a condition where the body does not have enough red blood cells and therefore has a lower ability to carry oxygen to vital organs. This may lead to fatigue and other symptoms such as breathlessness, palpitations, light headedness and a pale complexion.
an immune disorder where the bone marrow does not produce enough healthy blood cells including red blood cells, white blood cells and platelets. It is not uncommon for PNH patients to also have aplastic anaemia as well.
This is part of the immune system that destroys bacteria and other foreign cells. In PNH, the complement is responsible for the destruction of red blood cells that lack the protective GPI anchor proteins.
Red, dark or black urine caused by the presence of free haemoglobin in the urine. The free haemoglobin is a result of the destruction of red blood cells by the complement part of the immune system which causes the red blood cells to burst. When the red cells burst, this releases haemoglobin into the blood plasma which overflows through the kidneys into the urine. This is different from “haematuria” which is bleeding into the urine.
This is an enzyme which is found in the blood and other body tissues. One of the things that can cause LDH levels to be raised is the destruction of red blood cells. Therefore LDH levels are an extremely useful marker of haemolysis. LDH levels usually reduce significantly after a patient has started treatment with eculizumab.
This is an infection caused by the bacterium Neisseria meningitidis (also called meningococcus). This bacterium can cause meningitis or widespread blood infection (sepsis). A fully functioning terminal complement system (part of the immune system) is necessary to prevent this infection.
These are the blood cells that are involved in blood clotting. Low platelet counts are associated with increased bleeding and bruising. Activated or stimulated platelets can clump together in the wrong place leading to the formation of blood clots or thrombosis.
The group of cells in the body that are affected by the genetic defect that causes PNH. These cells all come from the same parent cell in the bone marrow. Since the genetic defect lies in the parent cell, all cells which come from the parent cell, (including red blood cells, white blood cells and platelets) are affected. The size of a PNH clone depends on the number of cells affected by PNH. A PNH clone is tested on a regular basis in order to identify whether a PNH clone has increased, decreased or is stable.
The formation or development of a blood clot that often blocks blood from flowing through a vessel. In PNH, blood clots can occur in common places (leg veins and lungs) but can also occur in unusual places such as in vessels in the abdomen and brain.
This is an anticoagulant normally used in the prevention of blood clots. Due to the high risk of blood clots in PNH, preventative treatment with warfarin can potentially decrease the risk of blood clots.