC improved the classification of polycythemia by 22%. The recommended diagnostic steps for the evaluation of polycythemia must be reconsidered.
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PMID:A prospective study of the value of bone marrow erythroid progenitor cultures in polycythemia. 376 35

The mechanism of polycythemia associated with the Budd-Chiari syndrome is unknown. Erythropoiesis in 10 patients with Budd-Chiari syndrome was studied in an attempt to distinguish prior unrecognized polycythemia vera from secondary polycythemia. Serum erythropoietin was assayed using a mouse fetal liver erythroblast assay. High concentrations of serum erythropoietin were observed in 6 of 7 patients with acute primary Budd-Chiari syndrome. Levels were normal in four patients who were investigated during the chronic phase and were increased in one with persisting polycythemia. In one patient, erythropoietin concentration in the hepatic vein was twice the level measured in peripheral, caval and renal venous blood. Bone marrow erythroid progenitors developed in vitro in the absence of exogenous erythropoietin in all polycythemia vera cases studied in acute and chronic phases, whether polycythemia persisted or not. These findings indicate that hepatic erythropoietin production occurs in the acute phase of Budd-Chiari syndrome and suggest that, in some cases of Budd Chiari syndrome, polycythemia which resolves after the acute phase may be secondary to liver disease.
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PMID:Polycythemia and the Budd-Chiari syndrome: study of serum erythropoietin and bone marrow erythroid progenitors. 402 96

The author provides data pertinent to the modern classification of erythrocytosis, which rests on the pathogenetic principle. The difference in the pathogenesis of erythremia and secondary erythrocytoses was proved with the help of an erythroid culture and by examination of erythropoietins, which can be thus used for diagnostic purposes. Analysis of so-called "pure" erythrocytosis has shown that this term implies different patterns of erythrocytosis from the standpoint of the pathogenesis: erythremia, secondary erythrocytoses that are difficult to diagnose, and hereditary erythrocytosis associated with erythropoietin hyperproduction. There is no evidence for the existence of the "pure" erythroid leukemia and thus the author doubts this disease entity. Analysing the different patterns of secondary absolute erythrocytosis the author discusses specific problems of their pathogenesis. Attention is paid to erythrocytosis of a tobacco smoker, to the role of obesity and concomitant action of some factors on the development of hypoxic erythrocytosis. The data are presented on the new types of erythrocytosis, on the post-transplantation one, in particular, which occurs after kidney transplantation, and finally on erythrocytosis that develops occasionally in patients on hemodialysis. Attention is paid as well to relative erythrocytoses, risk factor in the development of thrombotic complications. The problems of etiologically and pathogenetically valid therapy of secondary erythrocytoses are reviewed.
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PMID:[Secondary erythrocytoses]. 404 68


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