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Noumani I, Harrison CN, McMullin MF. Erythrocytosis: Diagnosis and investigation. Int J Lab Hematol 2024; 46 Suppl 1:55-62. [PMID: 38695361 DOI: 10.1111/ijlh.14298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 03/30/2024] [Indexed: 05/21/2024]
Abstract
An absolute erythrocytosis is present when the red cell mass is greater than 125% of the predicted. This is suspected when the hemoglobin or hematocrit is above the normal range. An erythrocytosis can be classified as primary or secondary and congenital or acquired. The commonest primary acquired disorder is polycythemia vera. The diagnostic criteria for PV have evolved over time and this is the main diagnosis managed in hematology clinics. There are a variety of rare congenital causes both primary and secondary. In particular in young patients and/or those with a family history a congenital cause is suspected. There remains a larger cohort with acquired erythrocytosis mainly with non-hematological pathology. In order to explore for a cause of erythrocytosis, measurement of the erythropoietin level is a first step. A low erythropoietin level indicates a primary cause and a normal or elevated level indicates a secondary etiology. Further investigation is then dictated by initial findings and includes mutational testing with PCR and NGS for those in whom a congenital cause is suspected. Following this possibly bone marrow biopsy, scans, and further investigation as indicated by history and initial findings. Investigation is directed toward the identification of those with a hematological disorder which would be best managed following guidelines in hematology clinics and referral elsewhere in those for whom there are non-hematological reasons for the elevated hemoglobin.
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Affiliation(s)
- Iman Noumani
- Department of Haematology, Guy's and St Thomas', London, UK
- Department of Haematology, Oman Medical Specialty Board, Muscat, Oman
| | - Claire N Harrison
- Department of Haematology, Oman Medical Specialty Board, Muscat, Oman
- Department of Haematology, Queen's University, Belfast, Northern Ireland
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2
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O'Neill C, O'Connell C. Idiopathic erythrocytosis: A diagnostic and management challenge with emerging areas for exploration. Br J Haematol 2024; 204:774-783. [PMID: 38262687 DOI: 10.1111/bjh.19287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 12/18/2023] [Accepted: 12/22/2023] [Indexed: 01/25/2024]
Abstract
Despite published algorithms for approaching the work-up of erythrocytosis, a significant proportion of patients are left with uncertainty as to its aetiology and prognosis. The term 'idiopathic erythrocytosis' (IE) is applied when known primary and secondary aetiologies have been ruled out. However, the assignment of secondary aetiologies is not always straightforward or evidence based, which can lead to misdiagnosis and heterogeneity in cohort studies. Furthermore, new studies have identified germline or somatic mutations that may affect prognosis. Epidemiological and cohort data are inconsistent as to whether IE increases the risk for complications such as arterial and venous thromboembolism, clonal transformation or comorbid conditions. Randomized trials assessing the role of phlebotomy for long-term management of IE have not been performed, so treatment remains a vexing problem for clinicians. Standardization of terminology and testing strategies, including comprehensive genetic screening in clinical research, are key to refining our understanding of IE.
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Affiliation(s)
- Caitlin O'Neill
- Jane Anne Nohl Division of Hematology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Casey O'Connell
- Jane Anne Nohl Division of Hematology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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3
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Komninaka V, Flevari P, Ntelaki EE, Yfanti E, Androutsakos T, Ntanasis-Stathopoulos I, Terpos E. High-Oxygen-Affinity Hemoglobins-Case Series and Review of the Literature. J Clin Med 2024; 13:458. [PMID: 38256595 PMCID: PMC10815990 DOI: 10.3390/jcm13020458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 01/09/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Modifications of the hemoglobin (Hb) structure in regions involving the regulation of oxygen transport may lead to an increased oxygen affinity for the hemoglobin molecule and impaired oxygen delivery to the tissues. Herein, we present six patients with high-oxygen-affinity Hb variants, either in heterozygous form or in compound heterozygosity (such as heterozygosity for Hb Hiroshima, Köln, Crete, and compound heterozygosity Hb Crete with β or δβ thalassemia), in order to demonstrate the need for prompt and accurate diagnosis and enrich the limited literature due to the rarity of such cases. Hb Crete, Hb Hiroshima, and Hb Köln have distinct pathophysiologies and may result in different clinical phenotypes. In conclusion, high-oxygen-affinity hemoglobins are rare and inherited within a dominant autosomal manner, have various clinical presentations, and should always be suspected in patients with erythrocytosis. Their management (as phlebotomy or low-dose aspirin) should be based on an individualized assessment of the risk of complications, the medical history, concomitant symptoms, and quality of life.
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Affiliation(s)
- Veroniki Komninaka
- Centre of Excellence in Rare Haematological (Haemoglobinopathies) & Rare Metabolic (Gaucher Disease) Diseases, Laiko General Hospital, 11527 Athens, Greece; (V.K.); (P.F.); (E.-E.N.); (E.Y.)
| | - Pagona Flevari
- Centre of Excellence in Rare Haematological (Haemoglobinopathies) & Rare Metabolic (Gaucher Disease) Diseases, Laiko General Hospital, 11527 Athens, Greece; (V.K.); (P.F.); (E.-E.N.); (E.Y.)
| | - Evangelia-Eleni Ntelaki
- Centre of Excellence in Rare Haematological (Haemoglobinopathies) & Rare Metabolic (Gaucher Disease) Diseases, Laiko General Hospital, 11527 Athens, Greece; (V.K.); (P.F.); (E.-E.N.); (E.Y.)
| | - Eleni Yfanti
- Centre of Excellence in Rare Haematological (Haemoglobinopathies) & Rare Metabolic (Gaucher Disease) Diseases, Laiko General Hospital, 11527 Athens, Greece; (V.K.); (P.F.); (E.-E.N.); (E.Y.)
| | - Theodoros Androutsakos
- Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | - Ioannis Ntanasis-Stathopoulos
- Department of Clinical Therapeutics, School of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece
| | - Evangelos Terpos
- Department of Clinical Therapeutics, School of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece
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4
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Filser M, Gardie B, Wemeau M, Aguilar-Martinez P, Giansily-Blaizot M, Girodon F. Importance of Sequencing HBA1, HBA2 and HBB Genes to Confirm the Diagnosis of High Oxygen Affinity Hemoglobin. Genes (Basel) 2022; 13:132. [PMID: 35052472 PMCID: PMC8774638 DOI: 10.3390/genes13010132] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/05/2022] [Accepted: 01/10/2022] [Indexed: 12/03/2022] Open
Abstract
High oxygen affinity hemoglobin (HOAH) is the main cause of constitutional erythrocytosis. Mutations in the genes coding the alpha and beta globin chains (HBA1, HBA2 and HBB) strengthen the binding of oxygen to hemoglobin (Hb), bringing about tissue hypoxia and a secondary erythrocytosis. The diagnosis of HOAH is based upon the identification of a mutation in HBA1, HBA2 or HBB in specialized laboratories. Phenotypic studies of Hb are also useful, but electrophoretic analysis can be normal in 1/3 of cases. The establishment of the dissociation curve of Hb can be used as another screening test, a shift to the left indicating an increased affinity for Hb. The direct measurement of venous P50 using a Hemox Analyzer is of great importance, but due to specific analytic conditions, it is only available in a few specialized laboratories. Alternatively, an estimated measurement of the P50 can be obtained in most of the blood gas analyzers on venous blood. The aim of our study was therefore to determine whether a normal venous P50 value could rule out HOAH. We sequenced the HBB, HBA1 and HBA2 genes of 75 patients with idiopathic erythrocytosis. Patients had previously undergone an exhaustive medical check-up after which the venous P50 value was defined as normal. Surprisingly, sequencing detected HOAH in three patients (Hb Olympia in two patients, and Hb St Nazaire in another). A careful retrospective examination of their medical files revealed that (i) one of the P50 samples was arterial; (ii) there was some air in another sample; and (iii) the P50 measurement was not actually done in one of the patients. Our study shows that in real life conditions, due to pre-analytical contingencies, a venous P50 value that is classified as being normal may not be sufficient to rule out a diagnosis of HOAH. Therefore, we recommend the systematic sequencing of the HBB, HBA1 and HBA2 genes in the exploration of idiopathic erythrocytosis.
