Immunophenotyping of Paroxysmal Nocturnal Hemoglobinuria (PNH)

: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare but often debilitating disease which may lead to death in up to 35% of patients within 5 years if unrecognized and untreated. Detection of PNH and assessment of PNH clone size in RBC and WBC lineages by flow cytometric analysis has increased in importance due to the availability of novel therapies. These therapies typically block the hemolysis of red blood cells and thus significantly lower the morbidities and mortality associated with this disease. This chapter describes validated, state-of-the-art, high-sensitivity flow cytometric methodologies based on latest published testing guidelines for PNH.