title: Detection of CD55- and/or CD59-deficient red cell populations in patients with plasma cell dyscrasias.
abstract: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disorder characterized by a decrease or absence of glycosylphosphatidylinositol (GPI)-anchored molecules such as CD55 and CD59 from the surface of affected cells, resulting in intravascular hemolysis, cytopenia, and venous thrombosis. A PNH-like phenotype has been detected in various hematological disorders, mainly in aplastic anemia and myelodysplastic syndromes, but also in lymphoproliferative syndromes (LPSs). To the best of our knowledge, CD55- or CD59-deficient red cells have not been detected in plasma cell dyscrasias (PCDs). The aim of this study was the detection of CD55- and/or CD59-deficient red cell populations in patients with PCD. Seventy-seven patients were evaluated; 62 with multiple myeloma (MM), 7 with Waldenstrom macroglobulinemia (WM), 6 with monoclonal gammopathy of undetermined significance (MGUS), and 2 with heavy chain disease (HCD). The sephacryl gel microtyping system was applied; Ham and sucrose lysis tests were also performed on all samples with CD55- or CD59-negative populations. Red cells deficient in both molecules were detected in 10 (12.9%) of 77 patients with PCD: 2 (28.6%) of 7 with WM, 1 (16.6%) of 6 with MGUS, 6 (9.6%) of 62 with MM, and 1 of 2 patients with HCD. Isolated CD55 deficiency was found in 28.5% of all PCD patients, whereas isolated CD59 deficiency was not observed in any patients. These findings illustrate the existence of the PNH phenotype in the red cells of patients with PCD; further investigation is needed into the mechanisms and significance of this phenotype.
authors.affiliation: First Department of Internal Medicine, University of Athens School of Medicine, Laiko General Hospital, Greece. imeletis@cc.uoa.gr
authors.forename: John
authors.initials: J
authors.lastname: Meletis
authors.forename: Evangelos
authors.initials: E
authors.lastname: Terpos
authors.forename: Michalis
authors.initials: M
authors.lastname: Samarkos
authors.forename: Christos
authors.initials: C
authors.lastname: Meletis
authors.forename: Effie
authors.initials: E
authors.lastname: Apostolidou
authors.forename: Veroniki
authors.initials: V
authors.lastname: Komninaka
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Korovesis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Anargyrou
authors.forename: Olga
authors.initials: O
authors.lastname: Benopoulou
authors.forename: Despina
authors.initials: D
authors.lastname: Mavrogianni
authors.forename: Eleni
authors.initials: E
authors.lastname: Variami
authors.forename: Nora
authors.initials: N
authors.lastname: Viniou
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Konstantopoulos
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018958:CD55 Antigens / Q000032:analysis*; D018957:CD59 Antigens / Q000032:analysis*; D004910:Erythrocyte Membrane / Q000737:chemistry*; D005260:Female; D006362:Heavy Chain Disease / Q000097:blood; D006386:Hemagglutination Tests; D006457:Hemoglobinuria, Paroxysmal / Q000097:blood; D006461:Hemolysis; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D008297:Male; D008832:Microchemistry; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood; D010265:Paraproteinemias / Q000097:blood*; D008258:Waldenstrom Macroglobulinemia / Q000097:blood
chemical_list: D018958:CD55 Antigens; D018957:CD59 Antigens