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Affiliation(s)
- Mathilde Filser
- Biology Division, Department of Biological Hematology, Dijon Hospital, 21000 Dijon, France;
| | - Betty Gardie
- Thorax Institute, Nantes Hospital, CNRS, Inserm, Nantes University, 44000 Nantes, France;
- Ecole Pratique des Hautes Etudes, EPHE, Science and Letters Paris University, 75014 Paris, France
- Laboratory of Excellence GR-Ex, 75015 Paris, France
| | - Mathieu Wemeau
- Blood Disease Department, Claude Huriez Hospital, Lille Hospital, 59000 Lille, France;
| | - Patricia Aguilar-Martinez
- Department of Biological Hematology, Saint Eloi Hospital, Montpellier Hospital & Montpellier University, 34000 Montpellier, France; (P.A.-M.); (M.G.-B.)
| | - Muriel Giansily-Blaizot
- Department of Biological Hematology, Saint Eloi Hospital, Montpellier Hospital & Montpellier University, 34000 Montpellier, France; (P.A.-M.); (M.G.-B.)
| | - François Girodon
- Biology Division, Department of Biological Hematology, Dijon Hospital, 21000 Dijon, France;
- Laboratory of Excellence GR-Ex, 75015 Paris, France
- Inserm U1231, Bourgogne University, 21000 Dijon, France
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5
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Anžej Doma S, Drnovšek E, Kristan A, Fink M, Sever M, Podgornik H, Belčič Mikič T, Debeljak N, Preložnik Zupan I. Diagnosis and management of non-clonal erythrocytosis remains challenging: a single centre clinical experience. Ann Hematol 2021; 100:1965-1973. [PMID: 34013406 PMCID: PMC8285333 DOI: 10.1007/s00277-021-04546-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/01/2021] [Indexed: 12/31/2022]
Abstract
Erythrocytosis has a diverse background. While polycythaemia vera has well defined criteria, the diagnostic approach and management of other types of erythrocytosis are more challenging. The aim of study was to retrospectively analyse the aetiology and management of non-clonal erythrocytosis patients referred to a haematology outpatient clinic in an 8-year period using a 3-step algorithm. The first step was inclusion of patients with Hb > 185 g/L and/or Hct > 0.52 in men and Hb > 165 g/L and/or Hct > 0.48 in women on two visits ≥ two months apart, thus confirming true erythrocytosis. Secondly, polycythaemia vera was excluded and secondary causes of erythrocytosis (SE) identified. Thirdly, idiopathic erythrocytosis patients (IE) were referred to next-generation sequencing for possible genetic background evaluation. Of the 116 patients, 75 (65%) are men and 41 (35%) women, with non-clonal erythrocytosis 34/116 (29%) had SE, 15/116 (13%) IE and 67/116 (58%) stayed incompletely characterized (ICE). Patients with SE were significantly older and had significantly higher Hb and Hct compared to patients with IE. Most frequently, SE was attributed to obstructive sleep apnoea and smoking. Phlebotomies were performed in 56, 53 and 40% of patients in the SE, IE, and ICE group, respectively. Approx. 70% of patients in each group received aspirin. Thrombotic events were registered in 12, 20 and 15% of SE, IE and ICE patients, respectively. Congenital erythrocytosis type 4 (ECYT4) was diagnosed in one patient. The study demonstrates real-life management of non-clonal erythrocytosis which could be optimized using a 3-step diagnostic algorithm.
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Affiliation(s)
- Saša Anžej Doma
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Korytkova 2, 1000, Ljubljana, Slovenia
| | - Eva Drnovšek
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.,Medical Centre for Molecular Biology, Institute of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia
| | - Aleša Kristan
- Medical Centre for Molecular Biology, Institute of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia
| | - Martina Fink
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia
| | - Matjaž Sever
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Korytkova 2, 1000, Ljubljana, Slovenia
| | - Helena Podgornik
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.,Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000, Ljubljana, Slovenia
| | - Tanja Belčič Mikič
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Korytkova 2, 1000, Ljubljana, Slovenia
| | - Nataša Debeljak
- Medical Centre for Molecular Biology, Institute of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia
| | - Irena Preložnik Zupan
- Department of Haematology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia. .,Faculty of Medicine, University of Ljubljana, Korytkova 2, 1000, Ljubljana, Slovenia.
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6
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Shi F, Sun LX, Long S, Zhang Y. Pheochromocytoma as a cause of repeated acute myocardial infarctions, heart failure, and transient erythrocytosis: A case report and review of the literature. World J Clin Cases 2021; 9:951-959. [PMID: 33585644 PMCID: PMC7852630 DOI: 10.12998/wjcc.v9.i4.951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/25/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Pheochromocytoma is a rare catecholamines-secreting tumor arising from chromaffin cells in the adrenal medulla. It classically presents with paroxysmal hypertension, headaches, palpitations, sweating, and metabolic disorders. Atypical presentations such as acute myocardial infarction, heart failure, cardiomyopathy, stroke, and transient erythrocytosis have been infrequently documented.
CASE SUMMARY We describe the case of a 72-year-old man diagnosed with pheochromocytoma presenting with non-ST segment elevation myocardial infarction, heart failure, and transient erythrocytosis with nonobstructed coronary arteries. This was his second heart attack. The patient was previously diagnosed with myocardial infarction, and an immense mass was found on the left adrenal gland 3 years prior. Based on clinical and laboratory findings, a diagnosis of pheochromocytoma was confirmed. His coronary angiogram showed nonobstructed coronary arteries except for a myocardial bridge in the left anterior descending branch. This was a form of type-2 myocardial infarction. The myocardial cell lesions were caused by sudden secretion of catecholamines by the pheochromocytoma. Even more atypically, his hemoglobin level was obviously elevated at admission, but after a few days of treatment with an alpha-adrenergic receptor blocker, it dropped to normal levels without additional treatment.
CONCLUSION Pheochromocytoma may be a cause of acute myocardial infarction, heart failure, and transient erythrocytosis.
