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

To determine parameters of distinctive value in polycythemia rubra vera (PV) versus secondary polycythemias (SP), a clinicopathological study was performed on 199 patients. These presented with a borderline to marked elevation of the hemoglobin level (> 18 g/dl in men and > 16 g/dl in women). Evaluations of clinical features and bone marrow histopathology were carried out independently. According to the results derived from laboratory data and representative pretreatment trephine biopsies, three groups of patients emerged: group I presenting with the concordant clinical and morphological findings of early to manifest PV (136 patients), group II consisting of 55 patients with the congruent signs and symptoms of SP mostly caused by various chronic bronchopulmonal disorders, and finally eight patients (group III) with divergent findings. Between group I and II patients (PV versus SP), a number of clinical parameters proved to be significantly different. With the exception, of the red cell mass, platelet count, leukocyte alkaline phosphatase, LDH, spleen size, and the erythropoietin level had a significantly discriminating impact. Morphological features of distinctive value consisted of a set of specific lesions. Contrasting SP with an only borderline to slight increase in cellularity associated with a moderate enlargement of the erythroblastic islets, PV was always characterized by a significant increase in hematopoiesis, revealing a trilinear proliferation (panmyelosis). Megakaryopoiesis was strikingly different in PV as compared to SP by displaying clustering and a pleomorphous appearance. i.e., very small and giant megakaryocytes with staghorn-like nuclei were neighboring each other. Moreover, conspicuous alterations of the interstitial compartment were recognizable in SP. These consisted of deposits of cell debris in histiocytic reticular cells, iron-laden macrophages, and a plasmacytosis, implying an inflammatory reaction. These changes were only very rarely observed in PV, as opposed to a minimal to slight increase in reticulin fibers in about 12% of patients. In conclusion, a more elaborate evaluation of bone marrow features resulted in a set of diagnostic criteria with discriminating capacity that should be considered in prospective clinical trials.
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PMID:Polycythemia rubra vera versus secondary polycythemias. A clinicopathological evaluation of distinctive features in 199 patients. 1126 21

X-radiation remains the treatment of choice in most cases of leukemia and lymphoma, but new agents are playing an increasing role in therapy. Radioactive phosphorus does not produce radiation sickness and results with it are comparable to those of x-ray therapy in chronic leukemia. Urethane and nitrogen mustard may produce remissions in patients with chronic leukemia who have become resistant to radiation. Triethylene melamine may be administered orally with nitrogen mustard-like effects and is undergoing further trial. Aminopterin, ACTH and cortisone often cause short remissions in acute leukemia. Urethane is the best treatment available for multiple myeloma. Polycythemia vera is well controlled by radioactive phosphorus combined with venesection. Nitrogen mustard is often effective and triethylene melamine shows promise in Hodgkin's disease. Antianemic substances such as iron and liver extract are of no value in the treatment of anemia caused by leukemia, lymphoma and myeloma.
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PMID:New therapy for leukemia, polycythemia, and lymphoma. 1301 1

The criteria of the Polycythemia Vera Study Group (PVSG), although acknowledged as the gold standard to establish the diagnosis of polycythemia vera (PV), do not regard bone marrow (BM) histopathology. Arguments include the existence of sufficient objective markers of disease and the lack of independently performed morphological studies or standardized criteria. The aim of this review is to evaluate morphological characteristics of erythrocytosis and to determine whether distinctive patterns of histopathology exist. A review of the pertinent literature and evaluation of 334 patients from our files with a borderline to marked increase in hemoglobin was performed. In extension to former descriptions of BM features by the PVSG, a tri-lineage myeloproliferation (panmyelosis) with a pleomorphous appearance of megakaryopoiesis revealed that, besides increase in size, there was a lack of gross cytological anomalies. Differentiation from secondary polycythemia (SP) was accomplished by regarding these features and the conspicuously expressed stromal changes (plasmacytosis, eosinophils, cell debris and iron deposits). In about 96% of this cohort a clear-cut separation from SP was achieved, even in the initial (latent) stages. When accompanied by an elevated platelet count, these precursor stages may clinically mimick essential thrombocythemia because they are not recognized by the conventional criteria. Advanced stages (spent phases) of PV were consistent with an increased left-shifted granulocytic proliferation, accompanied by reduction of erythroid precursors and progressive myelofibrosis (post-polycythemic myeloid metaplasia). Finally, an increase in dysplastic changes and immaturity signalled a transition into blastic crisis. In conclusion, PV is characterized by a distinctive pattern of histopathology that has been gained in an independent and blind fashion and therefore, dissolves arguments about failing specificity.
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PMID:Diagnostic impact of bone marrow histopathology in polycythemia vera (PV). 1557 48

