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What is PNH?

Paroxysmal Nocturnal Hemoglobinuria (PNH): A progressive, life-threatening disease that causes thrombosis, end organ damage and impaired quality of life1-3

PNH Red Blood Cell (RBC)

Complement Attack

PNH RBC Lysis (Hemolysis)

PNH is an acquired disease that leads to the hemolysis of red blood cells due to uncontrolled complement activation1,2,5

  • PNH is caused by an acquired somatic mutation of the PIG-A gene which leads to a lack of glycosylphosphatidylinositol-linked surface proteins, including the complement regulatory proteins CD55 and CD59
  • RBCs deficient in CD55 and CD59 are susceptible to chronic intravascular complement-mediated hemolysis
  • Hemolysis leads to the release of hemoglobin and nitric oxide scavenging, both of which are involved in the underlying consequences of PNH
  • Chronic complement-mediated hemolysis is the underlying cause of progressive morbidities and mortality in PNH

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  1. Santarone S, Bacigalupo A, Risitano AM, et al. Hematopoietic stem cell transplantation for paroxysmal nocturnal hemoglobinuria: long-term results of a retrospective study on behalf of the Gruppo Italiano Trapianto Midollo Osseo (GITMO). Haematologica. 2010;95:983-988.
  2. Borowitz MJ, Craig FE, DiGiuseppe JA, et al. On behalf of the Clinical Cytometry Society. Guidelines for the diagnosis and monitoring of PNH and related disorders by flow cytometry. Cytometry Part B Clin Cytom. 2010;78B:211-230.
  3. Richards SJ, Barnett D. The role of flow cytometry in the diagnosis of PNH in the clinical laboratory. Clin Lab Med. 2007;27:577-590.
  4. Movalia M, Illingworth A, Weitz I, et al. Poster presented at the 53rd Annual Meeting of the American Society of Hematology; December 10-13, 2011; San Diego, CA. Abstract 1033.
  5. Parker C, Omine M, Richards S, et al. for the International PNH Interest Group. Blood. 2005;106:3699-3709.
  6. Dunn DE, Tanawattanacharoen P, Boccuni P, et al. Ann Intern Med. 1999;131:401-408.
  7. Borowitz MJ, Craig FE, DiGiuseppe JA, et al;for Clinical Cytometry Society. Cytometry Part B. 2010;78B:211-230.
  8. Hillmen P, Muus P, Röth A, et al. Br J Haematol. 2013;162:62-73.