RBC eval, Anemias due to blood loss, Hemolytic Anemias Flashcards
Main protein in a RBC, that transports oxygen and carbon dioxide
Hemoglobin
What is Hematocrit?
% of whole blood volume that is occupied by red cells
How do you calculate Mean Corpuscular Volume (MCV)?
Hematocrit/RBC
How do you calculate Mean Corpuscular Hemoglobin (MCH)?
Hgb/RBC
How do you calculate Mean Corpuscular Hemoglobin Concentration (MCHC)?
Hgb/Hematocrit
Microcytic Anemia has a ___ MCV
LOW
Macrocytic Anemia has a ____ MCV
HIGH
Hypochromic Anemia has a ____ MCH
LOW
Red Cell Distribution Width (RDW) measures?
The variability in size of RBCs in circulation
Anisocytosis
Increased RDW = Increased variability in size of RBCs
Reticulocytes are immature erythrocytes. What do they contain that RBCs do not?
RNA
What stain can show the RNA that remains in Reticulocytes?
Supravital stain - RNA appears polychromatic (purple-grey)
With Acute Blood loss, what will the MCV and MCH be?
Normal
With Acute Blood loss, there is initially a LOW reticulocyte count. How long will it take for there to be an increase in reticulocytes?
6-7 days after blood loss
With Acute Blood loss, the anemia will manifest through LOW ____ 6-12 hours later
Hemoglobin and Hematocrit
With Chronic Blood loss, how do you get anemia?
If the rate of loss exceeds the rate of replacement
How does Chronic Blood loss present?
Iron deficient Anemia
Hemolytic anemias involve?
Peripheral destruction of RBCs
What attempts to compensate for Hemolytic anemias?
Bone marrow
Hereditary spherocytosis
Mutations lead to unstable membrane skeletal proteins of the RBC
Mutations lead to unstable membrane skeletal proteins of the RBC
Hereditary Spherocytosis
RBCs with Hereditary Spherocytosis are ____ deformable
LESS
When the RBCs with Hereditary Spherocytosis travel through the spleen, what occurs?
They are quickly degraded
= splenomegaly/hypersplenism
What is the treatment for Hereditary Spherocytosis and its side effects?
Remove the spleen
- Increase in Howell - Jolly bodies
What are Howell-jolly bodies and when are they seen?
DNA inclusions in RBCs that are normally removed by the spleen
- They are seen in cases of Hereditary spherocytosis where the spleen has been removed, thus the bodies cannot be removed and they remain
3 symptoms of Hereditary spherocytosis?
Anemia
Splenomegaly
Jaundice
In conditions that over-rely on erythropoiesis (like hereditary spherocytosis), infection with what can cause an aplastic crisis (shut down of new RBCs)?
Parvovirus B19 - destroys erythroid precursors
How is G6PD deficiency inherited?
X-linked recessive
Under oxidative stress, how are normal cells protected?
- G6PD creates NADPH
- NADPH helps create Reduced Glutathione
- Reduced Glutathione can peroxidase free radicals and get rid of them
Under oxidative stress, those with G6PD will see what symptoms?
Episodic hemolysis of RBCs a few days after exposure
What are Heinz bodies?
Denaturation of proteins in RBCs caused by oxidative damage
How are Heinz bodies removed and the remaining bite cells are seen with?
The spleen “bites” the heinz bodies to remove them
= bite cells are seen with G6PD deficiency
Sickle Cell Anemia involves a mutation in the ____ chain = HgbS
beta chain
- glutamic acid –> valine
Sickle cell trait
Heterozygous for HgbS
Sickle cell disease
Homozygous for HgbS
Populations with increased incidence of HgbS will have more?
Variants of Hgb
With Sickle cell disease, RBCs polymerize and lengthen. What can cause this?
Hypoxia
Sluggish blood flow and low pH
Intracellular dehydration
Sickled cells can undergo hemolysis and vaso-occlude blood flow = hypoxia (induce polymerization). Damage to the sickled cell membrane causes?
Increased adhesion - vaso-occlusion
Treatment for Sickle cell Anemia?
Hydroxyurea (increased Hgb Fetal)
Supportive care
CRISPR
What is a more mild version than Sickle cell (homozygous for SS Hgb)?
SC disease
SC Disease involves Hgb C, what can it do?
Hgb C can crystallize but NOT polymerize
What cells will you see with SC disease?
Target cells (poikilocytes) = abnormal shape
How many genes are there for beta-globin?
2
How many genes are there for alpha-globin?
4
1 mutation in beta-globin
Beta-thalassemia trait or minor
Symptoms of beta-thalassemia minor
Mild, microcytic anemia
2 mutations in beta-globin
Beta-thalassemia major
Symptoms of beta-thalassemia major
Severe anemia
Extramedullary hematopoiesis
Marrow expansion = crew cut appearance
Switch to Hgb Fetal
Severe anemia, extramedullary hematopoiesis, crew cut marrow expansion could indicate?
Beta-thalassemia major
3 alpha-globin genes hit
Hb H disease
Hb H disease has a tetramer of beta-globin. This has a ____ oxygen affinity which means?
HIGH affinity = poor oxygenator
Symptoms of Hb H disease?
Anemia and splenomegaly
Paroxysmal Nocturnal Hemoglobinuria involves what mutations?
PIGA on the x chromosome - affect Hematopoietic stem cells
PIGA mutations with Paroxysmal Nocturnal Hemoglobinuria cause lack of?
CD55 and CD59 that bind complement
Lack of CD55 and CD59 with Paroxysmal Nocturnal Hemoglobinuria causes?
MAC to lyse RBCs at night = blood in urine and thrombosis
Symptoms of Paroxysmal Nocturnal Hemoglobinuria?
Blood in the urine at night and thrombosis
Those with PNH are at risk for?
AML/MDS
What drug can treat PNH by turning off the complement?
Eculizamab (blocks C5 -> C5a)
Those being treated for PNH with Eculizamab are at risk for infections with?
Neisseria species
Warm hemolytic anemia involves what Ig binding and where are the cells phagocytosed?
IgG
- phagocytosed in the spleen
Cold hemolytic anemia involves what Ig binding and where/why are the cells phagocytosed where they are?
IgM
- c3b deposits and cells are phagocytosed in the spleen, bone marrow, liver
Symptoms of cold hemolytic anemia?
Similar to Raynauds - nose and finger manifestations
What is an example of red cell trauma that causes hemolysis?
Mechanical shear of the cells by a prosthetic heart valve