Chronic Neutrophilic Leukemia (CNL) is a rare myeloproliferative disorder characterized by a persistent increase of mature peripheral neutrophils, myeloid hyperplasia in bone marrow, hepatosplenomegaly, elevated neutrophil alkaline phosphatase (NAP) and absence of Philadelphia chromosome, with no evidence of infection or malignancy sufficient to mimic a leukemoid reaction. CNL has been associated with multiple myelomas in many reported cases, but transition of Polycythemia Vera (PV) to CNL is very rare. An 81-year-old female patient, who had undergone intermittent phlebotomy following the diagnosis of PV 8 years previously, was admitted to our hospital due to lower back pain. A physical examination showed a splenomegaly 2 cm below the costal margin, with tenderness of the thoracic and lumbar spine area. A peripheral blood examination showed a WBC count of 91,800/microL (neutrophil 88%) with a rare immature form, hemoglobin of 9.1 g/dL and a platelet count of 1,661,000/microL. Her NAP score was 58. The bone marrow examination showed 95% cellularity, with an M:E ratio of 10:1, increased megakaryocytes with normal morphology and the absence of myelofibrosis. Chromosomal studies showed no Philadelphia chromosome. A radiological examination showed compression fractures of the vertebrae and spinal cord compression. No underlying disease causing a leukemoid reaction was detected. With iron replacement, the hemoglobin level failed to increase over 12 g/dL. Therefore, it was concluded to be a transition of PV to CNL. After administration of hydroxyurea and vertebroplasty, the symptom improved and the WBC count was sustained below 40,000/microL.
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PMID:A case of transition of polycythemia vera to chronic neutrophilic leukemia. 1568 21

A literature review reports increased erythrocyte indices [hemoglobin concentration, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin (MCH), MCH concentration] in subjects with hereditary hemochromatosis (HH). We, therefore, screened 52 consecutive patients with polycythemia vera for 12 HH gene mutations, comparing iron status and red cell parameters between patients positive or negative for HH gene mutations. Our results support the evidence that there is no association between these two conditions.
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PMID:Analysis of hemochromatosis gene mutations in 52 consecutive patients with polycythemia vera. 1576 83

Controversy continues to persist about the role of histopathology regarding diagnosis of polycythemia vera (PV). For this reason, a clinicopathological study was performed on 334 patients presenting with a sustained borderline to marked erythrocytosis (hemoglobin >17 g/dl in men and >15 g/dl in women). The aim was to elucidate the discriminating impact of bone marrow biopsy examinations in an independent fashion from laboratory parameters. According to morphological findings based on a semiquantitative evaluation of standardized features, cellularity, megakaryocytes (quantity, size, pleomorphous aspect, clustering, nuclear lobulation), eosinophils, cellular debris, perivascular plasmacytosis and iron-laden macrophages exerted a distinctive value. Comparison with clinical data and follow-up revealed that in only 13 patients (4%), histopathology failed to differentiate clearly between PV (208 patients) and secondary polycythemias (113 patients). In conclusion, certain sets of morphological parameters allow a distinction between autonomous and reactive polycythemias and therefore enhance significantly diagnostic validity.
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PMID:Bone marrow features of diagnostic impact in erythrocytosis. 1580 15

