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Haematologica 2000
Topics: Adrenal Hyperplasia, Congenital; Adult; Humans; Male; Polycythemia
PubMed: 11114823
DOI: No ID Found -
Hospital Practice (1995) Mar 1996Most causes of an elevated hematocrit can be determined with a simple workup that includes a complete blood count and chest x-ray. However, measurement of red blood cell...
Most causes of an elevated hematocrit can be determined with a simple workup that includes a complete blood count and chest x-ray. However, measurement of red blood cell mass and plasma volume is required to differentiate primary, secondary, and combined polycythemia. Phlebotomy is customary for primary disease and some secondary cases in which the underlying cause cannot be removed.
Topics: Aged; Algorithms; Aspirin; Combined Modality Therapy; Decision Trees; Diagnosis, Differential; Erythrocyte Indices; Hematocrit; Humans; Male; Phlebotomy; Platelet Aggregation Inhibitors; Platelet Count; Polycythemia
PubMed: 8596001
DOI: No ID Found -
British Journal of Haematology Sep 1969
Topics: Blood Volume; Chronic Disease; Erythrocytes; Heart Failure; Humans; Hypoxia; Lung Diseases; Plasma Volume; Polycythemia
PubMed: 5806445
DOI: No ID Found -
Haematologica Jan 2005Congenital polycythemias may result from inherited defects in hypoxia sensing, from inherited intrinsic defects in red blood cell precursors, or from inherited... (Review)
Review
Congenital polycythemias may result from inherited defects in hypoxia sensing, from inherited intrinsic defects in red blood cell precursors, or from inherited conditions that cause low tissue oxygen tension and secondary polycythemia. Conditions of defective hypoxia sensing feature inappropriately normal or elevated serum erythropoietin (Epo) concentrations in the setting of normoxia and erythrocytosis. They are often due to homozygous or compound heterozygous germline mutations in the von Hippel Lindau tumor suppressor gene (VHL) but without increased incidence of tumors. Affected persons have a high risk of arterial thrombosis and early mortality. The molecular biology of rare polycythemic patients with a single mutated VHL allele remains obscure. Primary congenital and familial polycythemias are characterized by low Epo levels and increased erythroid precursor responsiveness to Epo. They are often due to heterozygous gain-of function mutations in the gene for erythropoietin receptor (EPOR). Secondary congenital polycythemias have low tissue oxygen tension due to hemoglobins with high affinity for oxygen, low erythrocyte 2,3 biphosphoglycerate levels, methemoglobinemia or cyanotic heart or lung disease. Whether phlebotomy therapy reduces complications and prolongs survival in congenital polycythemia is not known.
Topics: Homeostasis; Homozygote; Humans; Oxygen; Point Mutation; Polycythemia; Russia; Von Hippel-Lindau Tumor Suppressor Protein
PubMed: 15642677
DOI: No ID Found -
Current Opinion in Hematology Mar 1995In this review, primary polycythemic states are discussed in the context of other polycythemic disorders. Primary polycythemias result from an acquired or inborn... (Review)
Review
In this review, primary polycythemic states are discussed in the context of other polycythemic disorders. Primary polycythemias result from an acquired or inborn mutation affecting hematopoietic and erythroid cells. The best-known type of primary polycythemia is polycythemia vera, which is caused by an acquired somatic mutation of a hematopoietic stem cell with exaggerated myeloid proliferation; the molecular events leading to this disease are not understood. In contrast, primary familial and congenital polycythemias result from inborn mutation affecting hematopoietic and erythroid cells. The molecular mechanisms causing primary familial and congenital polycythemias may be different in different families; some have already been defined. Progress in defining the molecular defect of primary polycythemias and the better understanding of altered signal transduction leading to excessive erythrocyte production should provide important insights into the pathogenesis of primary polycythemias, other leukemic disorders, as well as normal hematopoiesis. Such information should contribute to better understanding of and more effective therapeutic interventions in myeloproliferative and leukemic disorders.