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Affiliation(s)
- Fei Shi
- Department of Cardiology, Affiliated Hospital of Chengde Medical University, Chengde 067000, Hebei Province, China
| | - Li-Xian Sun
- Department of Cardiology, Affiliated Hospital of Chengde Medical University, Chengde 067000, Hebei Province, China
| | - Sen Long
- Department of Traditional Chinese Medicine, Affiliated Hospital of Chengde Medical University, Chengde 067000, Hebei Province, China
| | - Ying Zhang
- Department of Cardiology, Affiliated Hospital of Chengde Medical University, Chengde 067000, Hebei Province, China
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7
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Filser M, Aral B, Airaud F, Chauveau A, Bruce A, Polfrit Y, Thiebaut A, Gauthier M, Le Maréchal C, Lippert E, Béziau S, Garrec C, Gardie B, Girodon F. Low incidence of EPOR mutations in idiopathic erythrocytosis. Haematologica 2021; 106:299-301. [PMID: 32165487 PMCID: PMC7776331 DOI: 10.3324/haematol.2019.244160] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - Bernard Aral
- Laboratoire de genetique chromosomique et moleculaire, Pôle Biologie, CHU de Dijon
| | | | | | - Aisha Bruce
- Dept of Pediatrics, University of Alberta and Stollery Children's Hospital, Edmonton
| | | | | | - Martin Gauthier
- Service d'Hematologie, Toulouse-Oncopole University Cancer Institute (IUCT-O), Toulouse
| | | | - Eric Lippert
- Hematologie Biologique, CHU Brest, Université de Brest, Brest
| | - Stéphane Béziau
- Service de Genetique Medicale, CHU Nantes, Institut du Thorax, Nantes
| | - Céline Garrec
- Service de Genetique Medicale, CHU de Nantes, Nantes
| | - Betty Gardie
- Institut du Thorax, EPHE, PSL research University, Laboratory of Excellence GR-Ex, Nantes
| | - François Girodon
- Pole Biologie, Laboratory of Excellence GR-Ex, Université de Bourgogne, Dijon
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8
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Gangat N, Szuber N, Pardanani A, Tefferi A. JAK2 unmutated erythrocytosis: current diagnostic approach and therapeutic views. Leukemia 2021; 35:2166-2181. [PMID: 34021251 PMCID: PMC8324477 DOI: 10.1038/s41375-021-01290-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/28/2021] [Accepted: 05/06/2021] [Indexed: 02/08/2023]
Abstract
JAK2 unmutated or non-polycythemia vera (PV) erythrocytosis encompasses both hereditary and acquired conditions. A systematic diagnostic approach begins with documentation of historical hematocrit (Hct)/hemoglobin (Hgb) measurements and classification of the process as life-long/unknown duration or acquired. Further investigation in both categories is facilitated by determination of serum erythropoietin level (EPO). Workup for hereditary/congenital erythrocytosis requires documentation of family history and laboratory screening for high-oxygen affinity hemoglobin variants, 2, 3 biphosphoglycerate deficiency, and germline mutations that are known to alter cellular oxygen sensing (e.g., PHD2, HIF2A, VHL) or EPO signaling (e.g., EPOR mutations); the latter is uniquely associated with subnormal EPO. Acquired erythrocytosis is often elicited by central or peripheral hypoxia resulting from cardiopulmonary disease/high-altitude dwelling or renal artery stenosis, respectively; EPO in the former instance is often normal (compensated by negative feed-back). Other conditions associated with acquired erythrocytosis include EPO-producing tumors and the use of drugs that promote erythropoiesis (e.g., testosterone, erythropoiesis stimulating agents). "Idiopathic erythrocytosis" loosely refers to an otherwise not explained situation. Historically, management of non-PV erythrocytosis has been conflicted by unfounded concerns regarding thrombosis risk, stemming from limited phenotypic characterization, save for Chuvash polycythemia, well-known for its thrombotic tendency. In general, cytoreductive therapy should be avoided and phlebotomy is seldom warranted where frequency is determined by symptom control rather than Hct threshold. Although not supported by hard evidence, cardiovascular risk optimization and low-dose aspirin use are often advised. Application of modern genetic tests and development of controlled therapeutic intervention trials are needed to advance current clinical practice.
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Affiliation(s)
- Naseema Gangat
- grid.66875.3a0000 0004 0459 167XDivision of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN USA
| | - Natasha Szuber
- grid.14848.310000 0001 2292 3357Department of Hematology, Université de Montréal, Montréal, QC Canada
| | - Animesh Pardanani
- grid.66875.3a0000 0004 0459 167XDivision of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN USA
| | - Ayalew Tefferi
- grid.66875.3a0000 0004 0459 167XDivision of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN USA
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9
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Chepurnaya AN, Safuanova GS, Nikulicheva VI, Lekhmus TY, Rakhmatullina AR. [Erythrocytoses in patients with dilated and ischemic cardiomyopathy.]. Klin Lab Diagn 2020; 65:222-227. [PMID: 32227727 DOI: 10.18821/0869-2084-2020-65-4-222-227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 01/15/2020] [Indexed: 01/29/2023]
Abstract
The aim of research was to evaluate the impact of erythrocytoses on processes of cardiovascular system's remodelling in patients with dilated and ishaemic cardiomyopathies. 35 (42,2%) patients with dilated cardiomyopathy (DCMP) with erythrocytoses, 19 (23,5%) without erythrocytosis, 34 (28,4%) patients with ishaemic cardiomyopathy (ICMP) with erythrocytosis and 50 (60,1%) without erythrocytosis were included in the study. It has been established that erythrocytoses don't wield major influence on the heart's haemodynamics, they appear as a consequence of main diseases and not as their reason, which confirms the domination of congestive heart failure's signs of III-IV stages. In patients with DCMP and ICMP signs of tissue hypoxia were established as well as oxygen reduction in arterial blood to 60,70 ± 1,24 mm Hg in cases of DCMP and 59,60 ± 1,24 mm Hg in cases of ICMP (in verification 75,44 ± 0,93) - p < 0,001. Arguably, erythrocytoses in cases of DCMP and ICMP are a consequence of congestive heart failure, leading to hypoxic erythrocytosis.
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Affiliation(s)
- A N Chepurnaya
- Federal State Budgetary and Educational Institution of Higher Education of the Russian Federation "Bashkir State Medical University", 450000, Ufa, Russian Federation
| | - G S Safuanova
- Federal State Budgetary and Educational Institution of Higher Education of the Russian Federation "Bashkir State Medical University", 450000, Ufa, Russian Federation
| | - V I Nikulicheva
- Federal State Budgetary and Educational Institution of Higher Education of the Russian Federation "Bashkir State Medical University", 450000, Ufa, Russian Federation
| | - T Y Lekhmus
- Federal State Budgetary and Educational Institution of Higher Education of the Russian Federation "Bashkir State Medical University", 450000, Ufa, Russian Federation
| | - A R Rakhmatullina
- Publicly Funded Health Facility n.a. G.G. Kuvatov, 450005, Ufa, Russian Federation
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10
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Khurana H, Lakshman P, Kumar K, Jain A. Dissecting Primary Erythrocytosis Among Polycythemia Patients Referred to an Indian Armed Forces Hospital. Indian J Hematol Blood Transfus 2020; 36:187-191. [PMID: 32158103 DOI: 10.1007/s12288-019-01155-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 06/24/2019] [Indexed: 11/29/2022] Open
Abstract
Referrals for evaluation of polycythemia cases have increased since the hemoglobin (Hb) thresholds for diagnosis of Polycythemia Vera (PV) have been lowered by WHO. The current study enrolled patients of age > 18 years from the Indian Armed Forces or their family members with polycythemia from November 2016 to October 2018. After exclusion of secondary causes, 49 patients were diagnosed as Primary Erythrocytosis (PE). The patients were classified into two groups: PV and Idiopathic Erythrocytosis (IE) and a systematic comparison of clinical and laboratory features of the two groups was done. The prevalence of PV in PE was 20.4% (10 of 49) while the rest 39 (79.6%) had IE. Seven PV patients had JAK2 V617F mutation, one had JAK2 Exon12 mutation, and two were JAK2 negative PV. Nine of 10 (90%) PV patients had Hb > 18.5 g/dl, while only 21 of 39 (53.8%) IE patients had Hb > 18.5 g/dl (p = 0.06). None of the JAK2 mutated patients had Hb < 18.5 g/dl. We conclude that PV is more prevalent in patients of PE with Hb > 18.5 g/dl. Most patients with Hb between 16.5-18.5 g/dl would still be classified as IE. We advocate the need for further studies evaluating the utility of investigating all patients of PE with the revised WHO Hb threshold as well as studies on genetic profile of IE patients from India.
