hematology Flashcards
CBC and component tests report what
the numbers, size and shape of the various cells in the blood
red cells transport what
oxygen
WBC function is what
part of defense against unwanted intruders
e.g. bacteria and viruses
platelets maintain the integrity of what system
vascular system
how do platelets mainitan integrity of vascular system
by plugging leaks in blood vessels
what is the fluid component of blood called
plasma
what makes plasma
about 55% of blood volume
90% water
blood cells are produced from what
a precursor cell in bone marrow
what is hematocrit
percent of whole blood volume occupied by RBCs
hematocrit lab values
male 38.8 - 50%
female 34.9 - 44.5%
what is hemoglobin
protein in RBCs that carriers oxygen to blood
hemoglobin lab values
male 13.5 - 17.5 g/dl
female 12 - 15.5 g/dl
hemoglobin ratio to hematocrit
1/3
what are reticulocytes
new RBCs recently release from bone marrow
immature RBCs
reticulocytes test what
test activity of bone marrow and need for RBCs
how are reticulocytes reported
as a percent of total red cells (0.5% to 1.5%)
why should you look at reticulocyte count for pt with anemia
to determine if there is a problem originating in bone marrow
what will reticulocyte count look like if bone marrow is doing its job WNL
higher count
optimal range of RBC distribution width (RDW)
13
what does RBW measure
the consistency of the size of RBCs
RBW is often increased in
- pernicious anemia
- folic acid deficiency
- iron deficiency anemia
- hemolytic anemia
- transfusions
- sideroblastic anemia
- alcohol abuse
- hereditary anemias
RBW decreased when
barely
not going to see this a lot with primary care
RBC optimal values
male 4.7 - 5.25 million/mm3
female 4 - 4.5 million/mm3
RBC evaluates what
normal erythropoiesis (production of RBCs)
WBC range
4500 - 11,000
look at WBC when concerned for what
infection, viruses
what is leukocyte
another name for white blood cyte
leukocytosis
WBC elevated
leukopenia
WBC low
name the different leukocytes
- neutrophils
- eosinophils
- basophils
- lymphocytes
- monocytes
what are segemented nuclei or polymorphonuclear leukocytes
neutrophils, eosinophils, basophils
what are non-segmented nuclei
lymphocytes and monocytes
neutrophils are prominent in what
acute infection and inflammatory states
neutrophils increase with what
infection and burns
neutrophils decrease with what
b12 and folate anemia and chemotherapy
eosinophils are important with what
allergic reactions and parasitic infections and leukemias
basophils important with what
allergic response
basophils rise with what
allergies, CML, Hodgkin’s
what are the largest leukocytes
monocytes
what are the most abundant leukocytes
neutrophils
monocytes do what
important role with chronic infections and inflammation
important with fibrocytosis and production of cytokines to help stimulate other WBCs to recruit for fighting infecetion
where are monocytes stored
spleen
what causes increased monocytes
stress response, viral infection, chronic inflammatory states, mono
what are the different types of lymphocytes
B cells, T cells, neutropillar cells
what are the 6th type of WBC
newly produced polymorphonuclear leukocytes are called bands
what is WBC shift to left
when bands and PMNs appear as greater percent of WBCs
high number of immature WBC are present to fight infection/inflammation
where are platelets produced
bone marrow
what to platelets participate in
clotting
red cell indices
MCV
MCH
MCHC
what is mean corpuscular volume (MCV) and the range
average red cells size
80 - 100 fl
what is the most common red cell indices to look at in anemic pt
MCV
what is mean corpuscular hemoglobin (MCH) and range
average mass of hemoglobin per cell
27 - 33 pg (picograms)
what is mean corpuscular hemoglobin concentration (MCHC) and range
average hemoglobin concentration in red cell
33-36 g / dl
CBC uses
- part of comprehensive examination
- baseline test
- differential when serious infection is diagnosed
- repeated to document recovery
- bleeding of any kind
- c/o fatigue, sob, pallor; r/o anemia
- for female c/o increased menses
- pt c/o dark stools
is CBC sensitive and/or specific
sensitive
not specific for particular disease
h/h assess what
seriousness of bleeding post trauma or for other causes of bleeding
anemia is diagnosed with what CBC values
decreased H/H
what does CBC look like with infection or inflammation
WBC rises
what does CBC look like with bacterial infection
shift to left (more neutrophils)
what does CBC look like with infectious mononucleosis
percent of monocytes rise in differential
what can explain bleeding or bleeding tendency
thrombocytopenia
what is thrombocytosis and what is the risk
too many platelets
may increase risk of abnormal clotting and possibly stroke
what does CBC look like with leukemia
elevated WBC with abnoral distribution of the types of white cells
Which is true if blood plasma?