The diagnostic criteria of the Polycythemia Vera Study Group (PVSG) do not include bone marrow (BM) examinations. The aim of this review is to elucidate whether distinctive patterns of histopathology exist which discriminate reactive (secondary polycythemia) from autonomous (polycythemia vera) erythrocytosis. When accompanied by an elevated platelet count, the initial stages of PV may clinically mimic essential thrombocythemia because they are not recognized by the conventional diagnostic criteria. Our data are derived from previous studies and evaluations of 362 patients with a borderline to marked increase in hemoglobin. PV revealed a trilineage myeloproliferation (panmyelosis) with a pleomorphous appearance (ie, differences in size) of loosely clustered megakaryocytes that failed to show gross cytological anomalies. Distinction from SP was accomplished by regarding megakaryopoiesis and the stromal changes (perivascular plasmacytosis, eosinophils, cell debris, and iron deposits). Discriminant analysis of standardized BM features, based on semiquantitative evaluation, yielded a sensitivity of 96% concerning the clear-cut separation of PV from SP.
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PMID:Diagnosis of polycythemia vera based on bone marrow pathology. 1586 75

The authors describe a 19 year old male with an isolated but absolute erythrocytosis with iron deficiency without evidence for polycythemia vera as well as another causes of erythrocytosis. The polycythemia was due to a recently described von Hippel-Lindau (VHL) mutation. By stopping iron therapy there was no more requirements for phlebotomy in this patient.
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PMID:Clinical presentation of a patient with congenital polycythemia. 1661 1

Iron(II)-phenylpyruvate complexes of tetradentate tris(6-methyl-2-pyridylmethyl)amine (6-Me3-TPA) and tridentate benzyl bis(2-quinolinylmethyl)amine (Bn-BQA) were prepared to gain insight into C-C bond cleavage catalyzed by dioxygenase enzymes. The complexes we have prepared and characterized are [Fe(6-Me3-tpa)(prv)][BPh4] (1), [Fe2(6-Me3-tpa)2(pp)][(BPh4)2] (2), and [Fe2(6-Me3-tpa)2(2'-NO2-pp)][(BPh4)2] (3), [Fe(6-Me3-tpa)(pp-Me)][BPh4] (4), [Fe(6-Me3-tpa)(CN-pp-Et)][BPh4] (5), and [Fe(Bn-bqa)(pp)] (8), in which PRV is pyruvate, PP is the enolate form of phenylpyruvate, 2'-NO2-PP is the enolate form of 2'-nitrophenylpyruvate, PP-Me is the enolate form of methyl phenylpyruvate, and CN-PP-Et is the enolate form of ethyl-3-cyanophenylpyruvate. The structures of mononuclear complexes 1 and 5 were determined by single-crystal X-ray diffraction. Both the PRV ligand in 1 and the CN-PP-Et ligand in 5 bind to the iron(II) center in a bidentate manner and form 5-membered chelate rings, but the alpha-keto moiety is in the enolate form in 5 with concomitant loss of a C-H(beta) proton. The PP ligands of 2, 3, 4, and 8 react with dioxygen to form benzaldehyde and oxalate products, which indicates that the C2-C3 PP bond is cleaved, in contrast to cleavage of the C1-C2 bond previously observed for complexes that do not contain alpha-ketocarboxylate ligands in the enolate form. These reactions serve as models for metal-containing dioxygenase enzymes that catalyze the cleavage of aliphatic C-C bonds.
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PMID:Iron-catalyzed C2-C3 bond cleavage of phenylpyruvate with O2: insight into aliphatic C-C bond-cleaving dioxygenases. 1746 86

Secondary erythrocytosis of cyanotic congenital heart disease (CCHD) is pathologically different from primary erythrocytosis of polycythemia vera (PV). An association between elevated hematocrit and thrombosis has been established in PV patients, and treatment guidelines recommend maintaining hematocrit <45%. Although an association between elevated hematocrit and thrombosis has not been established in CCHD and secondary erythrocytosis, the current clinical practice is to phlebotomize these patients to hematocrit <65%. We report a 21-year-old woman with CCHD who presented with symptomatic erythrocytosis with numbness and tingling with hemoglobin 25.2 g/dl and hematocrit 75.8%. Her symptoms resolved with IV hydration. Other factors, including dehydration and iron deficiency, may precipitate hyperviscosity symptoms. The treatment is volume replacement and low-dose iron therapy, not phlebotomy. Repeated phlebotomy causes iron deficiency with microcytic erythrocytes, which increases the whole blood viscosity and, therefore, can potentially accentuate rather than decrease the risk for a cerebrovascular accident.
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PMID:Cyanotic congenital heart disease (CCHD) with symptomatic erythrocytosis. 1791 83


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