Chapter 14-RBCs And Bleeding Disorders Flashcards
What is the major difference regarding the spleen between intravascular and extravascular hemolysis
Splenomegaly is not seen in intravascular hemolysis
What is the antibody present in cold hemolysin antibodies
IgG
In addition to a mutation in the Beta chain, which event in the alpha chain further worsens the prognosis
Gaining an Alpha chain chromosome, leading to further imbalance and alpha chain deposition
How does acute blood loss affect white cells
- massive decreased in blood pressure results in increased levels of adrenergic hormones
- mobilizes granulocytes and Increased leukocytosis
Which type of Von Willebrand disease is quantitative
Type 1 and 3
What is the significance of HgH
Such a high affinity for Oxygen that it can be let go and used normally
What are the histological appearances during megablastic anemia
- macrocyclic and oval that lack the central pallor of normal RBCs and appear hyperchromic, but no rise in MCHC
- Low reticulocyte count
- Neutrophils show nuclear hypersegmentation 6 lobules
What is the pathogenesis of hemolytic uremic syndrome (HUS)
- Infection with E Coli O157:H7 which contains the Shiga like toxin
- Creates endothelial defects that cause the accumulation of platelets
What is the mechanism that HIV induced thrombocytopenia
Megakaryocytes possess the receptors CD4 and CXCR4, which allows for infection
-Furthermore, can cause B cell hyperplasia and lead to production of alloantibodies to the platelets
What are the numbers and locations of the hemoglobin components
- 2 alphas from an identical pair on chromosome 16
- 2 betas on a single gene on chromosome 11
What is Kasabach-Merritt syndrome
associated with DIC:
-giant hematomas as a result of thrombi forming within the neoplasm because of stasis and recurrent trauma to the blood vessels
Which form of hemolysis is seen in G6PD deficiency
Extravascular and intravascular hemolysis
What is the method of pathogenesis is cold antibody anemia
Temperature falls, IgM binds to RBCs and fixes complement, C3b deposits, temperature warms up and allowed to flood, the C3b binds to phagocytes and is removed
What are the lab test values seen in thrombotic microangiopathies
Aka TTP and HUS
-PT and PTT are normal
What is the amino acid substitution in the cause of HbC
Lysine for glutamate
What is the mechanisms of disease in the case of atypical hemolytic uremic syndome (HUS)
Defects in complement protein H, CD46, or factor I
*All inhibit the activation of the alternative pathways
What is the role of OCs in avitaminatosis
-Decreased absorption
Following blood loss, how long does it take for the CFU-Es to mature and appear as newly released RBCs (reticulocytes) in the Peripheral blood
5 days
What is the treatment for hereditary spherocytosis
Splenectomy, which solves the problem of anemia as they are not removed by macrophages
In those patients with hereditary spherocytosis (HS) what is the underlying cause of an aplastic crisis
Infection of the parvovirus, which infects and kills the progenitors in the bone marrow
What is the cause of chronic immune thrombocytopenia purpura (ITP)
Autoantibody destruction of platlets
What are the characteristics clinical findings in hemophilia A
- Easy bruising
- Massive Bleeding felling procedures
- spontaneous hemorrhages in trauma locations
*Patechiae are absent
What is occuring during myelophthisic anemia
There is morrow failure as a result of displacement by a space occupying lesion
What are the secondary clinical features seen in Beta thalassemia major
- Splenomegaly (extramedulary site)
- cardiac disease usually cause of death (hemochromatosis)