The Role of Flow Cytometry in the Diagnosis of PNH
Screening and diagnosis of patients with PNH has improved with the development of ﬂow cytometry.1 Immunophenotypic analysis of GPI-linked antigen expression on red cells and peripheral blood granulocytes by ﬂow cytometry provides a rapid, sensitive and speciﬁc method for screening and diagnosis of PNH. 2
Traditional laboratory methods for diagnosing PNH are based on proving an increased susceptibility of patient erythrocytes to lysis by complement, activated by acidiﬁcation of serum. Though thistype of testing has been modiﬁed to improve sensitivity and speciﬁcity, ﬂow cytometry is superior as a diagnostic method. Flow cytometry is the gold standard for testing for PNH and is recommended by the International PNH Interest Group.3
Inform Diagnostics and the Use of Quality Flow Cytometry
In concert with guidelines from the International Clinical Cytometry Society (ICCS) and the International PNH Interest Group, Inform Diagnostics provides high-sensitivity ﬂow cytometry testing on peripheral blood for the detection of PNH clones. In accordance with the ICCS guidelines, Inform Diagnostics Life Sciences utilizes informative reagents for ﬂow cytometry, including CD59 and CD235A for red cells and FLAER, CD24, CD16, CD15, CD14, CD33 and CD45 for granulocytes and monocytes. 4
Inform Diagnostics oﬀers high-sensitivity testing to identify and diﬀerentiate blood-based disorders and cancers. In the case of PNH, the ICCS guidelines validate our standard laboratory operations. Our diﬀerence is further validated by being recognized as one of the few laboratories able to perform high-sensitivity ﬂow cytometry for PNH patients by Alexion Pharmaceuticals (the developer of eculizumab (Soliris®) a therapeutic monoclonal antibody for the treatment of PNH).
1 Hall SE, Rosse WF. The use of monoclonal antibodies and ﬂow cytometry in the diagnosis of paroxysmal nocturnal hemoglobinuria. Blood 1996; 87: 5332-40.
2 Richards SJ, Barnett D. The role of ﬂow cytometry in the diagnosis of paroxysmal nocturnal hemoglobinuria in the clinical laboratory. Clin Lab Med. 2007 Sep;27(3):577-90, vii.
3 Parker C, Omine M, Richards S, et al. Diagnosis and management of paroxysmal nocturnal hemoglobinuria. Blood 2005;106(12):3699-4709.
4 Borowitz MJ, Craig Fe, Digiuseppe JA et al; for Clinical Cytometry Society. Guidelines for the diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria and related disorders by ﬂow cytometry. Cytometry Part B Clin Cytometry, 2010; 78B:211-230.
5 Brodsky, RA. How I treat paroxysmal nocturnal hemoglobinuria. Blood 2009;113:6522-6527.