Paroxysmal nocturnal hemoglobinuria (PNH) is a rare and complex blood disease that involves the destruction of red blood cells and can present as anemia, blood clots, and/or bone marrow failure. PNH can lead to life-threatening complications.
In people with PNH, certain red blood cells are destroyed by a part of the immune system called the complement system. This destruction of red blood cells is called hemolysis.
Hemoglobin (Hb) is the protein in your red blood cells that carries oxygen throughout your body. In PNH, as red blood cells are destroyed, hemoglobin levels go down.
One person may have mild symptoms, while another could have severe symptoms and require blood transfusions.