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Affiliation(s)
- Harshit Khurana
- 1Medical Division, Command Hospital Air Force (CHAF), Bangalore, Karnataka India
| | - Praveen Lakshman
- 1Medical Division, Command Hospital Air Force (CHAF), Bangalore, Karnataka India
| | - Kishore Kumar
- 1Medical Division, Command Hospital Air Force (CHAF), Bangalore, Karnataka India
| | - Arihant Jain
- 2Department of Internal Medicine (Clinical Hematology Division), Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
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11
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Sacco M, Ranalli P, Lancellotti S, Petrucci G, Dragani A, Rocca B, De Cristofaro R. Increased von Willebrand factor levels in polycythemia vera and phenotypic differences with essential thrombocythemia. Res Pract Thromb Haemost 2020; 4:413-421. [PMID: 32211575 PMCID: PMC7086469 DOI: 10.1002/rth2.12315] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/13/2020] [Accepted: 01/17/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Acquired von Willebrand factor (VWF) deficiency was described in Philadelphia-negative myeloproliferative neoplasms, especially in essential thrombocythemia (ET). VWF phenotype in contemporary patients with polycythemia vera (PV) remains less explored. OBJECTIVES To characterize the VWF phenotype in PV and to compare VWF phenotype in PV with matched healthy subjects and ET patients. PATIENTS/METHODS We studied 48 PV patients, treated according to current recommendations (hematocrit ≤ 45%, on low-dose aspirin prophylaxis); 48 healthy and 41 subjects with ET, all sex, age, and blood group matched. We measured VWF antigen, activity, multimeric pattern, ADAMTS-13, and factor VIII (FVIII) antigen. RESULTS In patients with PV, VWF antigen and activity were significantly higher than in healthy subjects (antigen: 119[96-137] vs 93[79-107] IU/dL; activity: 114[95-128] vs 90[79-107] IU/dL, respectively, medians and interquartile, P < 0.01), with normal multimeric distribution. ADAMTS-13 levels were similar between patients with PV and healthy subjects. FVIII levels were higher in PV than in healthy subjects (141[119-169] versus 98[88-123] IU/dL, respectively, P < 0.01). By multivariable analysis, JAK2-p.V617F allelic burden, erythrocyte count, and male sex significantly predicted VWF antigen and activity levels. As compared to patients with ET, patients with PV showed similar VWF antigen levels but approximately 40% higher activity (79[49-104] vs 112[93-125] IU/dL, respectively, P < 0.01). CONCLUSIONS Patients with PV show increased VWF and FVIII levels, predicted by JAK2-p.V617F burden and erythrocyte count. At variance with ET, acquired VWF defect was not observed in PV. High VWF/FVIII levels may sustain the thrombotic diathesis of PV and may be investigated as biomarkers for risk stratification.
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Affiliation(s)
- Monica Sacco
- Servizio Malattie Emorragiche e TromboticheFondazione Policlinico Universitario “A. Gemelli” IRCCSRomaItaly
| | - Paola Ranalli
- Dipartimento di Medicina Interna e Chirurgia TraslazionaleFacoltà di Medicina e Chirurgia “A. Gemelli”Università Cattolica del Sacro CuoreRomaItaly
| | | | - Giovanna Petrucci
- Istituto di FarmacologiaFacoltà di Medicina e Chirurgia “A. Gemelli”Università Cattolica del S. Cuore and Fondazione Policlinico Universitario “A. Gemelli” IRCCSRomeItaly
| | - Alfredo Dragani
- Dipartimento di Medicina Interna e Chirurgia TraslazionaleFacoltà di Medicina e Chirurgia “A. Gemelli”Università Cattolica del Sacro CuoreRomaItaly
| | - Bianca Rocca
- Istituto di FarmacologiaFacoltà di Medicina e Chirurgia “A. Gemelli”Università Cattolica del S. Cuore and Fondazione Policlinico Universitario “A. Gemelli” IRCCSRomeItaly
| | - Raimondo De Cristofaro
- Servizio Malattie Emorragiche e TromboticheFondazione Policlinico Universitario “A. Gemelli” IRCCSRomaItaly
- Dipartimento di EmatologiaOspedale S. SpiritoPescaraItaly
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12
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Bonnin A, Gardie B, Girodon F, Airaud F, Garrec C, Bézieau S, Vignon G, Mottaz P, Labrousse J, Lellouche F. [A new case of rare erythrocytosis due to EGLN1 mutation with review of the literature]. Rev Med Interne 2020; 41:196-199. [PMID: 31980185 DOI: 10.1016/j.revmed.2019.12.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/03/2019] [Accepted: 12/23/2019] [Indexed: 12/30/2022]
Abstract
INTRODUCTION The origin of polycythemia is often simple to detect. Sometimes it is necessary to look for hereditary forms, the decisive parameters being the dosage of erythropoietin and the measurement of the oxygen dissociation curve (P50). These rare diseases are related to high oxygen-affinity haemoglobins, abnormalities of the erythropoietin receptor or dysfunction of the HIF (hypoxia-inducible factor) pathway. CASE REPORT We report the case of a 56-year-old patient with unexplained polycythemia associated with normal serum erythropoietin and normal P50, in whom the never previously described mutation c.400C>T(p.Gln134*) on exon 1 in the EGLN1 gene (encoding PHD2) was found. CONCLUSION In the face of an unexplained polycythemia a good cooperation between clinicians and biologists is necessary to be able to characterize rare hereditary pathologies.
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Affiliation(s)
- A Bonnin
- Service de médecine interne, centre hospitalier de Royan, 20, avenue de Saint-Sordelin, 17640 Vaux sur mer, France
| | - B Gardie
- École pratique des hautes études (EPHE), PSL research university, les Patios Saint-Jacques, 4-14, rue Ferrus, 75014 Paris, France; Inserm, centre national de la recherche scientifique (CNRS), institut du thorax, université de Nantes, 8, quai Moncousu, 44007 Nantes, France; Laboratory of excellence GR-Ex, Paris, France
| | - F Girodon
- Laboratory of excellence GR-Ex, Paris, France; Service d'hématologie biologique, pôle biologie, CHU de Dijon, hôpital du Bocage, 14, rue Paul-Gaffarel, 21000 Dijon, France; Inserm U1231, université de Bourgogne, 21000 Dijon, France
| | - F Airaud
- Service de génétique médicale, CHU de Nantes, 8, quai Moncousu, 44007 Nantes, France
| | - C Garrec
- Service de génétique médicale, CHU de Nantes, 8, quai Moncousu, 44007 Nantes, France
| | - S Bézieau
- Inserm, centre national de la recherche scientifique (CNRS), institut du thorax, université de Nantes, 8, quai Moncousu, 44007 Nantes, France; Service de génétique médicale, CHU de Nantes, 8, quai Moncousu, 44007 Nantes, France
| | - G Vignon
- Laboratoire inter-hospitalier de biologie médicale, groupement de coopération sanitaire de Saintonge, centres hospitaliers de Saint-Jean-d'Angély, Saintes, Royan et Jonzac, 18, avenue du Port, 17400 Saint-Jean-d'Angély, France
| | - P Mottaz
- Service de médecine interne, centre hospitalier de Royan, 20, avenue de Saint-Sordelin, 17640 Vaux sur mer, France
| | - J Labrousse
- Laboratoire inter-hospitalier de biologie médicale, groupement de coopération sanitaire de Saintonge, centres hospitaliers de Saint-Jean-d'Angély, Saintes, Royan et Jonzac, 18, avenue du Port, 17400 Saint-Jean-d'Angély, France
| | - F Lellouche
- Service de médecine interne, centre hospitalier de Royan, 20, avenue de Saint-Sordelin, 17640 Vaux sur mer, France; Laboratoire inter-hospitalier de biologie médicale, groupement de coopération sanitaire de Saintonge, centres hospitaliers de Saint-Jean-d'Angély, Saintes, Royan et Jonzac, 18, avenue du Port, 17400 Saint-Jean-d'Angély, France.
