Anemia/Red Cells Flashcards
When do you see target cells?
when there is increased surface/volume ratio (thalassemia, hemoglobinopathies, liver disease, post splenectomy / hyposplenism, severe iron deficiency, LCAT deficiency)
When do you see spherocytes?
Decreased surface/volume ratio (> MCHC)
AIHA, HS, G6PD, MAHA, hypersplenism, burns, PK deficiency
Acanthocytes vs echinocytes?
Acanthocytes – 5-10 spicules of varying length, irregular, seen in liver disease, DIC, hyposplenism, hypothyroid
Echinocytes – 10-30 spicules of equal length, equally distributed over RBC. Can be artifact, dehydration, liver disease, PK deficiency, after a RBC transfusion
how do you calculate the reticulocyte index?
Reticulocyte count x patient’s hematocrit/normal hematocrit
how do you diagnose maternal-fetal hemorrhage
Kleihauer-Betke (acid elution detection of hemoglobin F)
where is folate absorbed
duodenum
where is vit b12 absorbed
terminal ileum
which proteins are important for vertical linkage through the RBC membrane?
spectrin
ankyrin
protein 4.2
band 3
HS is an issue with what?
vertical linkage proteins in the RBC membrane
what is the pathophysiology of hereditary elliptocytosis?
issues with the horizontal linkage proteins in RBC membrane
what is pathophysiology of stomatocytosis?
issue with ion transport
stomatocyte = small mouth cells
what causes Gilbert’s syndrome
mutation in UGT1A1 gene causing deficiency UGT-1A enzyme
what are the variants of G6PD deficiency?
Class I: chronic hemolysis - severe G6PD deficiency
Class II: Intermittent hemolysis despite severe deficiency
Class III: Intermediate hemolysis due to moderate deficiency (usually due to drugs/infections)
Class IV: normal G6PD, no hemolysis
inheritance of HS?
autosomal dominant (75% of cases)
most common protein mutated in HS?
ankyrin (50-67% of HS)
what are heinz bodies and in what conditions do you see them?
Denatured aggregates of hemoglobin
- Newborn
- Thalassemia
- G6PD
- Chronic liver disease
- Asplenia
what are howell-jolly bodies and in what conditions do you see them?
Nuclear remnant inclusions
- Newborn
- Asplenia
what is basophilic stippling and what conditions do you see it in?
Aggregates of ribosomal RNA
- Lead poisoning
- Iron-deficiency
- Hemolytic anemias (thal trait)
how much folic acid should a person with a chronic hemolytic disorder be taking?
1mg/day
definition of iron deficiency
ferritin < 15 mcg/L
what transporter takes up iron on the intestinal side of the endothelium?
DMT1
what transporter regulates movement of iron out of the endothelium into the circulation?
ferroportin
what protein blocks ferroportin?
hepcidin
what is poikilocytosis?
variation in cell shapes, abnormal RBCs > 10% of the population
what is anisocytosis?
variation is RBC size
warm aiha - describe
IgG antibodies, maximally reactive at 37 C
causes extravascular hemolysis via spleen (RES)
smear: spherocytes
cold aiha - describe
IgM antibodies, maximally reactive at 0-5 C
causes intravascular hemolysis via complement, extravascular via RES
paroxysmal cold hemoglobinuria - describe
IgG antibodies reactive at cold temps, causes complement mediated hemolysis (donath-landsteiner)
PNH - lack of what cell surface proteins
CD55 and CD59
PNH - what gene
PIG-A
cold agglutinins are associated with what infection?
mycoplasma
donath landsteiner antibody is usually specific to what?
p-antigen
