
Introduction and Key Points
PNH is an extremely rare condition, but it is important because of the insights it provides into the haematopoietic and complement systems. This acquired clonal stem cell abnormality has an association with AA as well as MDS and AML. It predisposes to thrombosis. For a recent review of PNH, see Rosse et al.
Key Points
- PNH is an acquired disorder of the haematopoietic stem cell and blood cells circulate lacking CD 55 and 59.
- Patients may present with haemolytic anaemia, cytopenias, thromboses, or all three.
- Flow cytometry of red cells to detect the absence of CD 55 and 59 establishes the diagnosis.
- Treatment is largely supportive, but allografting may be justified in severe cases or if MDS/AML develops.
- Eculizumab may reduce the severity of haemolysis.
- PNH patients may be eligible for entry into a trial. For current trials, see the Haematology Clinical Trials page on the Haematology Red Book homepage.
Topic Code: 4934