a. 90% water
b. Includes platelets but no other cells
c. Includes platelets and white cells but no red cells
d. Is the liquid component of blood without fibrinogen
a
name cellular components of blood
red cells, white cells, platelets
reticulocytes are new RBCs
name usual white cells in blood
polymorphoneuclear leukocytes (PMNs or just leukocytes), lymphocytes, and monocytes - PMNs are neutrophils, basophils or eosinophils
define blood plasma
liquid component of blood that includes fibrinogen
vitamin b12 normal range
200 - 600 pg/ml
folate normal range
2 - 20 ng/ml
Vitamin b12 and folate are necessary for
red cell production, DNA synthesis and neurological function
Folic acid especially important for development of the fetus during pregnancy
what does deficiency of vitamin b12 or folate cause
diminished production of red cells
what happens to hemoglobin with b12 or folate deficiecny
hemoglobin synthesis is not effected
cells are jam packed full with hgb
red cells are macrocytes0 larger than normal, and hyperchromic (dense red cells)
increase in MCV, > 100
increase MCH
pernicious anemia is caused by what
b12 deficiency
parietal cells in stomach do not produce intrinsic factor necessary for absorption of b12
intrinsic factor antibody +
pernicious anemia
treatment of pernicious anemia
injected supplementation of b12 bc cannot be absorbed in PO form
other causes of folic acid or b12 deficiecny
nutrition deficiency or malabsorption syndrome
vegans, gastric bypass, celiac disease
symptoms of b12 deficency
infertility hypothyroidism depression cognitive decline/ memory loss low energy numbness (neuro)
who is possibly folate deficient
alcoholics
pregnant women
what tests are ordered for macrocytic, hyperchromic anemia
folate and vitamin b 12
b12 levels are ordered for pt with
memory loss, depression, and other neurologic s/s- numbness and tingling
folate levels are ordered for pts who are
alcoholics or pregnant pts or pts with suspected nutritional deficiencies
pt comes in with fatigue or memory loss or neuro symptoms, what do you order
CBC
b12
folate
what is needed to converting homocysteine to methionine and methylmalonyl CoA (MMA) to succinyl CoA
B12 cofactor
when b12 is not available, what levels increase
MMA and homocysteine
what are the best indicators of b12 deficiency
MMA- methionine and methylmalonyl CoA
bc b12 is only coenzyme required in this pathway
what are indirect measures of bone marrow
ferritin, iron level, and total iron binding capacity
necessary for production of hgb
what happens to RBC without sufficient iron
microcytic red cells that are hypochromic
MCV and MCH low
MCV < 80
what is frequently associated with iron deficiency anemia
chronic GI blood loss
is serum ferritin needed when blood loss is documented with stool occult blood tests or site of bleeding is identified
not necessary when you know where bleeding source is
when to order ferritin/iron, iron binding capacity labs
microcytic anemia (low h/h, MCV < 80, microcytic
what do labs look like with iron deficiency anemia
ferritin low iron low TIBC normal or high transferrin sat. low RDW normal or high RBC count low
ferritin normal values
30–300 ng/mL (=μg/L) for males
6–115 ng/mL (=μg/L) for females
mild to moderate iron def anemia
Hgb > 10; Ferritin > 15
severe iron def anemia
hgb < 10, ferritin < 15
aside from iron def anemia, what can low ferritin indicate
- hypothyroidism
- vit C deficiency
- celiac disease
increased ferritin occurs when
inflammatory and neoplastic disorders
eg hepatitis, some tumors, acute leukemia, Hodgkin lymphoma, GI tract tumors
what is first step in evaluation of normocytic anemia
assess clinical hx
Does pt have some dx that would cause anemia of chronic disease?
ie renal insuff, thyroid disease, or other endocrine disease
what should you check to look for early iron deficiency or combined nutritional deficiecny
iron studies
folate/vit b12 levels
what to do if reticulocyte count is increased
do hgb electrophoresis to look for hemoglobinopathy, screen for g6pd defieicny, and direct anticoagulation tst
what to consider if reticulocyte is low
anemia of chronic disease
chronic renal insuff
thyroid disease
marrow damage
if cause of normocytic anemia is not apparent what should be done
bone marrow aspirate and bx
define pernicious anemia
B12 deficiency anemia caused by a lack of intrinsic factor production by the gastric parietal cells - intrinsic factor is necessary for the absorption of B12 in the distal ileum
What would be your concern when an older patient has iron deficiency anemia?
