Normochromic Anemias Flashcards
Hereditary Spherocytosis
Common among Northern Europeans (1:5000)
Represented by a deficiency in membrane proteins Spectrin and Ankyrin
Protein band 3 and Protein band 4.2
Osmotic fragility test
confirming test for Hereditary Spherocytosis. Normal RBCs initially hemolyze at 0.45% NaCl. Hereditary Spherocytosis patients are less able to tolerate an influx of water. Lyse occurs at 0.65% NaCl
Hereditary Stomatocytosis identified on a smear when:
10-30% stomatocytes are present in the smear. RBCs will appear as if the cells are smiling
Hereditary Elliptocytosis
The red cell membrane has a defective or deficient spectrin
The four clinical subtypes of Hereditary Elliptocytosis are:
Common hereditary elliptocytosis
Southeast asian ovalocytosis
spherocytic hereditary elliptocytosis
hereditary pyropoikilocytosis
Common hereditary elliptocytosis
mild common: cells are present in 30-100% of patients. no symptoms
severe common: seen more often in infants but as patient ages, it converts to mild
Southeast asian ovalocytosis
Band 3 defect
Spherocytic hereditary elliptocytosis
spherocytes and elliptocytes are present
hereditary pyropoikilocytosis
red cell budding, rare elliptocytes and spherocytes in circulation
cell fragments are at temperatures lower than normal. causes poor growth and facial deformities
Pyruvate kinase deficiency
red blood cells lacking this enzyme are unable to generate ATP from ADP for membrane function.
Glucose-6-Phosphate Dehydrogenase
key part of phosphogluconate pathway.
keeps glutathione in reduced state to help prevent oxidative stress. Oxidative stress leads to hemolysis
Favism
occurs within hours of contact of gaga beans either through residue or ingestion.
Diagnosis of G6PD
timing of test is critical. testing should NOT be done during hemolytic episode