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13
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de Guzman GS, Manalo EM. Myomatous erythrocytosis syndrome: A case series. Case Rep Womens Health 2019; 24:e00139. [PMID: 31497510 PMCID: PMC6722385 DOI: 10.1016/j.crwh.2019.e00139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/18/2019] [Accepted: 08/19/2019] [Indexed: 11/28/2022] Open
Abstract
Uterine leiomyomas are tumor-associated causes of secondary erythrocytosis. Ectopic erythropoietin production by fibroid smooth muscles has been proposed and demonstrated in the literature. Here, we present three cases of large leiomyomas with an incidental finding of isolated erythrocytosis on preoperative workup. Two patients underwent total abdominal hysterectomy while one patient underwent a myomectomy. Both histologic examination confirming the diagnosis of leiomyoma and serial complete blood counts showing normalization of postoperative hemoglobin levels together with isolated erythrocytosis constitute the criteria to fulfill a diagnosis of myomatous erythrocytosis syndrome. All three criteria were observed in the three cases described. To date, fewer than 40 cases have been reported worldwide. These are the first reported cases of myomatous erythrocytosis syndrome in the Philippines.
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Affiliation(s)
- Glaiza S. de Guzman
- Department of Obstetrics and Gynecology, University of the Philippines – Philippine General Hospital, Philippines
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14
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Rumi E, McMullin MF, Harrison C, Ellis MH, Barzilai M, Sarid N, Mesa R, Paoli C, Angona A, Sant’Antonio E, Ferretti VV, Cavalloni C, Casetti IC, Trotti C, Barbui T. Facing erythrocytosis: Results of an international physician survey. Am J Hematol 2019; 94:E225-E227. [PMID: 31148218 PMCID: PMC8204407 DOI: 10.1002/ajh.25545] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 05/28/2019] [Indexed: 01/09/2023]
Affiliation(s)
- Elisa Rumi
- Division of Hematology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | | | - Claire Harrison
- Department of Hematology, Guy’s and St. Thomas’ NHS Foundation Trust, London, UK
| | - Martin H. Ellis
- Hematology Institute, Meir Medical Center, Kfar Saba, Israel
| | - Merav Barzilai
- Hematology Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Nadav Sarid
- Hematology Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Ruben Mesa
- UT Health San Antonio Cancer Center, San Antonio, Texas
| | - Chiara Paoli
- CRIMM, Center Research and Innovation of Myeloproliferative Neoplasms, University of Florence, Florence, Italy
| | - Anna Angona
- Hematology Department-IMIM, Hospital del Mar, Universitat Autónoma de Barcelona, Barcelona, Spain
| | | | | | - Chiara Cavalloni
- Division of Hematology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | | | - Chiara Trotti
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Tiziano Barbui
- Research Foundation Ospedale Papa Giovanni XXIII Bergamo, Bergamo, Italy
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15
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Yudin J, Verhovsek M. How we diagnose and manage altered oxygen affinity hemoglobin variants. Am J Hematol 2019; 94:597-603. [PMID: 30690774 DOI: 10.1002/ajh.25425] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 01/23/2019] [Indexed: 01/14/2023]
Abstract
Altered oxygen affinity variant hemoglobins (Hbs) are caused by mutations of the globin genes. Changes in Hb oxygen affinity shift the oxygen dissociation curve, and can be identified by abnormal p50 measurements of patient red blood cells. Variants are categorized as either low oxygen affinity (high p50) or high oxygen affinity (low p50). Accurate diagnosis requires recognition of typical clinical and laboratory findings. In this case-based review, we present two patients with altered oxygen affinity variants, illustrating barriers to prompt and accurate diagnosis, and issues in management. We then review pathophysiology, diagnostic tests, clinical features, and management strategies.
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Affiliation(s)
- Jovana Yudin
- Division of Hematology, Department of MedicineUniversity of Toronto Toronto Ontario Canada
| | - Madeleine Verhovsek
- Division of Hematology, Department of MedicineMcMaster University Hamilton Ontario Canada
- Department of Pathology and Molecular MedicineMcMaster University Hamilton Ontario Canada
- Molecular Hematology and GeneticsHamilton Regional Laboratory Medicine Program Hamilton Ontario Canada
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16
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Griesshammer M, Kiladjian JJ, Besses C. Thromboembolic events in polycythemia vera. Ann Hematol 2019; 98:1071-1082. [PMID: 30848334 PMCID: PMC6469649 DOI: 10.1007/s00277-019-03625-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 01/28/2019] [Indexed: 12/19/2022]
Abstract
Thromboembolic events and cardiovascular disease are the most prevalent complications in patients with polycythemia vera (PV) compared with other myeloproliferative disorders and are the major cause of morbidity and mortality in this population. Moreover, a vascular complication such as arterial or venous thrombosis often leads to the diagnosis of PV. The highest rates of thrombosis typically occur shortly before or at diagnosis and decrease over time, probably due to the effects of treatment. Important risk factors include age (≥ 60 years old) and a history of thrombosis; elevated hematocrit and leukocytosis are also associated with an increased risk of thrombosis. The goal of therapy is to reduce the risk of thrombosis by controlling hematocrit to < 45%, a target associated with reduced rates of cardiovascular death and major thrombosis. Low-risk patients (< 60 years old with no history of thrombosis) are managed with phlebotomy and low-dose aspirin, whereas high-risk patients (≥ 60 years old and/or with a history of thrombosis) should be treated with cytoreductive agents. Interferon and ruxolitinib are considered second-line therapies for patients who are intolerant of or have an inadequate response to hydroxyurea, which is typically used as first-line therapy. In this review, we discuss factors associated with thrombosis and recent data on current treatments, including anticoagulation, highlighting the need for more controlled studies to determine the most effective cytoreductive therapies for reducing the risk of thrombosis in patients with PV.
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Affiliation(s)
- Martin Griesshammer
- University Clinic for Hematology, Oncology, Hemostaseology and Palliative Care, Johannes Wesling Medical Center Minden, UKRUB, University of Bochum, Hans-Nolte-Straße 1, 32429, Minden, Germany.
| | - Jean-Jacques Kiladjian
- Hôpital Saint-Louis, AP-HP, Centre d'Investigations Cliniques (CIC 1427), Université Paris Diderot, INSERM UMRS 1131, 1 Avenue Claude Vellefaux, Paris, France
| | - Carlos Besses
- Hospital del Mar-IMIM, Passeig Marítim 25-29, 08003, Barcelona, Spain
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17
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Barradas J, Rodrigues CD, Ferreira G, Rocha P, Constanço C, Andrade MR, Bento C, Silva HM. Congenital erythrocytosis - discover of a new mutation in the EGLN1 gene. Clin Case Rep 2018; 6:1109-1111. [PMID: 29881576 PMCID: PMC5986049 DOI: 10.1002/ccr3.1499] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 02/03/2018] [Accepted: 02/23/2018] [Indexed: 01/03/2023] Open
Abstract
Congenital erythrocytosis is a hereditary disorder due to an increase in red cell mass that can be caused by mutations in proteins involved in HIF-α pathway, as PHD2. Hereby, we describe a new familial mutation in PHD2 gene. Considering an increased thrombotic potential, patients began antiplatelet aggregation therapy and phlebotomies.
