B3.035 - Hemolytic Anemias Prework 1 Flashcards
What does intrinsic hemolytic anemia mean
defect in RBC itself
What does extrinsic hemolytic anemia mean
defect/problem outside RBC but affects RBC
What does intravascular hemolytic anemia mean
RBC breakdown with massive release of free Hgb in circulation
What does extravascular hemolytic anemia mean
RBC breakdown in reticuloendothelial system cells (macrophages in spleen and liver) with capture of Hgb
What is extravascular hemolytic anemia usually caused by and does any Hgb get into circulation?
Decreased deformability of cell and yes
what causes reticulocytosis
anemia decreases RBC mass which stimulates kidney to release erythropoetin which stimulates bone marrow to increase amount of reticulocytes
In EH what are the reticulocyte count, EPO, polychromasia labs going to show
increased
In EH what happens to LDH
increased
In EH unconjugated bilirubin is
increased
In EH haptoglobin is
Decreased or normal
In EH serum free hemoglobin is
Absent
In EH urine hemoglobin is
Absent
In IH reticulocyte count, EPO, polychromasia is
increased
In IH LDH is
Increased
In IH unconjugated Hgb is
Increased
In IH haptogobin is
decreased
In IH serum free Hgb is
present
In IH urine Hgb is
present
What diseases have intrinsic etiology
Hemoglobinopathy - sickle cell
Thalassemia (microcytic) - alpha and beta
Membrane abnormality - heredetrary spherocytosis
RBC enzyme defects - G6P dehydrogenase deficiency
Paroxysmal nocturnal hemoglobinuria
What diseases have extrinsic etiology
Autoimmune hemolytic anemia
Traumatic hemolytic anemia
infections like malaria
when looking for hemolytic anemia what lap features would you look for
Reticulocytosis
anemia
blood smear morphology
Intravascular vs extravascular
Most hemolytic anemias are what -cytic
normocytic
what is the exception to the rule that hemolytic anemias are normocytic and what type is it
Thalassemias is microcytic and hypochromic
what disease is characterized by sphistocytes
microangiopathic hemolytiv anemia
what disease is characterized by sperocytes
hereditary spherocytosis, warm autoimmune hemolytic anemia
what disease is characterized by RBC agglutination
cold autoimmune hemolytic anemia
what are spherocytes
when pieces of RBC membrane get taken up by splenic macrophages, RBC goes from biconcave shape to sphere
what is hemoglobinopathy (eg. sickle cell)
structurally abnormal hemoglobin due to mutation in alpha or beta globin gene
Extravascular, intrinsic, inherited
what is thalassemia
Decreased production of alpha or beta chains due to mutations
Extravascular, intrinsic, inherited
what are important proteins of the cytoskeleton of RBCs
Ankyrin, spectrin, band 3, band 4.2
what is spherocytosis
membrane defect in cytoskeletal protein
Extravascular, intrinsic, inherited
what is an RBC enzyme defect
G6P dehydrogenase deficiency
what is G6P dehydrogenase deficiency
decreased level of critical enzyme, increased sensitivity to oxidative stress
Intravascular and extravascular intrinsic inherited XR
what is the inhertiance pattern of hereditary spherocytosis
Ankyrin is the culprit usually and AD
what is G6PD used for
reducing GSH
what is PNH
clonal disorder with mutation in phosphatidylinositol glycan complementation group A (PIGA) gene
what does PIGA do
its an anchor protein that works to prevent complement mediated lysis of RBCs
what proteins help anchor RBCs to PIGA
CD55, CD59
describe PNH (intra/extra, intrinsic/extrinsic, aquired/hereditary)
Intravascular intrinsic aquired
patients with PNH are at risk of what
blood organ cancers
what are the autoimmune hemolytic anemias
Warm autoimmune hemolytic anemia
Cold autoimmune hemolytic anemia
what is warm AHA
IgG antibodies active at 37 degrees recognized by splenic macrophages (Fc receptors) with membarne loss (Spherocytes) extravascular extrinsic aquired
what is cold AHA
IgM antibodies active below 37 degrees, large pentameric molecule can bind to more than 1 RBC (agglutination)and activate complement with complement mediated RBC lysis
intravascular and extravascular extrinsic aquired
how do you detect antibodies coating RBCs
coombs test
how do you treat cold AHA?
keep them warm!
what is direct coombs test
detects Abs coating RBCs
What is indirect coombs test
detects Ab in plasma that can react with RBCs
what is DAT
identifies IgG or IgM Abs coating RBCs, can differentiate etiology of spherocytes
what are allimunization and transfusion reaction for
ABO antibodies, is what happens when you transfuse a blood type other than your own would cause massive intravascular hemolysis
alloantibodies to other RBC antigens cause what
IgG, extravascular hemolysis over weeks
What is traumatic hemolytic anemia caused by
trauma in large vessels/heart (macroangiopathic)
intravascular extrinsic aquired
trauma in microcirculation
describe trauma in microcirculation
trauma due to widespread clots in microcirculation
Platelet thrombi - TTP, HUS
Platelet fibrin thrombi - DIC
what are found in trauma in microcirculation
schistocytes thrombocytopenia cariable abnormalities of coagulation tests
intravascular extrinsic aquired
