Normocytic Anemias w/ CRC >3% Flashcards
There are 2 locations that you can kill a RBC, what are these?
Intravascularly
Extravascularly- spleenic macrophage
What clinical finding do you see in patients with extravascular hemolytic anemia?
Jaundice- increased unconjugated bilirubin
What clinical findings do you see in patients with intravascular hemolytic anemia?
Hemoglobinuria
Low haptoglobin levels
Hemolytic anemias can be caused by intrinsic or extrinsic factors. Detail the intrinsic causes of hemolytic anemia.
M- membrane defects
A- abnormal Hb
D- deficiency of enzymes
List hereditary causes of RBC membrane defects.
Hereditary spherocytosis
Paroxysmal nocturnal hemoglobinuria
What is the inheritance pattern of Sickle cell disease?
Autosomal recessive disorder
What are the 2 pathologic processes in sickle cell disease?
Hemolytic anemia
Painful vasoocclusive crises
What is the most common cause of death in children with sickle cell disease?
Strep. pneumoniae sepsis- increased susceptibility to infections due to autosplenectomy
Contrast Heinz bodies and Howell-Jolly bodies.
Heinz bodies: aggregates of denatured hemoglobin, removal by splenic macrophages produces bite cells
Howell-Jolly bodies: nuclear remnants within RBCs, indicate absence/hypofunction of spleen
Detail the inheritance of G6PD deficiency.
XR
What is the role of glutathione?
Neutralizes hydrogen peroxide to water
What effect does hydrogen peroxide have on Hb?
Damages Hb causing it to precipitate
Is G6PD deficiency primarily an intravascular or extravascular hemolytic anemia?
Intravascular- Heinz bodies damage RBC membranes
What precipitates hemolysis in a patient with G6PD deficiency?
Infection
Drugs
Regarding autoimmune hemolytic anemia, what type of antibody is associated with the “warm” and “cold” types?
Warm- IgG
Cold- IgM
What is the most common autoimmune hemolytic anemia, and what most commonly causes this condition?
Warm, due to lupus
Define immune hemolytic anemia.
Group of extrinsic hemolytic anemias with intravascular or extravascular hemolysis
What are the categories of immune hemolytic anemias?
Autoimmune
Drug induced
Alloimmune
What is the most common cause of immune hemolytic anemia?
Autoimmune
Detail the hemolysis that occurs in patients with IgG mediated hemolysis.
Extravascular- removed by splenic macrophages
Detail the hemolysis that occurs in patients with IgM mediated hemolysis.
Intravascular- activation of complement
If you suspect an autoimmune hemolytic anemia, what test must you order?
Coombs test
What does a direct/indirect Coombs test look for?
Direct- RBCs sensitized with IgG
Indirect- detects antibodies in the serum
The second most common cause of immune hemolytic anemia is drugs. There are 3 types of drug induced hemolytic anemia, what are these?
Type 2 hypersensitivity- IgG against drug, drug attached to RBC membrane (penicillin)
Type 2 hypersensitivity- (methyldopa( alters Rh antigens, then autoantibodies form against
Innocent bystander- IgM attaches to drug and forms immune complex, complex attaches to RBC (quinidine)
Define a schistocyte. What conditions are these commonly seen in?
Fragmented RBC
Commonly seen in micro/macro-angiopathic hemolytic anemias
A patient comes in complaining of red urine. On physical exam there is a systolic ejection murmur at the 2nd intercostal space of the right sternal border. They have a low MCV. What do you expect to see on the peripheral blood smear, why?
Schistocytes- likely due to aortic stenosis
