Secrets: Anemias
Terms
undefined, object
copy deck
- What are reticulocytes?
-
immature RBCs newly produced by bone marrow and released into blood
total # indicates effectiveness of RBC production - What can reticulocytes tell you about anemias?
-
anemia with high retic count means it's likely hemolytic anemia
low retic count means inadequate marrow production (ineffective erythropoeisis) - What are the microcytic anemias? How are they linked?
-
- iron deficiency anemia
- anemia of chronic disease
- alpha thalassemia
- beta thalassemia
- lead poisoning
all have a defect in hemoglobin synthesis - How does lead poisoning affect hemoglobin synthesis?
- inhibits 2 key enzymes in heme synthesis: alanine dehyrdratase and ferrochelatase
- Name 2 macrocytic anemias.
- vitamin B12 deficiency and folate deficiency
- Give examples of intravascular hemolysis.
-
RBC's are lysed within blood vessels
- complement in paroxysmal nocturnal hemoglobinuria
- mechanical prosthetic valves
- microangiopathic hemolytic anemias causing mechanical fragmentation of RBCs (like DIC)
- thrombotic thrombocytic purpura - Give examples of extravascular hemolysis.
-
splenic macrophages or Kuppfer cells in the liver destroy RBCs
(eg. hereditary spherocytosis, hypersplenism) - What happens to the hemoglobin in extravascular hemolysis?
-
hemoglobin in phagocytosed RBC is metabolized to bilirubin in the cell, reducing amount of hemoglobin in the blood or urine
(hemoglobinemia and hemoglobinuria) - What is haptoglobin?
- serum protein that binds free hemoglobin; binds much more hemoglobin in intravasuclar hemolysis
- Is there jaundice in extravascular hemolysis?
- yes
- What is usual cause of anemia in end stage renal failure? What is DOC?
-
lowered EPO production
also: uremia from renal failure can make the bone marrow less responsive to EPO
exogenously administered EPO - p. 152
- start with case 1