ANEMIA CAUSED BY INCREASE DESTRUCTION OF RBCS Flashcards
(48 cards)
- Commonly inherited as an autosomal dominant trait
- Defects in proteins that disrupt the vertical interactions between transmembrane proteins and the underlying protein cytoskeleton.
Hereditary Spherocytosis
Hereditary Spherocytosis:
Loss of ______ attached to RBC cytoskeleton
_____surface area-to-volume ratio
lipid membrane
Decrease
Hereditary Spherocytosis:
3 Clinical Manifestations:
- Anemia
- Jaundice
- Splenomegaly
Hereditary Spherocytosis distinguished from immune-related hemolytic anemia thru _____
DAT
Hereditary Spherocytosis:
Lab Findings:
- Uniform ____ on PBS
- MCHC _____
- ___ Osmotic Fragility Test (OFT)
Spherocytes
High (>36%)
Increase result in Osmotic Fragility Test (OFT)
Hereditary Spherocytosis:
Hemolysis at ___
> 0.45% NaCl
Traditional test method for H.S
Osmotic Fragility Test (OFT)
Hereditary Spherocytosis:
Specimen:
Heparinized blood
Hereditary Spherocytosis:
Reagent:
Different concentrations of NaCl Solutions (0.85% to 0%)
Hereditary Spherocytosis:
OFT Normal Results:
Initial hemolysis at ____
Complete hemolysis at ____
0.45% NaCl
0.35% NaCl
Hereditary Spherocytosis:
Incubating the blood at 37C for ____ before performing the test (Incubated OFT) allows HS cells to become more ___ and is often needed to detect mild cases
25 hours
spherical
Has been proposed as a more sensitive alternative for confirmation of H.S.
Eosin-5’ – maleimide binding test (EMA)
Eosin-5’ – maleimide binding test (EMA)
PRINCIPLE:
Flow Cytometry
Eosin-5’ – maleimide binding test (EMA):
EMA results with H.S
Lower
Gene mutation that disrupts horizontal RBC cytoskeleton
Hereditary Elliptocytosis
Elliptocytosis can also be seen in patients with the Leach phenotype who lack ______
Gerbich antigens
___ is the null/absent phenotype under the Gerbich Blood group system
Leach phenotype
Majority of patients with HE are ________, and only about __% have moderate to severe anemia
asymptomatic
10
RBCs show some degree of a low thermal stability (fragments at 45C)
Hereditary Pyropoikilocytosis
Hereditary Elliptocytosis:
Observed in individuals who lack _______ on their RBC membrane
Glycophorin C
Condition caused by a mutation in the gene for band 3
= increased rigidity of the membrane and resistance to invasion by malaria.
Hereditary Ovalocytosis / Southeast Asian Ovalocytosis
Hereditary Ovalocytosis / Southeast Asian Ovalocytosis:
Condition caused by a mutation in the gene for ____ that results in increased rigidity of the membrane and resistance to invasion by ____
band 3
malaria
Hereditary Stomatocytosis:
Major categories:
Defect in membrane cation permeability (Na, K), resulting in a net increase in the intracellular cation concentration. More water enters the
cell causing swelling.
Overhydrated HS (Hereditary hydrocytosis)
Hereditary Stomatocytosis:
Major categories:
- Most common form of stomatocytosis
- Defect in membrane cation permeability, resulting in a reduced intracellular cation concentration.
- Water is lost from the cell.
Dehydrated HS (Hereditary xerocytosis)
