Patients who underwent an autologous or peripheral blood stem cell transplant may have available frozen stem cells that were not used during the initial transplant. Myelodysplasia Occasionally, patients who undergo an autologous BMT or peripheral blood stem cell transplant develop a condition called myelodysplasia. In patients with myelodysplasia, the blood-producing stem cell is damaged, usually by prior chemotherapy, and cannot produce a sufficient supply of blood cells. This condition, seen in less than 10 percent of patients, usually occurs 30 to 45 months after transplantation. Some patients whoan allogeneic BMT in an attempt to cure the condition.
Viral infections can interfere with blood cell production.
Cytomegalo-virus can reduce platelet production, and has been reported to cause low red blood cell and white blood cell counts in transplant patients as well. Human herpes virus 6 and Parvo virus B19 can also interfere with blood cell production. Drugs Certain drugs can suppress blood cell formation. Ganciclovir, a drug used to treat cytomegalovirus, is a good example. Sometimes stem cells produce sufficient blood cells, but the cells are subsequently destroyed.