The significance of detection of CD59 in the diagnosis of paroxysmal nocturnal hemoglobinuria

Objective To explore the clinical significance of detection of CD59 in the diagnosis of PNH and AA PNH syndrome. Methods The expression of CD59 was detected in RBCs and polymorphonuclear neutrophils (PMNs) from peripheral blood of 13 PNH (including 2 cases of AA PNH syndrome ) and 37 AA patients by flow cytometry along with FITC labelled anti CD59 monoclonal antibody. Results The positive rates of CD59 expression were constantly more than 98% in RBCs and PMNs from normal individuals,whereas less than 90% in RBCs and PMNs from the 13 PNH patients. Of the 37 AA patients, the positive rates of CD59 expression were normal in RBCs and PMNs from 24 cases but decreased to a greater or lesser degree in RBCs or PMNs from 13 cases compared with that in normal individuals. Conclusion Determination of CD59 in peripheral RBCs and PMNs could be considered a direct, specific and sensitive method for the diagnosis of PNH, especially in PNH with atypical manifestations and AA PNH syndrome.