Erythrocytes and the Erythrogram

Question 1

quantitative measures

Answer 1

parameters related to red cell mass
red cell indices

Question 2

parameters related to red cell mass

Answer 2

RBC count
Hgb concentration
HCT
PCV

Question 3

red cell indices

Answer 3

MCV
MCH
MCHC
RDW

Question 4

qualitative measures

Answer 4

poikilocytosis
chromasia
anisocytosis
agglutination
hemoparasites

Question 5

directly measured calculations

Answer 5

PCV
Hgb concentration
RBC count

Question 6

calculated parameters

Answer 6

MCV
MCH
MCHC
HCT
RDW

Question 7

Packed Cell Volume (PCV)

Answer 7

% of whole blood composed of RBC
decrease = anemia
increase = polycythemia, dehydration

Question 8

Hematocrit (HCT)

Answer 8

%
instrument determined calculated value comparable to PCV
affected by agglutination or RBC counts

Question 9

RBC counts

Answer 9

manual or automated
not influenced by WBC counts

Question 10

Hemoglobin (Hgb)

Answer 10

functional unit of RBC
heme has iron
globin has paired amino acid chains
synthesis during RBC maturation
assessed by lysing whole blood

Question 11

Mean Cell Volume (MCV)

Answer 11

measures average size of RBC
femtoliters (fL)
volume of each counted RBC, then mean is calculated

Question 12

normocytic

Answer 12

MCV within normal range

Question 13

microcytic

Answer 13

MCV below reference range

Question 14

microcytic causes

Answer 14

iron deficiency
dyserythropoiesis
liver shunts

Question 15

macrocytic

Answer 15

MCV above reference range

Question 16

macrocytic causes

Answer 16

increase in marrow erythropoiesis
dyserythropoiesis
artifact

Question 17

Mean Cell Hemoglobin (MCH)

Answer 17

picrograms (pg)
mean weight of Hb in average RBC

Question 18

Mean Cell Hemoglobin Concentration (MCHC)

Answer 18

g/dL
concentration of hemoglobin in average RBC
more accurate than MCH
roughly same for all species (33 g/dL)

Question 19

normochromic

Answer 19

MCHC within reference range
most non-regenerative anemias

Question 20

hypochromic

Answer 20

MCHC below reference range
regenerative anemias
iron depletion

Question 21

hyperchromic

Answer 21

does not exist
is artifact

Question 22

Red Cell Distribution Width (RDW)

Answer 22

%
index of variation in cell volume
high = varying more than normal
low = no clinical relevance

Question 23

anisocytosis

Answer 23

variation in cell size
macrocytes
microcytes
both

Question 24

chromasias

Answer 24

variation in cell color

Question 25

polychromasia

Answer 25

RBCs exhibit a bluish tint

Question 26

hypochromasia

Answer 26

decreased staining bc of insufficient hemoglobin

Question 27

hyperchromasia

Answer 27

cells appear darker

Question 28

rouleaux

Answer 28

grouping of RBCs in stacks
seen with increased fibrinogen/globulin

Question 29

agglutination

Answer 29

clumping of RBCs
seen with immune-mediated disorders
microscopic or macroscopic

Question 30

poikilocytosis

Answer 30

variations in cell shape

Question 31

acanthocytes

Answer 31

irregularly spiculated RBC

Question 32

echinocytes

Answer 32

regularly spiculated cells

Question 33

ghost RBC

Answer 33

lysed RBC, results from rupture of membrane

Question 34

schistocytes

Answer 34

RBC fragments

Question 35

siderocytes

Answer 35

aggregates of iron, focal blue/gray inclusions, siderotic granules

Question 36

spherocytes

Answer 36

sphered RBC
darkly staining RBCs with reduced or no central pallor

Question 37

stomatocytes

Answer 37

RBC with slit central pallor
occurs due to folding of excess membrane

Question 38

RBC inclusions

Answer 38

heinz bodies
nucleated RBCs
howell-jolly bodies
parasites

Question 39

Heinz Bodies

Answer 39

refractive or red inclusions in RBC
indicate oxidant injury to hemoglobin

Question 40

Howell-Jolly Bodies

Answer 40

basophilic nuclear remnants seen in young erythrocytes

Question 41

nucleated erythrocytes

Answer 41

represent early release of immature cells during anemia