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Affiliation(s)
- João Barradas
- Centro Hospitalar de Tondela‐ViseuEPE – Serviço de Hematologia ClínicaCoimbraPortugal
| | | | - Gisela Ferreira
- Centro Hospitalar do Baixo VougaEPE – Serviço de Hematologia ClínicaViseuPortugal
| | - Paula Rocha
- Centro Hospitalar de Tondela‐ViseuEPE – Serviço de Hematologia ClínicaCoimbraPortugal
| | - Conceição Constanço
- Centro Hospitalar de Tondela‐ViseuEPE – Serviço de Hematologia ClínicaCoimbraPortugal
| | - Maria Reis Andrade
- Centro Hospitalar de Tondela‐ViseuEPE – Serviço de Hematologia ClínicaCoimbraPortugal
| | - Celeste Bento
- Centro Hospitalar e Universitário de CoimbraEPE – Serviço de Hematologia ClínicaCoimbraPortugal
| | - Helena Matos Silva
- Centro Hospitalar de Tondela‐ViseuEPE – Serviço de Hematologia ClínicaCoimbraPortugal
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18
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Camps C, Petousi N, Bento C, Cario H, Copley RR, McMullin MF, van Wijk R, Ratcliffe PJ, Robbins PA, Taylor JC. Gene panel sequencing improves the diagnostic work-up of patients with idiopathic erythrocytosis and identifies new mutations. Haematologica 2016; 101:1306-1318. [PMID: 27651169 PMCID: PMC5394871 DOI: 10.3324/haematol.2016.144063] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 07/26/2016] [Indexed: 12/31/2022] Open
Abstract
Erythrocytosis is a rare disorder characterized by increased red cell mass and elevated hemoglobin concentration and hematocrit. Several genetic variants have been identified as causes for erythrocytosis in genes belonging to different pathways including oxygen sensing, erythropoiesis and oxygen transport. However, despite clinical investigation and screening for these mutations, the cause of disease cannot be found in a considerable number of patients, who are classified as having idiopathic erythrocytosis. In this study, we developed a targeted next-generation sequencing panel encompassing the exonic regions of 21 genes from relevant pathways (~79 Kb) and sequenced 125 patients with idiopathic erythrocytosis. The panel effectively screened 97% of coding regions of these genes, with an average coverage of 450×. It identified 51 different rare variants, all leading to alterations of protein sequence, with 57 out of 125 cases (45.6%) having at least one of these variants. Ten of these were known erythrocytosis-causing variants, which had been missed following existing diagnostic algorithms. Twenty-two were novel variants in erythrocytosis-associated genes (EGLN1, EPAS1, VHL, BPGM, JAK2, SH2B3) and in novel genes included in the panel (e.g. EPO, EGLN2, HIF3A, OS9), some with a high likelihood of functionality, for which future segregation, functional and replication studies will be useful to provide further evidence for causality. The rest were classified as polymorphisms. Overall, these results demonstrate the benefits of using a gene panel rather than existing methods in which focused genetic screening is performed depending on biochemical measurements: the gene panel improves diagnostic accuracy and provides the opportunity for discovery of novel variants.
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Affiliation(s)
- Carme Camps
- National Institute for Health Research (NIHR) Comprehensive Biomedical Research Centre, Oxford, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, UK
| | - Nayia Petousi
- Nuffield Department of Medicine, University of Oxford, UK
| | - Celeste Bento
- Hematology Department, Centro Hospitalar e Universitário de Coimbra, Portugal
| | - Holger Cario
- Department of Pediatrics and Adolescent Medicine, University Medical Center, Ulm, Germany
| | - Richard R Copley
- National Institute for Health Research (NIHR) Comprehensive Biomedical Research Centre, Oxford, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, UK
| | | | | | | | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, UK
| | - Jenny C Taylor
- National Institute for Health Research (NIHR) Comprehensive Biomedical Research Centre, Oxford, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, UK
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19
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Erythrocytosis due to PHD2 Mutations: A Review of Clinical Presentation, Diagnosis, and Genetics. Case Rep Hematol 2016; 2016:6373706. [PMID: 27034858 PMCID: PMC4789426 DOI: 10.1155/2016/6373706] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 02/08/2016] [Accepted: 02/10/2016] [Indexed: 12/17/2022] Open
Abstract
The association of mutations in the PHD2 protein of the hypoxia-sensing pathway and erythrocytosis has only been established in the last decade. Here we report the case of a novel PHD2 gene mutation in a patient with erythrocytosis and summarize all reported cases to date. Case Report. A 55-year-old man presented with dyspnea and a previous diagnosis of idiopathic erythrocytosis. PHD gene sequencing revealed a mutation on exon 2. The mutation was recognized as p.(Trp334⁎) (c. 1001G>A) resulting in a truncation of a highly conserved amino acid residue in catalytic domain. A diagnosis of erythrocytosis secondary to mutant PHD2 gene was made. Conclusions. Our findings indicate that with PHD2 mutations there is moderate erythrocytosis and erythropoietin (Epo) levels are generally low to normal. Two patients with PHD2 substitution mutations were found to have paraganglioma and one of these patients had a concurrent pheochromocytoma. In addition, one mutation was associated with sagittal sinus thrombosis. Given the severity of some of the clinical features of these mutations, we conclude that clinical guidelines should include the PHD2 mutation in the idiopathic erythrocytosis workup.
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20
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Idiopathic erythrocytosis: a study of a large cohort with a long follow-up. Ann Hematol 2015; 95:233-7. [PMID: 26547864 DOI: 10.1007/s00277-015-2548-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 11/03/2015] [Indexed: 12/17/2022]
Abstract
Idiopathic erythrocytosis (IE) is an absolute erythrocytosis with no known cause, diagnosed by exclusion of primary and secondary erythrocytosis. Familial erythrocytosis (FE) is a rare disease and as the rare patients with JAK2-wild-type polycythemia vera (PV) may be misdiagnosed as IE. We compared 78 patients with IE, 21 with FE and 136 with PV in the effort to identify simple features capable of discriminating between them. FE patients were younger at diagnosis either than IE and PV (p < 0.001); IE and FE had lower WBC, platelet counts and higher serum EPO levels, and had splenomegaly and thrombotic events less frequently than PV patients. Phlebotomies to obtain a haematocrit lower than 45 % induce platelet count increase in 70 % of PV but not in IE. Mainly in men, normal spleen, normal platelet counts and no history of thrombosis at diagnosis argue against PV; diagnosis of IE could be supported by means of a cycle of venesection to see how it affects their platelet count. No simple data capable of distinguishing between IE and FE were identified; therefore, a case of sporadic erythrocytosis in a young patient should be investigated as a possible genetic cause.
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21
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Lee G, Arcasoy MO. The clinical and laboratory evaluation of the patient with erythrocytosis. Eur J Intern Med 2015; 26:297-302. [PMID: 25837692 DOI: 10.1016/j.ejim.2015.03.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 03/14/2015] [Accepted: 03/16/2015] [Indexed: 12/19/2022]
Abstract
Erythrocytosis is frequently encountered as an incidental abnormality on laboratory testing that reveals persistent elevation of the hematocrit level (>52% in men and >48% in women). In many cases, erythrocytosis is the manifestation of an underlying cardiopulmonary process, drug-induced due to androgens, or secondary to smoking, rather than a primary bone marrow disorder such as polycythemia vera. A systematic approach to the clinical and laboratory evaluation of each patient is indicated to consider diverse differential diagnosis possibilities and to identify the underlying etiology of erythrocytosis in order to formulate appropriate subspecialist referral and management plans. A thorough medical history and meticulous physical examination supplemented by a focused initial laboratory evaluation will enable the general practitioner to ascertain the etiology of erythrocytosis in the majority of cases. Patients with clinical and laboratory features suggestive of polycythemia vera and those patients without an apparent underlying condition known to cause erythrocytosis benefit from early referral to a hematologist for further specialized diagnostic evaluation and therapy considerations.
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Affiliation(s)
- Grace Lee
- Division of Hematology, Department of Medicine, Duke Cancer Institute, Duke University School of Medicine, Durham, NC, USA
| | - Murat O Arcasoy
- Division of Hematology, Department of Medicine, Duke Cancer Institute, Duke University School of Medicine, Durham, NC, USA.
