Canterbury DHB
PNH is a rare disease and may present in a number of different ways. There is often a delay in establishing the diagnosis, mainly because the possibility of PNH is not considered.
A chronic haemolytic anaemia with dark, early morning urine is characteristic but only occurs in a minority of patients. Iron deficiency, due to urinary iron loss, may occur. Other patients may present with pancytopenia and have symptoms secondary to anaemia, neutropenia, or thrombocytopenia. Patients may also present with thrombosis, often of large vessels such as hepatic vein thrombosis or thrombosis of the cerebral veins or sinuses. Headaches or abdominal pain occurring in a patient with PNH may be signs of these major thrombotic events. Aplastic Anaemia (AA) may present both before and after the PNH defect has been diagnosed. 20% of new patients with AA may have a PNH clone. Some studies have also found that 20% of new patients with MDS have a PNH clone.
Topic Code: 4935