Acquired RBC membrane abnormalities Flashcards
Caused by an acquired clonal hematopoietic stem cell mutation that results in circulating blood cells that lack CD55 and CD59
Paroxysmal Nocturnal Hemoglobinuria
the absence of CD55 and CD59 on the surface of the RBCs renders them susceptible to spontaneous lysis by complement
Paroxysmal Nocturnal Hemoglobinuria
Mutation in the PIGA gene
Paroxysmal Nocturnal Hemoglobinuria
Paroxysmal Nocturnal Hemoglobinuria test
Sugar water test
Principle is added to provide a medium of low ionic strength that promotes the binding of complement to the red cells
Sugar water test
Result in the laboratory diagnosis for Paroxysmal Nocturnal Hemoglobinuria
<5% hemolysis - negative
6%-10% hemolysis - borderline
>10% - positive
If positive of sugar water test, it is to be confirmed with ____
Sucrose hemolysis test/Ham test
Principle: Complement is activated by the alternative pathway, binds to red cells, and lyse the abnormal PNH cells
Acidified serum test/Ham test
Is the most common RBC enzyme defect
G6PD Deficiency
Confers protection against life-threatening P. falciparum and P. vivax
G6PD Deficiency
One of the important intracellular enzymes needed to protect hemoglobin and other cellular proteins and lipids from oxidative denaturation
G6PD
Catalyzes the first step in a series of reactions that detoxify hydrogen peroxide formed from oxygen radicals
G6PD
Laboratory diagnosis for G6PD Deficiency
Ascorbate cyanide screening test
Detects deficiencies in the pentose phosphate pathway
Ascorbate cyanide screening test
The most common form of hereditary nonspherocytic hemolytic anemia
Pyruvate Kinase Deficiency