Lab Practicum Study Guide

[liveonearth]

KEY QUESTIONS AT TOP

Name a small, round fragment in the nucleus that is composed of DNA.
Howell Jolly body

What cells may have Howell Jolly bodies?
RBCs

Name three conditions in which Howell-Jolly bodies may be found.
megaloblast, sickle, spleenectomy, radiation, severe hemolytic, hereditary spherocytosis, and myelodysplastic syndrome

What else might you find in the peripheral blood with in post spleenectomy, B12/folate deficiency, May-Hegglin or leukemic myelofibrosis patients?
giant platelets

What cell is proliferating in Waldenström macroglobulinemia and multiple myeloma?
plasma cells
they also proliferate in plasmacytoma and plasma cell leukemia (duh)

What do neutrophils, monocytes, macrophages, dendritic & mast cells have in common?
they are all phagocytic

What kind of anemia may show macrocytes, teardrop cells, spherocytes?
pernicious anemia

What's the scientific name for teardrop cell?
Dacrocyte

In what conditions may one see dacrocytes?
bone marrow dz incl all forms of myelofibrosis, and pernicious anemia according to Wig

What's the scientific name for a target cell?
Codocyte

What are some conditions where you see codocytes?
codocytes appear whenever a person can't get adequate HGB into RBCs
liver dz, IDA, thalassemias, HGB C dz, post-splenectomy incl dt sickle cell anemia

What's the scientific name for a sickle cell?
Drepanocyte

What is the order of development fro cells in the myelocitic erythrocyte lineage?
blast-->pro-cyte-->cyte-->meta-->band-->baso/eo/neut

What % of the blood is normally eosinophils?
1-3%

REVIEW QUESTIONS FROM HERE DOWN

Where do all blood cells originate?
the bone marrow, where they differentiate from totipotent cells into the the two hematopoietic progenitor cell lines (myeloid and monocytic), and continue to differentiate into all the different kinds of white blood cells, red blood cells, and platelets.

In normal blood cell development what occurs to the size of the nucleus?
it shrinks

How would you characterize the nuclear-to-cytoplasmic ratio of immature blood cells?
the nucleus takes up more of the cell, so the ratio is high, when the cell is immature
as the cell matures the nucleus shrinks and the cytosol is a bigger fraction
so the radio is lower

What is the most reliable criterion of the level of maturation of a blood cell?
the state of the nucleus and density of chromatin

What is the significance of the nucleoli in the nucleus of a developing blood cell?
A nucleolus is a non-membrane bound area inside the nucleus where the DNA coding for ribosomes is read, and the resulting RNA is modified until ribosomes are manufactured. Ribosomes are where mRNA and rRNA come together to manufacture proteins, so ribosomes must be built before the rest of the cellular machinery can begin. Hence the need and timing of nucleolus presence should be obvious, and it does not matter whether it is on the test or not!!!

Know which populations (immature and mature) have granules.
Immature cells such as promyelocytes have granules
Mature "granulocytes" such as neutrophils, eosinophils, basophils also have granules
Myeloblasts DON'T have any

Know the names and correct order for the maturation sequence of the myelocytic WBCs.
blast-->pro-cyte-->cyte-->meta-->band-->baso/eo/neut
blast = has no granules
pro-cyte = has primary granules
cyte = has secondary granules, neutrophilia dawns
meta = nucleus starts to indent
band = nucleus indented more than 1/2 diameter
baso/eo/neut has segmented nucleus and specialized granules

What two dyes make up the Wright’s stain?
methylene basic blue and eosin acid

When does a myeloblast become a promyelocyte?
when it develops primary granules and is azurophilic

When does a promyelocyte become a myelocyte?
when it forms secondary granules with varying dye affinity

What is the “dawn of neutrophilia”?
p2
first sign of neut differentiation is development (in cytoplasm and adjacent to nucleus) of small, relatively light island of ill-defined specific pinkish neutrophilic granules. Light area of secondary granules has been called the "d of n". Cell is identified as a neutrophilic myelocyte at this point, but some azurophilic primary granules are still present. They fade away and the neutrophilic granules dominate.

What is the normal range for neutrophilic bands in a healthy adult?
1-5% in peripheral blood
10-40% in marrow

What is meant by a “shift to the left”?
increased immature neuts in peripheral blood usudt infx

In which conditions might one see hypersegmented neutrophils?
(hyperseg = 5 or more lobes)
p4
may see one in normal blood--
they are up to 2% of neuts in healthy older children and adults
also, increased in these conditions:
acute infections
inflammatory processes
intoxication
vigorous exercise
malignant neoplasms
myeloproliferative dz
acute hemorrhage
acute hemolysis

Are hypersegs pathognomonic in any conditions?
megaloblastic anemia caused by failure of bone marrow blood-forming cells to make DNA

