[Detection of CD59(-) blood cells in patients with aplastic anemia].

OBJECTIVE: To detect paroxysmal nocturnal hemoglobinuria (PNH) clone in aplastic anemia (AA) patients. METHODS: Flow cytometric technique along with antibodies against CD59 was used to estimate the amount of GPI-P deficient cells, characteristic of PNH abnormalities. RESULTS: Among 23 cases of AA studied, 13 possessed no excessive percentage of CD59(-) cells in peripheral PMNs and RBCs. Eight of these 13 cases underwent bone marrow examination, and no increase of CD59(-) mononuclear cell (MNC) was found either. Three other AA patients had slightly increased amount (> 5%) of CD59(-) cells in both peripheral blood and bone marrow. In seven cases, percentages of CD59(-) cells were normal in peripheral RBCs and PMNs but increased in bone marrow MNCs. CONCLUSION: Measurement of CD59(-) cells in periperal blood and bone marrow by flow cytometry may serve as the best way of detecting PNH clone in AA, and thus could be used for the early diagnosis of AA-PNH syndrome.