PNH is a rare, serious and life-threatening disease, in which red blood cells are constantly destroyed. The ongoing destruction of red blood cells is called chronic hemolysis.
PNH is an acquired defect in a blood stem cell (a cell in your bone marrow which produces other cells). Since it is acquired, PNH is neither contagious nor hereditary, meaning a person cannot give it to or receive it from someone else.
PNH affects just 8,000-10,000 people in the US and Europe. PNH most often affects adults in the prime of their lives, with the median age at diagnosis in the early 30s.
PNH can result in anemia, requiring blood transfusions, extreme fatigue, stomach pain, difficulty swallowing, erectile dysfunction, and intermittent episodes of dark colored urine known as hemoglobinuria, all of which can impair quality of life. PNH patients are also at increased risk of developing blood clots, or thromboses, with 40% of PNH patients experiencing a thrombotic event during their lifetime.
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