Bone Marrow Failure Flashcards
What is bone marrow failure?
The failure of bone marrow to produce bone cells leading to pancytopenia. Leads to low red cells white cells and plateletts.
What are the symptoms of anemia?
difficulty breathing, chest pain, fatigue
Leukopenia symptoms
mpouth sores, infection, fever
WHat are the causes of hypocellular bone marrow?
Aplastic Anemia as a reslut of Fancon’s anemia (inherited) or other aquired syndromes such as myelodisplastic syndromes
What is aplastic anemia
failure to produce RBCs, WBCs, plateletts
Fanconi’s anemia
becomes symptomatic at age 5. associated with bone marrow hypoplasia
Other causes of aplastic anemia?
ionizing radiation, chemical agents, infections, pregnancy,PNH (RBC and WBC susceptible to complement lysis)
Primary defect of aplastic anemia?
Absence of hematopoietic stem cells
Hallmarks of aplastic anemia
Decreased retic count, hypocellular marrow, pancytopenia
What is pure red cell aplasia
Characterized by a selective decrease in erythroid precursor cells. WBCs and plateletts unaffected
How do you get a red cell aplasia?
Viral or bacterial infection, patients with hemolytic anemia may suddenly stop erythropoiesis, patients with thymoma- t cell mediated attack of erythroblasts or EPO
WHat is a myelodysplastic syndrome?
primary, neoplastic stem cell disorder that tends to terminate in acute leukemia
What does the bone marrow look like in a myelodysplastic syndrome>
Normocellular or hypercellular with evidence of qualitative abnormalities like ringed sideroblasts.
What differntiates MDS from aplastic anemia?
Presence of a neoplastic clone
Can MDS lead to acute leukemia?
Yup…if the percentage of bone marrow blasts rises to over 20% then it is acute leukemia.
What is the method of mobilizing hematopoietic stem cells out of the bone marrow and into the peripheral blood for more easy access?
Apheresis
What are the three HSC characteristics that make it possible to transplant them?
Their ability to regenerate in the marrow, their ability to find their way back to the marrow following to IV infusion, their ability to be frozen with no damage.
What is autologous stem cell transplant?
take the stem cells out of a patient before hardcore chemo, reinfuse them later. Used mostly in the treatment of ppl with lymphoma and myeloma where intense chemo is needed.
Allogenic SCT?
Comes from someone else
How many HLA loci must match up to prevent graft vs host disease?
Three
Advantage of allogenic transplant?
When the pt has a leukemia or lymphoma the graft vs. host disease effect can help prevent relapse of the tumor.
Myeloablative therapy?
Chemo or irradiation of bone marrow prior to transplant.
WHat drugs are used in myeloablative therapy?
cyclophosphamide and busulfan
Why do myeloablative therapy>
has an immunosuppresive effect which prevents the transplant from being attacked by recipients immune system
