TAILIEUCHUNG - Chapter 101. Hemolytic Anemias and Anemia Due to Acute Blood Loss (Part 17)

Bone Marrow Failure—Relationship between PNH and AA It is not unusual that patients with firmly established PNH have a previous history of well-documented AA. On the other hand, sometimes a patient with PNH becomes less hemolytic and more pancytopenic and ultimately has the clinical picture of AA. Since AA is probably an organ-specific autoimmune disease in which T cells cause damage to hematopoietic stem cells, the same may be true of PNH, with the specific proviso that the damage spares PNH stem cells. Skewing of the T cell repertoire in patients with PNH supports this notion. In addition, in. | Chapter 101. Hemolytic Anemias and Anemia Due to Acute Blood Loss Part 17 Bone Marrow Failure Relationship between PNH and AA It is not unusual that patients with firmly established PNH have a previous history of well-documented AA. On the other hand sometimes a patient with PNH becomes less hemolytic and more pancytopenic and ultimately has the clinical picture of AA. Since AA is probably an organ-specific autoimmune disease in which T cells cause damage to hematopoietic stem cells the same may be true of PNH with the specific proviso that the damage spares PNH stem cells. Skewing of the T cell repertoire in patients with PNH supports this notion. In addition in mouse models PNH stem cells do not expand when the rest of the bone marrow is normal and by high-sensitivity flow cytometry technology very rare PNH cells harboring PIG-A mutations can be demonstrated in normal people. In view of these facts it seems that an element of bone marrow failure BMF in PNH is the rule rather than the exception. An extreme view is that PNH is a form of AA in which BMF is masked by the massive expansion of the PNH clone that populates the patient s bone marrow. The mechanism whereby PNH stem cells escape the damage suffered by non-PNH stem cells is not yet known. Paroxysmal Nocturnal Hemoglobinuria Treatment Unlike other acquired HAs PNH may be lifelong and most patients receive supportive treatment only including transfusion of filtered red cells2 whenever necessary. Folic acid supplements at least 3 mg d are mandatory the serum iron should be checked periodically and iron supplements administered as appropriate. Long-term glucocorticoids are not indicated because there is no evidence that they have any effect on chronic hemolysis and their side effects are considerable and potentially dangerous. The only form of treatment that can provide a cure for PNH is allogeneic bone marrow transplantation BMT when an HLA-identical sibling is available BMT should be offered to any young .

• Y học thường thức
• Hemolytic Anemias
• Anemia Due
• Acute Blood Loss
• tài liệu học ngành y
• Harrisons Internal Medicine
• bài giảng bệnh học
• Technical Aspects
• Vascular Diagnostics
• New Horizons
• Agent Properties
• medical books
• pharmacology
• epidemiologic
• Obstetrics
• anatomy
• Preventing Morbidity
• Multidisciplinary Care