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22
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Griesshammer M, Gisslinger H, Mesa R. Current and future treatment options for polycythemia vera. Ann Hematol 2015; 94:901-10. [PMID: 25832853 PMCID: PMC4420843 DOI: 10.1007/s00277-015-2357-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/17/2015] [Indexed: 12/22/2022]
Abstract
Patients with polycythemia vera (PV), a myeloproliferative neoplasm characterized by an elevated red blood cell mass, are at high risk of vascular and thrombotic complications and have reduced quality of life due to a substantial symptom burden that includes pruritus, fatigue, constitutional symptoms, microvascular disturbances, and bleeding. Conventional therapeutic options aim at reducing vascular and thrombotic risk, with low-dose aspirin and phlebotomy as first-line recommendations for patients at low risk of thrombotic events and cytoreductive therapy (usually hydroxyurea or interferon alpha) recommended for high-risk patients. However, long-term effective and well-tolerated treatments are still lacking. The discovery of mutations in Janus kinase 2 (JAK2) as the underlying molecular basis of PV has led to the development of several targeted therapies, including JAK inhibitors, and results from the first phase 3 clinical trial with a JAK inhibitor in PV are now available. Here, we review the current treatment landscape in PV, as well as therapies currently in development.
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23
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Chauveau A, Luque Paz D, Lecucq L, Le Gac G, Le Maréchal C, Gueguen P, Berthou C, Ugo V. A new point mutation in EPOR inducing a short deletion in congenital erythrocytosis. Br J Haematol 2015; 172:475-7. [PMID: 26010769 DOI: 10.1111/bjh.13511] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Aurélie Chauveau
- CHU Brest, Laboratoire d'Hématologie, Brest, France.,Université de Brest, UFR Médecine, Brest, France.,INSERM U1078, Brest, France
| | - Damien Luque Paz
- CHU Brest, Laboratoire d'Hématologie, Brest, France.,INSERM U1078, Brest, France
| | - Lydie Lecucq
- CHU Brest, Laboratoire d'Hématologie, Brest, France.,Plateforme INCa de Génétique Hospitalière des Cancers de Brest, Brest, France
| | - Gérald Le Gac
- Université de Brest, UFR Médecine, Brest, France.,INSERM U1078, Brest, France.,CHU Brest, Laboratoire de Génétique, Brest, France
| | - Cédric Le Maréchal
- Université de Brest, UFR Médecine, Brest, France.,INSERM U1078, Brest, France.,CHU Brest, Laboratoire de Génétique, Brest, France
| | - Paul Gueguen
- Université de Brest, UFR Médecine, Brest, France.,INSERM U1078, Brest, France.,CHU Brest, Laboratoire de Génétique, Brest, France
| | - Christian Berthou
- Université de Brest, UFR Médecine, Brest, France.,CHU Brest, Service d'Hématologie, Institut de Cancérologie et d'Hématologie, Brest, France
| | - Valérie Ugo
- CHU Brest, Laboratoire d'Hématologie, Brest, France. .,Université de Brest, UFR Médecine, Brest, France. .,INSERM U1078, Brest, France.
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24
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Tamura S, Tamura T, Gima H, Nishikawa A, Okamoto Y, Kanazawa N, Relvas L, Cunha E, Frances McMullin M, Bento C. A Japanese Family with Congenital Erythrocytosis Caused by Haemoglobin Bethesda. Intern Med 2015; 54:2389-93. [PMID: 26370867 DOI: 10.2169/internalmedicine.54.4520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We herein present a case of congenital erythrocytosis caused by haemoglobin (Hb) Bethesda in a Japanese family. A 55-year-old asymptomatic man was referred to our hospital for the investigation of erythrocytosis, which was present in other members of his family. The patient's serum erythropoietin level was normal, and the JAK2 V617F mutation was not detected. His P50 value was mildly decreased, thus we suspected the presence of an Hb variant with a high oxygen affinity. The high-performance liquid chromatography analysis showed an abnormal Hb, and by direct sequencing we identified the Hb Bethesda variant in this patient. For the differential diagnosis, we recommend the estimation of the P50 value as a practical and useful test.
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Affiliation(s)
- Shinobu Tamura
- Department of Hematology and Oncology, Kinan Hospital, Japan
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25
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The high oxygen affinity haemoglobin Nantes: a family case description. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2014; 13:524-7. [PMID: 25545870 DOI: 10.2450/2014.0206-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 10/07/2014] [Indexed: 11/21/2022]
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26
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Gardie B, Percy MJ, Hoogewijs D, Chowdhury R, Bento C, Arsenault PR, Richard S, Almeida H, Ewing J, Lambert F, McMullin MF, Schofield CJ, Lee FS. The role of PHD2 mutations in the pathogenesis of erythrocytosis. HYPOXIA 2014; 2:71-90. [PMID: 27774468 PMCID: PMC5045058 DOI: 10.2147/hp.s54455] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The transcription of the erythropoietin (EPO) gene is tightly regulated by the hypoxia response pathway to maintain oxygen homeostasis. Elevations in serum EPO level may be reflected in an augmentation in the red cell mass, thereby causing erythrocytosis. Studies on erythrocytosis have provided insights into the function of the oxygen-sensing pathway and the critical proteins involved in the regulation of EPO transcription. The α subunits of the hypoxia-inducible transcription factor are hydroxylated by three prolyl hydroxylase domain (PHD) enzymes, which belong to the iron and 2-oxoglutarate-dependent oxygenase superfamily. Sequence analysis of the genes encoding the PHDs in patients with erythrocytosis has revealed heterozygous germline mutations only occurring in Egl nine homolog 1 (EGLN1, also known as PHD2), the gene that encodes PHD2. To date, 24 different EGLN1 mutations comprising missense, frameshift, and nonsense mutations have been described. The phenotypes associated with the patients carrying these mutations are fairly homogeneous and typically limited to erythrocytosis with normal to elevated EPO. However, exceptions exist; for example, there is one case with development of concurrent paraganglioma (PHD2-H374R). Analysis of the erythrocytosis-associated PHD2 missense mutations has shown heterogeneous results. Structural studies reveal that mutations can affect different domains of PHD2. Some are close to the hypoxia-inducible transcription factor α/2-oxoglutarate or the iron binding sites for PHD2. In silico studies demonstrate that the mutations do not always affect fully conserved residues. In vitro and in cellulo studies showed varying effects of the mutations, ranging from mild effects to severe loss of function. The exact mechanism of a potential tumor-suppressor role for PHD2 still needs to be elucidated. A knockin mouse model expressing the first reported PHD2-P317R mutation recapitulates the phenotype observed in humans (erythrocytosis with inappropriately normal serum EPO levels) and demonstrates that haploinsufficiency and partial deregulation of PHD2 is sufficient to cause erythrocytosis.
