title: [Vascular myeloproliferative neoplasm with normal cell blood count: Exploration and medical management].
abstract: Negative BCR ABL myeloproliferative neoplasm (MPN) such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (MFP) are clonal hematological malignancies and may lead to a high risk of venous, arterial or microcirculatory thrombosis. Atypical sites of thrombosis can sometimes reveal the neoplasm disorder. Their diagnoses are a major issue because of the propensity to develop acute myeloid leukemia and/or myelofibrosis. The acquired JAK2V617F variant (Janus kinase 2; 9p24) is a prevalent MPN and also a sensitive marker for PV diagnosis (95% positive mutation), but not specific since found in approximately 50% of patients with ET and MFP.
  
  
  METHODS
  We present a diagnostic and a therapeutic approach based on one patient with microcirculatory ischemic manifestations in the toes, and who had strictly normal cell blood counts and was positive for JAK2V617F mutation: thrombotic risk factor evaluation; bone marrow biopsy; red cell adhesion assays. These experimental assays are promising for the development of new therapeutics in MPN; they assess red cell adherence to the vascular endothelium after the phosphorylation of Lu/BCAM subsequent to a positive JAK2V617F mutation.
  
  
  RESULTS
  Compared with controls, our patient exhibited increased Lu/BCAM receptor phosphorylation and red blood cell adhesion.
  
  
  CONCLUSIONS
  This development may lead to improved care for patients with thrombotic manifestations, normal blood cell counts, and a positive JAK2V617F mutation: multidisciplinary management, including regular hematological monitoring, could lead to the introduction of a cytoreductive treatment.
authors.affiliation: Service de médecine vasculaire, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75674 Paris cedex 14, France. Electronic address: caroline.fourgeaud@gmail.com.
authors.forename: C
authors.initials: C
authors.lastname: Fourgeaud
authors.affiliation: Institut national de la transfusion sanguine, Inserm U1134, 6, rue Alexandre-Cabanel, 75739 Paris cedex 15, France.
authors.forename: W
authors.initials: W
authors.lastname: El Nemer
authors.affiliation: Service de médecine vasculaire, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75674 Paris cedex 14, France.
authors.forename: U
authors.initials: U
authors.lastname: Michon Pasturel
authors.affiliation: Service de médecine vasculaire, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75674 Paris cedex 14, France.
authors.forename: S
authors.initials: S
authors.lastname: Bonhomme
authors.affiliation: Service d'hématologie A, hôpital Necker, 149, rue de Sèvres, 75015 Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Brignier
authors.affiliation: Service de médecine vasculaire, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75674 Paris cedex 14, France.
authors.forename: I
authors.initials: I
authors.lastname: Lazareth
authors.affiliation: Service de médecine vasculaire, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75674 Paris cedex 14, France.
authors.forename: P
authors.initials: P
authors.lastname: Priollet
mesh_terms: D000368:Aged; D001772:Blood Cell Count; D001853:Bone Marrow / Q000473:pathology; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D015897:Comorbidity; D003937:Diagnosis, Differential; D017700:Embolism, Cholesterol / Q000175:diagnosis; D004730:Endothelium, Vascular / Q000473:pathology; D004912:Erythrocytes / Q000473:pathology; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D006918:Hydroxyurea / Q000627:therapeutic use; D007511:Ischemia / Q000209:etiology; D053614:Janus Kinase 2 / Q000235:genetics / Q000378:metabolism; D007797:Laminin / Q000378:metabolism; D008188:Lutheran Blood-Group System / Q000378:metabolism*; D008297:Male; D008833:Microcirculation; D020125:Mutation, Missense; D009196:Myeloproliferative Disorders / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics; D010766:Phosphorylation; D017354:Point Mutation; D011499:Protein Processing, Post-Translational; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D019851:Thrombophilia / Q000209:etiology; D014034:Toes / Q000098:blood supply
chemical_list: C090228:BCAM protein, human; D015815:Cell Adhesion Molecules; D007797:Laminin; D008188:Lutheran Blood-Group System; C507924:JAK2 protein, human; D053614:Janus Kinase 2; D006918:Hydroxyurea
keywords: Adhesion assay; JAK2V617F; Mutation JAK2V617F; Tests d’adhérence