11. Hemolytic and Intrinsic Anemia Flashcards
1
Q
*** Classification of Hemolytic Anemias
A
Intrinsic Defects -
Extrinsic Defects- Outside the body “attacks” the cells
2
Q
Hemolytic Anemia
A
-RBCs have a shortened life span and hemolyze before 120 days.
3
Q
Extravascular Hemolysis
A
- break down of red blood cells outside of the blood vessels
4
Q
Intravascular Hemolysis
A
- break down of red blood cells inside the blood vessels
- doesn’t happen too often
5
Q
**Increased extravascular hemolysis
A
Liver becomes overwhelmed with the amount of billirubin…
6
Q
*** Increased intravascular hemolysis
A
look up in book :(
7
Q
Tests Reflecting Increased RBC destruction
A
Intravascular
- Hemoglobinuria, hemoglobinemia, hemosiderinuria
- Decreased haptoglobin
- Increased LDH
- Increased serum bilirubin
- Increased retics
8
Q
Pyruvate Kinase Deficiency
A
- most common enzyme deficiency in the Embden-meyerhof pathway
- autosomal recessive
- results in decreased ability to generate ATP
- Affects ability to maintain osmotic gradient
- Results in accumulation of 2,3-DPG (decreases the affinity for oxygen to bind to hemoglobin)
- Clinical - variable anemia, chronic hemolysis, splenomegaly, gallstones
9
Q
Pyruvate Kinase Deficiency - Lab Values
A
- Normocytic, normochromic anemia
- increased Reticulocytes (even more post-splenectomy)
- Smear - increased polychromasia, anisocytosis, nRBC
- Increased bilirubin, decreased haptoglobin
- Diagnostic test - PK screen, PK assay (flourescent spot test)
10
Q
Heinz bodies / Bite cells
A
- denatured hemoglobin in RBCs
- results from oxidation
- cells containing theses are destroyed by the spleen
11
Q
G6PD Deficiency
A
- X-linked recessive
- inability to protect against oxidative stress
- Clinically asymptomatic until oxidative stress
- During hemolytic episodes, may experience hemoglobinuria and jaundice
- There are variants of G6PD ( Type A -/+ Type B -/+)
12
Q
G6PD Laboratory Values
A
- Normocytic, normochromic anemia
- Smear - Increased poly, poik, bite or helmet cells** (halmark)
- Increased bilirubin, decreased haptoglobin
- Heinz body prep - stain with supravital stain, not specific for G6PD
- Diagnostic test - G6PD screen or assay (fluoresce if present)
13
Q
RBC Membrane
A
- Semi-permeable lipid bi-layer supported by a protein cytoskeleton
- Chemically - 40% lipid, 52% protein, 8% carbohydrate
- Glycophorin: principal RBC glycoprotein, location of RBC antigens
- Spectrin: major cytoskeletal protein (along with ankyrin)
14
Q
Hereditary Spherocytosis
A
- autosomal dominant but can be from a new mutation
- Membrane defect resulting in loss of surface area of RBC membrane
- Spectrin, ankyrin deficiency
- Cells demonstrate increased osmotic fragility
- Clinical - anemia, jaundice, splenomegaly
- Frequent gallstones due to increased bilirubin in bile
- Treatment - splenectomy
15
Q
Hereditary Spherocytosis Laboratory Values
A
- Increased MCHC (no central palor)
- Smear - spherocytes, increased poly
- Increased reticulocytes
- Abnormal osmotic fragility test
- RBC membrane studies
