Detection Of Paroxysmal Nocturnal Hemoglobinuria Clones In Patients With Pancytopenia.

Paroxysmal nocturnal hemoglobinuria (PNH) clones lack complement regulatory molecules (CD55,CD59) and therefore probably “weakened”, have no malignant potential, occur at low levels in normal individuals. The presence of PNH clones in the setting of aplastic anemia (AA) or myelodysplastic syndrome (MDS) have been shown to have prognostic and therapeutic implications. The current study aimed to detect expression of PNH clones (CD55 and CD59) in patients with pancytopenia by flowcytometric analysis. The study included 48 newly diagnosed pancytopenic patients. Twenty four apparently healthy volunteers' age and sex matched with patients were chosen as control group. Peripheral blood samples were be analyzed by flowcytometry for detection of CD55&CD59. 33.3% of patients having (CD55¯ and CD59¯) were detected, also CD55¯ and CD59¯ were significantly increased in pancytopenic patients with PNH clone subgroup compared to the other two patients subgroups (aplastic anemia and MDS). PNH clone was higher in patients with A.A (40%). than in patients of MDS (22.2%). In conclusion, flowcytometry is a sensitive and reliable method of PNH clone assessment in bone marrow failure syndrome. Our findings confirmed the presence of CD55¯ and CD59¯cell clones in granulocytes of pancytopenic patients who diagnosed as A.A and MDS. This suggests that these disorders may be part of bone marrow failure syndrome. The assessment of PNH clone may be important for monitoring therapy. This needs to be confirmed with further studies on larger cohorts of patients