Topic 16-18: Anemia and non-neoplastic hematology Flashcards
Based on general pathogenesis, there are three types of anemias. what are they?
Hemolytic anemias, blood loss anemia, and anemia due to lack of erythropoiesis.
what are the 6 types of anemias due to decreased synthesis?
- Iron deficient
- megaloblastic
- pernicious
- aplastic
- anemia of chronic disease
- myelophthisic
what are the pathogenesis possibilities for iron deficient anemia?
- chronic blood loss
- low iron intake in diet
- increased demand (due to pregnancy, childhood growth)
- malabsorption (celiac, pancreatitis, gastrectomy)
what is the morphology of RBCs with iron deficiency anemia?
microcytic hypochromic anemia
megaloblastic anemia is caused by which deficiency?
folic acid and vit B12 - both are important for DNA synthesis
what are the 3 pathomechanisms at play in megaloblastic anemia?
- cell gigantism due to the slow replication of DNA but normal speed replication of RNA and protein leading to too many organelles and RNA with less DNA.
- also: defective DNA replication stops cell division thus the cell just keeps replicating the DNA –> 4n, 8n
- DNA defects cause apoptosis, thus less blood cells reach maturity –> low numbers of large blood cells
morphology of megaloblastic anemia?
- large megaloblastic (erythroid precursors), diffuse chromatin
- RBCs are hyperchromatic (but have normal hemoglobin levels!)
- giant metamyelocytes (granulocyte precursors)
- large megakaryocytes with bilobed nuclei
- hypersegmented neutrophils
which has worse consequences, folate or B12 deficiency?
B12
folate deficiency is normally due to what?
poor diet
what is another name for B12 def? what is the pathogenesis of B12 def?
pernicious anemia or cobalamin deficiency
- poor diet (strict vegans normally)
- lack of intrinsic factor due to autoimmune gastritis (anti-parietal cell rxn)
- gastrectomy or ileal resection
- crohn’s, whipple
what is one significant symptom of B12 def that isn’t seen in the blood?
demyelination of peripheral nerves and of posterior and lateral column
what is aplastic anemia?
suppression of multipotent stem cells leading to bone marrow failure (hypocellular marrow)
pathogenesis of aplastic anemia? 5
- most are idiopathic! (viral infections, etc)
- the remaining are due to myelotoxic agents such as radiation therapy, chloramphenicol, sulfonamides
- some viral infections
- autoreactive T cells
- genetic (defect in telomerase)
anemia of chronic disease is due to what?
suppression of erythropoiesis due to chronic inflammation with infectious disease, cancer, or immune disorders
pathogenesis of anemia of chronic disease?
- high levels of hepcidin
- inflam blocks EPO production
myelophthisic anemia is what?
bone marrow failure due to infiltration of the marrow by tumor metastasis (breast, lung, prostate)
morphology of myelophthisic anemia?
teardrop RBCs, misshapen,
thrombocytopenia
mild leukocytosis and precursors in peripheral blood
anemia of blood loss can be what two types?
hemolytic and hemorrhagic
what is the difference between acute and chronic hemorrhagic blood loss?
in acute you first develop hypovolemic shock and anemia only develops a few days later
in chronic, there is iron deficient anemia
hemolysis can be what general type?
Intrinsic- inheritied hemolytic disorders
extrinsic - aquired
intravascular - RBC stress or damage (toxins, turbulance,)
extravascular - tissue macrophages in spleen or liver remove damaged cells
intravascular hemolysis is associated with what symptoms?
hemoglobinemia,
hemoglobinuria
hemosiderinuria
ATN - due to casts
jaundice
low haptoglobin,
High LDH
extravascular hemolysis is associated with what symptoms?
NOT hemoglobinuria and hemoglobinemia!!!
low haptoglobin
jaundice, bile stones
high LDH