Treating immune-mediated<unk>  involves suppression of the immune system, an effect achieved by daily medicine or, in more severe cases, a bone marrow transplant, a potential cure. The transplanted bone marrow replaces the failing bone marrow cells with new ones from a matching donor. The multipotent stem cells in the bone marrow reconstitute all three blood cell lines, giving the patient a new immune system, red blood cells, and platelets. However, besides the risk of graft failure, there is also a risk that the newly created white blood cells may attack the rest of the body ("graft-versus-host disease"). In young patients with an HLA-matched sibling donor, bone marrow transplant can be considered as a first-line treatment. Patients lacking a matched sibling donor typically pursue immunosuppression as a first-line treatment, and matched, unrelated donor transplants are considered second-line therapy. Treatment often includes a course of antithymocyte globulin (ATG) and several months of treatment with ciclosporin to modulate the immune system. Chemotherapy with agents such as cyclophosphamide may also be effective but is more toxic than ATG. Antibody therapy such as ATG targets T cells, which are believed to attack the bone marrow. Corticosteroids are generally ineffective, though they are used to ameliorate serum sickness caused by ATG. Normally, success is judged by bone marrow biopsy six months after initial treatment with ATG. One prospective study involving cyclophosphamide was terminated early due to a high incidence of mortality from severe infections as a result of prolonged neutropenia. Before the above treatments became available, patients with low leukocyte counts were often confined to a sterile room or bubble (to reduce risk of infection), as in the case of Ted DeVita. Follow-up Full blood counts are required on a regular basis to determine whether the patient is still in remission. Many patients with<unk>  also have clones of cells characteristic of paroxysmal nocturnal hemoglobinuria (PNH), a rare disease that causes anemia with thrombocytopenia and/or thrombosis and is sometimes referred to as<unk> /PNH. Occasionally PNH dominates over time, with the major manifestation of intravascular hemolysis. The overlap of<unk>  and PNH has been speculated to be an escape mechanism by the bone marrow against destruction by the immune system. Flow cytometry testing is performed regularly in people with previous<unk>  to monitor for the development of PNH.
Aplastic anemia
Acute lymphoblastic leukemia
Refractory anemia with excess of blasts
Polycythemia vera
Myelodysplastic syndrome
Myomatous erythrocytosis syndrome
Essential thrombocythemia
Refractory cytopenia of childhood