Topics: Erythropoiesis; Genome, Human; Germ-Line Mutation; Humans; Mutation; Oxygen; Polycythemia; Russia; Signal Transduction
PubMed: 9371985
DOI: 10.1097/00062752-199502020-00007 -
International Journal of Laboratory... May 2018Congenital Erythrocytosis (CE) represents a rare and heterogeneous clinical entity. It is caused by deregulated erythropoiesis where red blood cell overproduction... (Review)
Review
INTRODUCTION
Congenital Erythrocytosis (CE) represents a rare and heterogeneous clinical entity. It is caused by deregulated erythropoiesis where red blood cell overproduction results in elevated hemoglobin and hematocrit levels. CE may either be primary or secondary to elevated erythropoietin concentrations. The only known form of primary CE is caused by mutations in the EPOR gene. Secondary CE can be a consequence of tissue hypoxia, being caused by congenital defects such as hemoglobin variants with increased oxygen affinity, due to mutations in the α- or β-globin genes (HBB, HBA2, HBA1), or due to mutations in the BPGM gene. Secondary CE can also result from defects in the components of the oxygen-sensing pathway (PHD2, HIF2α and VHL).
METHODOLOGY
The family history and the quantification of serum EPO are mandatory to define the best diagnostic strategy regarding molecular studies. Based upon the serum EPO level, P50 and familial data, it is possible to establish a diagnostic algorithm.
RESULTS
Despite recent important discoveries in the molecular pathogenesis of CE, in about 70% of the patients the genetic causes remain to be identified. Clinical data on patients suffering from CE are sparse. This fact is conditional upon the effective way to predict the disease evolution, the establishment of the best management and the genetic counselling.
CONCLUSION
The number and phenotypic variability of patients that remain without an identified etiology suggest that other genes have to be implicated. Studies by next generation sequencing methodologies are already being performed and it is expected the identification of other genes involved in the pathophysiology of the CE.
Topics: Erythropoietin; Humans; Hypoxia; Mutation; Polycythemia
PubMed: 29741264
DOI: 10.1111/ijlh.12828 -
British Journal of Haematology Sep 1969
Topics: Humans; Leukemia; Liver; Polycythemia; Polycythemia Vera; Primary Myelofibrosis; Spleen
PubMed: 5806443
DOI: No ID Found -
Journal of Clinical Pathology Jan 1998
Topics: Abdomen; Humans; Polycythemia; Polycythemia Vera; Ultrasonography
PubMed: 9577361
DOI: 10.1136/jcp.51.1.1 -
Canadian Medical Association Journal Feb 1969
Topics: Adenocarcinoma; Adult; Alkalosis; Cystadenocarcinoma; Emphysema; Female; Hemangiosarcoma; Humans; Hypoxia; Kidney Neoplasms; Male; Obesity Hypoventilation Syndrome; Ovarian Neoplasms; Polycythemia; Polycythemia Vera
PubMed: 5812662
DOI: No ID Found -
Kidney International Apr 2003Posttransplant erythrocytosis (PTE) is defined as a persistently elevated hematocrit to a level greater than 51% after renal transplantation. It occurs in 10% to 15% of... (Review)
Review
Posttransplant erythrocytosis (PTE) is defined as a persistently elevated hematocrit to a level greater than 51% after renal transplantation. It occurs in 10% to 15% of graft recipients and usually develops 8 to 24 months after engraftment. Spontaneous remission of established PTE is observed in one fourth of the patients within 2 years from onset, whereas in the remaining three fourths it persists for several years, only to remit after loss of renal function from rejection. Predisposing factors include male gender, retention of native kidneys, smoking, transplant renal artery stenosis, adequate erythropoiesis prior to transplantation, and rejection-free course with well-functioning renal graft. Just as in other forms of erythrocytosis, a substantial number (approximately 60%) of patients with PTE experience malaise, headache, plethora, lethargy, and dizziness. Thromboembolic events occur in 10% to 30% of the cases; 1% to 2% eventually die of associated complications. Posttransplant erythrocytosis results from the combined trophic effect of multiple and interrelated erythropoietic factors. Among them, endogenous erythropoietin appears to play the central role. Persistent erythropoietin secretion from the diseased and chronically ischemic native kidneys does not conform to the normal feedback regulation, thereby establishing a form of "tertiary hypererythropoietinemia." However, erythropoietin levels in most PTE patients still remain within the "normal range," indicating that erythrocytosis finally ensues by the contributory action of additional growth factors on erythroid progenitors, such as angiotensin II, androgens, and insulin-like growth factor 1 (IGF-1). Inactivation of the renin-angiotensin system (RAS) by an angiotensin-converting enzyme (ACE) inhibitor, or an angiotensin II type 1 AT1 receptor blocker represents the most effective, safe, and well-tolerated therapeutic modality.
Topics: Humans; Kidney Transplantation; Polycythemia; Postoperative Complications
PubMed: 12631334
DOI: 10.1046/j.1523-1755.2003.00850.x