Know the definition of a band.
An immature neutrophil with the nucleus indented in a C shape, the dent being greater than 1/2 the diameter of the whole nucleus

When does a myelocyte mature into a metamyelocyte?
p3
when it is done dividing mitotically and ready to differentiate
nucleus begins to indent, up to the radius of the nucleus
nuclear chromatin moderately dense with some clumping at nuclear periphery
you shouldn't see these in peripheral blood

What is the characteristic feature of neutrophils in Pelger-Huet anomaly? Hypolobulation: 2 lobes (instead of 3-4 which is normal)
P-H = rare genetic disorder with an autosomal dominant inheritance pattern
a blood laminopathy assoc w/ lamin B receptor (prob w/ prots in nuclear lamina)
heterozygotes clinically normal but
their neuts mb mistaken for immature cells-->mistreatment in a clinical setting
Homozygotes have neutrophils with rounded nuclei that do have some functional problems.

When might toxic granulation be seen in neutrophils?
severe infxn (sepsis)
high fever
tg's are dark coarse granules found in granulocytes, esp neuts
also find Dohle bodies and cytosolic vacuolation in the cytoplasm
Dohle bodies are about 3 micrometer long rods thought to be remnants of rough ER

Auer rods are found in which blood cells?
in the leukemic blasts of acute myeloid leukemia
Auer rods = clumps of azurophilic cigar-shaped granules in cytoplasm of leuk blasts
composed of fused lysosomes
contain peroxidase, lysosomal enzymes, and large crystalline inclusions

What is the normal range for eosinophils in a healthy adult?
1-3% of peripheral blood

Know which of the WBCs are phagocytic.
phagocytes eat stuff
discoverer of phagocytes got Nobel prize for medicine in 1908
called "professional" or "non-professional"
professional phagocytes: neutrophils, monocytes, macrophages, dendritic & mast cells
professional phagocytes have receptors to detect invaders
nonprofessional: can't recognize opsonized material and don't make ROS
nonprofessional: epithelial cells, endothelial cells, fibroblasts, mesenchymal cells!
fibroblasts eat old collagen!!

Name the two main chemicals found in the granules of basophils.
heparin, histamine and chondroitin (proteoglycans)
they secrete lots of enzymes but those are not premade & stored in granules,
they are made on site

Name three conditions in which a higher than normal percentage of basophils may be found in peripheral blood.
p5
CML = chronic myelocytic leukemia esp in terminal blast transformation
basophilic leukemia
lymphoma
myxedema
(also chronic sinusitis, smallpox, chicken pox, and ulcerative colitis)

Which 3 cells are key in the body’s first line of defense against pathogenic organisms? neuts, monos, macrophages

What gives the cytoplasm of a monocyte its characteristic “ground glass” appearance? azurophilic granules
vacuoles filled with enzymes

What are the two main classic nuclear features of the monocyte?
deeply indented, horse-shoe shaped nucleus
brain-like convolutions of chromatin

What is the normal range for monocytes in a healthy adult peripheral blood?
1-6%

What are the three most characteristic features of a monocyte?
ground glass appearance
horseshoe shaped nucleus
brain-like convolutions of chromatin

What 3 things are most helpful in determining a monocyte from a large lymphocyte?
ground glass, horseshoe, brainlike chromatin AND
monocytes have vacuoles and pseudopods

What is the cell organelle that may appear as distinct bluish-red granules in the cytoplasm of monocytes and large lymphocytes?
???
Nucleoli?

What is the normal range for lymphocytes in young children?
30-70%
(adults 20-40%)

Why is it higher than the normal range in older children and adults?
p.11 kids are in process of developing immunity
most but not all large granular lymphocytes are known as the natural killer cells (NK)
small lymphocytes are the T cells and B cells

Nucleus of a small lymphocyte is comparable in size to which other blood cell?
RBC

What are the two characteristics of the nucleus of a mature lymphocyte?
p.11
small, round nucleus
dense chromatin
rim of blue nongranular cytoplasm

Are small mature lymphocytes capable of responding to antigenic stimuli?
yes, they are B and T cells!

Name four conditions in which one might see reactive lymphocytes.
EBV, CMV, toxoplasma, Treponema pallidum, Hep C, Hantavirus
radiation, stress, autoimmune dz

Where do blood cells first appear in fetal life?
differentiated from mesoderm
week 4-5 "rudimentary blood" circulates in main vessels (what is this?)
week 9-12 RBC's are produced in the liver
weeks 21-23 blood cells begin to be produced by bone marrow
source: http://www.nlm.nih.gov/medlineplus/ency/article/002398.htm


Which type of lymphocyte is responsible for cell-mediated immunity?
T cells (small lymphocytes), and NK cells (large, granulocytic lymphocytes)
(macrophages are from the monocyte lineage)

Which type of lymphocyte is responsible for humoral immunity?
B cells make antibodies that float around in the humor and opsonize things