GIB or CA
what labs are included in assessment of clotting
- partial thromboplastin time, PTT
- prothrombin time, PT
- international normalized ratio, INR
- d-dimer
what is partial thromboplastin time, PTT
measure of adequacy of intrinsic or coagulation pathway
what do PT and INR measure
activity of extrinsic pathway and vitamin K dependent clotting factors
is PT or INR more reliable
INR
units of measurement for PTT, PT, INR
PTT and PT reported in units
INR has no units
d-dimer is what
breakdown product of fibrin
when is d-dimer elevated
when clots are lysed either as part of body’s own repair mechanisms or by injected fibrinolytics
how is d-dimer measured
ng/ml or micrograms/L
when is d-dimer used
when there is concern for PE or blood clot (DVT)
to assess treatment of PE or DVT
assess possibility of disseminated intravascular coagulopathy
can d-dimer be used for diagnosis
no, it supports diagnosis
cannot actually diagnose
what should d-dimer look like after receiving treatment
decreased as the clot should have decreased in size
if it remains elevated then there is a high likelihood of recurrence and anticoagulation is continued
is d-dimer used for rule in or rule outs
good for ruling out clotting as cause of symptom
other times d-dimer is positive
- sickle cell
- pregnancy
- some malignancies
- post op
- when rheumatoid factor is elevated
how do false positives affect diagnostic value of d-dimer
limits the diagnostic value
PTT is used to follow what
pt’s coagulation on heparin
not need for low molecular wt heparin, just baseline in this form of treatment
INR is used to assess what
pt’s response to warfarin
how is ventilation/perfusion scan performed
nuclear study
- radioactive marker injected
- circulates in vascular system
- scan done
THEN - pt breaths in radioactive substance
- another scan performed
what does v/q scan look for
concern for PE
looks for mismatch between inhaled scan and vascular scan (inspired radioactivity but no perfusion activity)
how is spiral CT (helical CT or multidetector CT) performed
cuts are made at 2 mm intervals, normally cuts are 5 or more mm
what is spiral CT used for
quick way to visualize the pulmonary arteries where embolus may be lodged
what is gold standard for PE diagnosis
spiral CT (helical CT or multidetector CT)
When is D-dimer formed?
when fibrin in clots break down
which vitamin is necessary for coagulation factors assessed by INR?
vitamin K
what characteristics are different with sickle cells
sickle shapes of red cells as result of abnormal conformation of hemoglobin
cells sickle when oxygen concentration is reduced
sickle cells are stiffer than normal cells
RDW is increased d/t variation in width of red cells
abbreviation for abnormal hemoglobin
HbgS
normal hemoglobin abbreviation
HgbA
what is happening with sickle cells?
When cells become stiffer than normal cells and cause microvascular obstructions and occlusions and get clots and lots of ischemia and pain and organ necrosis and ill
sickle cell trait occurs in people who are what
heterozygous
have normal gene and abnormal gene for hemoglobin
do pts with sickle cell trait show symptoms
no, usually asymptomatic
homozygous for sickle cell gene means what
100% cells are effected
subject to severe symptoms
greater risk for thromboembolism
sickle cell tests are used for what
- screening
- diagnosing
sickle cell trait and sickle cell disease
- genetic counseling
what ethnic origins are most affected with sickle cell
African americans
mediterraneans
sub-suhara africans
Asians
BC of adaptation from Malaria
what kind of testing is needed for pts who have symptoms of repeated microvascular events
sickle cell test
pts are at risk of having sickle cell trait
how to diagnose sickle cell
hemoglobin electrophoresis for definitive diagnosis
What do red blood cells look like with iron deficiency anemia?
hypochromic, microcytic
What does leukocytosis with left shift look like
WBC elevated and abnormally high number of bands
What is mean corpuscular volume, MCV
measure of average size ore red cells
what is blood typing
assessment of different antigens and antibodies in the blood
what is cross matching
identification of blood and blood products to transfuse into pt
what happens if cross matching is not done properly
pt may have mild reaction to blood transfusion or may have serious reaction and die
what requires blood type and cross match
transfusions of whole blood or any of components of blood- red cells, platelets, plasma
what are antigens on red cells referred to
A or B depending on which antigen is present
blood type A- antigens and antibodies
antigens on RBC- A
can donate blood to A, AB
can receive blood from O and A
antibodies to B antigen
blood type B- antigens and antibodies
antigens on RBC- B
can donate blood to B, AB
can receive blood from B, O
antibodies to A antigen
blood type AB
antigens on RBC- A and B
can donate blood to AB
antibodies to none
can receive blood from AB, O
blood type O
antigens on RBC- none
can donate blood to A, B, AB, O
antibodies to A antigen and B antigen
can receive blood from O
what is Rh
another antigen on red cell surface
stands for Rhesus antigen
if present, blood is Rh positive and if negative blood is Rh negative
Define the ABO blood typing group
Red cells have on their surface either antigen A , B or neither in which case their blood is type O
Which antibodies are in the plasma of each ABO blood type?
Type A blood has type B antibodies in the plasma. Type B has type A antibodies. Type AB has neither antibody and type O has both A and B antibodies in the plasma.