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Affiliation(s)
- Betty Gardie
- Laboratoire de Génétique Oncologique de l'Ecole Pratique des Hautes Etudes, Villejuif; Unité Mixte de Recherche, Institut national de la santé et de la recherche médicale U892, Centre national de la recherche scientifique 6299, Centre de Recherche en Cancérologie Nantes/Angers, Université de Nantes, Nantes, France
| | - Melanie J Percy
- Department of Haematology, Belfast City Hospital, Belfast, UK
| | - David Hoogewijs
- Institute of Physiology and Zürich Center for Integrative Human Physiology, University of Zürich, Zürich, Switzerland
| | - Rasheduzzaman Chowdhury
- Department of Chemistry and Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Celeste Bento
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Patrick R Arsenault
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Stéphane Richard
- Laboratoire de Génétique Oncologique de l'Ecole Pratique des Hautes Etudes, Villejuif; Institut national de la santé et de la recherche médicale U753, Institut de cancérologie Gustave Roussy (IGR), Villejuif, France; Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France
| | - Helena Almeida
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | | | - Frédéric Lambert
- Center for Human Genetics, Pathology Institute, UniLab-Lg, Molecular Haemato-Oncology Unit, CHU of Liege, Liege, Belgium
| | | | - Christopher J Schofield
- Department of Chemistry and Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Frank S Lee
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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27
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Jang JH, Seo JY, Jang J, Jung CW, Lee KO, Kim SH, Kim HJ. Hereditary gene mutations in Korean patients with isolated erythrocytosis. Ann Hematol 2014; 93:931-5. [PMID: 24482100 DOI: 10.1007/s00277-014-2006-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 01/03/2014] [Indexed: 02/02/2023]
Abstract
Most cases of erythrocytosis occur secondary to chronic tissue hypoxia or as a clonal disease such as polycythemia vera with somatic mutations in the Janus kinase 2 (JAK2) gene. Rarely, erythrocytosis is caused by hereditary gene mutations. This study investigated hereditary gene mutations in 38 unrelated Korean patients with isolated erythrocytosis without (1) JAK2 mutation and (2) secondary causes of erythrocytosis other than smoking history. Direct sequencing analyses were performed on six genes associated with hereditary erythrocytosis [HBB, exon 2 and exon 3 of HBA2, VHL, EGLN1 (previously PHD2), exon 12 of EPAS1 (previously HIF2A), and exons 5-8 of EPOR]. As a result, mutations were detected in five patients (three never smokers and two current smokers) out of 38 patients (13.2 %). The mutations detected in those five patients were EPOR:p.W439*, EPOR:p.G212C, HBB:p.H98Q (or conventionally H97Q, Hb Malmö [β 97(FG4) His > Gln]), HBB:p.V138M (V137M), and EGLN1:p.L279Tfs43*, all in heterozygous state. No patient had mutations in HBA2, VHL, or in EPAS1. This study indicates that workup for hereditary gene mutations is needed for isolated erythrocytosis with or without smoking history.
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Affiliation(s)
- Ja-Hyun Jang
- Department of Laboratory Medicine & Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul, South Korea, 135-710
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28
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Cario H, McMullin MF, Bento C, Pospisilova D, Percy MJ, Hussein K, Schwarz J, Aström M, Hermouet S. Erythrocytosis in children and adolescents-classification, characterization, and consensus recommendations for the diagnostic approach. Pediatr Blood Cancer 2013; 60:1734-8. [PMID: 23776154 DOI: 10.1002/pbc.24625] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 05/16/2013] [Indexed: 11/11/2022]
Abstract
During recent years, the increasing knowledge of genetic and physiological changes in polycythemia vera (PV) and of different types of congenital erythrocytosis has led to fundamental changes in recommendations for the diagnostic approach to patients with erythrocytosis. Although widely accepted for adult patients this approach may not be appropriate with regard to children and adolescents affected by erythrocytosis. The "congenital erythrocytosis" working group established within the framework of the MPN&MPNr-EuroNet (COST action BM0902) addressed this question in a consensus finding process and developed a specific algorithm for the diagnosis of erythrocytosis in childhood and adolescence which is presented here.
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Affiliation(s)
- Holger Cario
- Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
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29
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Spolverini A, Pieri L, Guglielmelli P, Pancrazzi A, Fanelli T, Paoli C, Bosi A, Nichele I, Ruggeri M, Vannucchi AM. Infrequent occurrence of mutations in the PH domain of LNK in patients with JAK2 mutation-negative 'idiopathic' erythrocytosis. Haematologica 2013; 98:e101-2. [PMID: 23812944 DOI: 10.3324/haematol.2013.090175] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Fujita H, Hamaki T, Handa N, Ohwada A, Tomiyama J, Nishimura S. Hypocholesterolemia in patients with polycythemia vera. J Clin Exp Hematop 2013; 52:85-9. [PMID: 23037623 DOI: 10.3960/jslrt.52.85] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Polycythemia vera (PV) is characterized by low serum total cholesterol despite its association with vascular events such as myocardial and cerebral infarction. Serum cholesterol level has not been used as a diagnostic criterion for PV since the 2008 revision of the WHO classification. Therefore, we revisited the relationship between serum lipid profile, including total cholesterol level, and erythrocytosis. The medical records of 34 erythrocytosis patients (hemoglobin : men, > 18.5 g/dL ; women, > 16.5 g/dL) collected between August 2005 and December 2011 were reviewed for age, gender, and lipid profiles. The diagnoses of PV and non-PV erythrocytosis were confirmed and the in vitro efflux of cholesterol into plasma in whole blood examined. The serum levels of total cholesterol, low-density-lipoprotein cholesterol (LDL-Ch), and apolipoproteins A1 and B were lower in PV than in non-PV patients. The in vitro release of cholesterol into the plasma was greater in PV patients than in non-PV and non-polycythemic subjects. Serum total cholesterol, LDL-Ch, and apolipoproteins A1 and B levels are lower in patients with PV than in those with non-PV erythrocytosis. The hypocholesterolemia associated with PV may be attributable to the sequestration of circulating cholesterol into the increased number of erythrocytes.
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Affiliation(s)
- Hiroshi Fujita
- Department of Transfusion Medicine, Tokyo Metropolitan Bokutoh Hospital, Tokyo, Japan.
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31
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Choe WH, Park BG, Lee KH, Lee JH, Lee JH, Kwon SW. Automated double red-cell phlebotomy for the treatment of erythrocytosis. J Clin Apher 2012; 27:255-9. [DOI: 10.1002/jca.21241] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 06/14/2012] [Indexed: 01/19/2023]
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32
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Renal transplantation in patients with familial Mediterranean fever. Clin Rheumatol 2012; 31:1183-6. [DOI: 10.1007/s10067-012-1992-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2012] [Accepted: 04/18/2012] [Indexed: 10/28/2022]
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33
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Hussein K, Percy M, McMullin MF. Clinical utility gene card for: familial erythrocytosis. Eur J Hum Genet 2012; 20:ejhg2011252. [PMID: 22274579 DOI: 10.1038/ejhg.2011.252] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Kais Hussein
- Institute of Pathology, Hannover Medical School, Hannover, Germany.
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Fujita H, Hamaki T, Ohwada A, Tomiyama J, Nishimura S. Serum levels of granulocyte colony-stimulating factor in JAK2 V617F -positive vs. negative erythrocytosis. Int J Lab Hematol 2011; 33:e20-1. [DOI: 10.1111/j.1751-553x.2011.01336.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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35
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Albiero E, Ruggeri M, Fortuna S, Finotto S, Bernardi M, Madeo D, Rodeghiero F. Isolated erythrocytosis: study of 67 patients and identification of three novel germ-line mutations in the prolyl hydroxylase domain protein 2 (PHD2) gene. Haematologica 2011; 97:123-7. [PMID: 21828119 DOI: 10.3324/haematol.2010.039545] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The oxygen sensing pathway modulates erythropoietin expression. In normal cells, intracellular oxygen tensions are directly sensed by prolyl hydroxylase domain (PHD)-containing proteins. PHD2 isozyme has a key role in tagging hypoxia-inducible factor (HIF)-α subunits for polyubiquitination and proteasomal degradation. Erythrocytosis-associated PHD2 mutations reduce hydroxylation of HIF-α. The investigation of 67 patients with isolated erythrocytosis, either sporadic or familial, allowed the identification of three novel mutations in the catalytic domain of the PHD2 protein. All new mutations are germ-line, heterozygous and missense, and code for a predicted full length mutant PHD2 protein. Identification of the disease-causing genes will be of critical importance for a better classification of familial and acquired erythrocytosis, offering additional insight into the erythropoietin regulating oxygen sensing pathway.
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Affiliation(s)
- Elena Albiero
- Department of Cellular Therapies and Haematology, San Bortolo Hospital, Vicenza, Italy
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