What is the normal percentage of T cells in healthy adult peripheral blood?
70-80% of lymphocytes

What is the normal range for plasma cells in healthy adult peripheral blood?
none

Name four conditions that are characterized by the proliferation of plasma cells.
plasma cell leukemia
Waldenström macroglobulinemia
plasmacytoma
multiple myeloma

At which stage in the normal maturation sequence of RBCs is hemoglobin usually visible as a distinct reddish color in the cytoplasm?
in the basophilic erythroblast

What is the last stage in the normal maturation sequence of RBCs that has a nucleus? orthochromatic erythroblast
= nucleated precursor cell in the erythrocytic series---four stages:
1) proerythroblast
2) basophilic e. (cytoplasm basophili, nucleus lg w/ clumped chromatin, nucleoli are gone)
3) polychromatophilic e. (nuclear chromatin increased clumping, cytoplasm starts accumulating hemoglobin and staining acid)
4) orthochromatic e. (final stage before nuclear loss, nucleus is small and ultimately becomes a blue-black, homogeneous, structureless mass)
source: http://medical-dictionary.thefreedictionary.com/orthochromatic+erythroblast

What is responsible for the bluish color in the cytoplasm of diffusely basophilic erythrocytes?
Heparin and histamine??? not sure about this answer

What are the predominant RBC shapes seen in pernicious anemia?
macrocytes, teardrop cells, spherocytes

What's the other name for teardrop cell?
Dacrocyte

Name three conditions in which one might see microcytic RBCs.
IDA, thalassemia, sideroblastic anemia (body has iron but can't put it in HGB)
sideroblast = atypical nucleated erythrocytes with granules of iron accumulated in perinuclear mitochondria
thalassemia = faulty or missing globin chains

What are the three characteristic features of thalassemia major?
p.22
microcytic/hypochromic anemia
target cells
basophilic stippling

Name three conditions in which one might see target cells on a peripheral smear.
thalassemia
sickle-cell anemia
Hb-S thalassemia
other hemoglobinopathies

What comprises the reticulum within reticulocytes?
a reticular (mesh-like) network of ribosomal RNA
that becomes visible under a microscope with certain stains
such as new methylene blue

What does basophilic stippling represent?
usu lead poisoning
nutritional deficiencies
use of cytotoxic drugs

Name two conditions where basophilic stippling may be found.
p.16
heavy-metal intoxication
nutritional deficiencies
use of cytotoxic drugs

What are Howell-Jolly bodies?
small, round nuclear fragment composed of DNA

Name three conditions in which Howell-Jolly bodies may be found.
megaloblastic anemia
sickle-cell anemia
post spleenectomy

What are Heinz bodies?
denatured hemoglobin
seen as round, blue precipitates or inclusions

Where do you find Heinz bodies?
in stained RBCs

Name three conditions in which Heinz bodies may be found.
G-6-PD deficiency
drug toxicity
unstable and abn HGB

What is the normal size range for platelets?
2-3 microns
micrometre = micron = µm = 1 millionth of a metre = 1/1000 of a millimetre = 1×10−6 m

What method would one use in order to estimate the number of platelets per cubic millimeter of blood when looking at a stained smear of blood?
p. 9
(PLTS/HPF) x 20

Name four conditions in which one may see giant platelets.
post spleenectomy
B12/folate deficiency
May-Hegglin
leukemic myelofibrosis

What is May-Hegglin anomaly (MHA)?
a rare genetic disorder of giant platelets and abnormal leukocytes
aka Dohle leukocyte inclusions with giant platelets
and macrothrombocytopenia with leukocyte inclusions

Other keypoints:
Remember RBCs have RNA, not DNA
Mesenchymal cells are the very, very beginning
Only use oil immersion at 100 (not 40x)
Dohle bodies: inconspicuous pale, sky-blue cytoplasmic inclusions, RER residual aggregates, but may increase in infectious dz, burns, cytotoxic chemical, poisons.
Eos will have colorless cytoplasm with big orange granules
Humoral immunity is for viral infections (B cells)
Codocytes (target cells): seen in thalassemia, sickle-cell anemia, and other hemoglobinopathies, liver disease and abN hemoglobin structure
Activated monocytes have a perinuclear clearing zone
Judge a cell by the company it keeps
Azurophilic granules = toxic granules
Stomatocytes aka helmet cells: alcoholism, cirrhosis, obstructive liver disease
Spherocytes: transfusions, burns, hemolytic anemia

Slide portion of the test will be on the exact same slides shown in class.

Additional info:
50-70% Neutrophils
20-40% Lymphocytes 7-10 microns
1-6% Monocytes 12-20microns
1-3% Eosinophils 10-15microns major basic protein, eosinophilic cationic pro.
0-1% Basophils 10-15microns heparin and histamine
RBCs 5-7microns
Platelets 1-3 microns serotonin, histamine, L-tryptophan