Graft versus host disease (GVHD) is a common complication of bone marrow/stem cell transplantation. It is caused when the donor's immune cells (the "graft"), now in the patient, react to the patient's body (the "host") as if it was foreign.
PNH can strike people of any age, race or gender. Only about 500 people are diagnosed with PNH in the U.S. each year. PNH tends to be more common in adults in their thirties and early forties.
Between 600 and 900 people are diagnosed with