Last update:
04-Jan-2001

Arch Hellen Med, 17(4), July-August 2000, 383-389

ORIGINAL PAPER

Detection of CD55 and/or CD59 deficient red cell populations
in patients with aplastic anemia and myelodysplastic syndromes

E. TERPOS,¹ M. SAMARKOS,¹ C. MELETIS,² V. KOMNINAKA,¹
E. APOSTOLIDOU,¹ O. BENOPOULOU,¹ K. KOROVESIS,¹ D. MAVROGIANNI,¹
K. ANARGYROU,¹ N. VINIOU,¹ E. VARIAMI,¹ K. KONSTANTOPOULOS,¹ J. MELETIS¹

¹First Department of Internal Medicine, University of Athens, School of Medicine, Laiko General Hospital, Athens
²Department of Electrical and Computer Engineering, National Technical University of Athens, Greece

OBJECTIVE Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal stem cell disorder characterized by intravascular hemolysis, venous thrombosis, marrow hypoplasia, frequent episodes of infection and, rarely, leukemic conversion. At the cellular level PNH is characterized by the decrease or absence of glycosylphosphatidylinositol (GPI)-anchored molecules, such as CD55 and CD59, on the cell surface. Paroxysmal nocturnal hemoglobinuria-like clones have been described in various hematological disorders. The link between PNH and aplastic anemia (AA) is established but the relationship of PNH with myelodysplastic syndromes (MDS) remains unclear.
METHOD In this study the presence of CD55 and/or CD59 defective (PNH-like) red cell populations was evaluated in 19 patients with AA, 118 with MDS and 7 with PNH, and in 121 healthy blood donors, using the sephacryl gel test microtyping system.
RESULTS Red cell populations deficient in both molecules CD55 and CD59 were detected in 36.8% of AA patients, in 17.7% of MDS patients and in all PNH patients. CD55 deficient red cell populations were found in 15.7% of patients with AA and in 12.7% of patients with MDS. CD59 deficient populations were found in 10.5% of patients with AA and in 2.5% of patients with MDS.
CONCLUSIONS These results indicate an association between PNH, AA and MDS. Further investigation is necessary to elucidate the mechanisms of this association, and to define classification criteria for borderline cases, where diagnosis is difficult.

Key words: Aplastic anemia, CD55 (DAF), CD59 (MIRL), GPI-anchor proteins, Myelodysplastic syndromes, Paroxysmal nocturnal hemoglobinuria.