White Blood Cell Pathophysiology
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Transcript White Blood Cell Pathophysiology
White Blood Cell
Pathophysiology
Presented by: Wanda Lovitz, APRN
Objectives: WBCs
•Discuss the components of the hematologic system.
•Define and explain hematopoiesis.
•Compare and contrast the five types of leukocytes:
1.Neutrophils
2.Lymphocytes
3.Monocytes
4.Eosinophils
5.Basophils
•Differentiate between the two types of neutrophils:
1.Segs
2.Bands
•Describe how the hematologic system is clinically evaluated:
1.Bone marrow aspiration
2.Bone marrow biopsy
•Briefly describe the various medical disorders that result from alterations
in leukocyte function:
1.Infectious mononucleosis
2.Leukemia
3.Lymphoma (Hodgkins and non-Hodgkins)
Drugs to Know
filgrastim (Neupogen)
Components of the
Hematologic System
Composition of Blood:
Plasma
Plasma proteins
albumin
Blood cells
FORMED IN BONE MARROW
“HEMATOPOIESIS”
Erythrocytes
Leukocytes
Thrombocytes
Composition Of Blood
Fresh Frozen Plasma
(FFP)
►►►
WBC/
Plts
Plasma: 55%
Leukocytes & Thrombocytes: <1%
Erythrocytes: 45%
Primary Function of Blood Cells
Erythrocytes = OXYGEN transport
LEUKOCYTES = protect body from INFECTION
Platelets = promote blood COAGULATION
Transfusing Blood Products:
platelets, whole blood, packed cells,
albumin, and fresh frozen plasma
Structure of the Immune System
Skin - first line of defense
Mucous membranes - first line of defense
Mononuclear phagocyte system
Lymphoid system (spleen, thymus, lymph nodes)
Bone marrow
All structures contain different types of WBCs that
control inflammation and immunity
Chemical mediators aid in defense of the body
complement
kinins
clotting factors
cytokines
chemokines
Lymphoid
Primary
THYMUS
Key in newborn immune response
BONE MARROW *
organs
Red/yellow; origin of hematopoiesis
Secondary
SPLEEN
Fetal hematopoiesis; has phagocytes; has lymphocytes
(immune); blood reservoir
LYMPH NODES
Filters pathogens;
TONSILS
enlarged/tender with infection (r/t macrophages)
Mass of lymph tissue
PEYER PATCHES of small intestine
Lymphoid Organs:
(Link hematologic & immune
system)
Bone Marrow
Confined to cavity of bone
Red (active)
Yellow (inactive)
Not all bones have red marrow
By adulthood the following do:
Pelvic bone
Ribs
Vertebra
Sternum
Extreme proximal portion of humerus/femur
Cranium
Manufactures billions of WBC’s
Spleen Location = upper left quadrant
Enlarged spleen = spleenomegaly
Palpating For Splenomegaly
Development of Blood Cells
“HEMATOPOIESIS”
Defined: blood cell production
Originates in bone marrow
Each type of cell has parent cells → “STEM CELLS”
Two-stage process
MITOTIC division (or proliferation)
Replication of SAME cell
MATURATION (or differentiation)
Differentiates cells
Stem Cells: The Origin Of All Blood Cells
HEMATOPOIESIS
Pluripotential Stem Cell
MYELOID Stem Cells
Granulocyte;
Macrophage
Stem Cells
Granulocyte
Stem Cells
Megakaryocytic
Stem Cells
LYMPHOID Stem Cells
Erythropoietic
Stem Cells
Monocytic
Stem Cells
agranulocytes
NEUTROPHILS MONOCYTES &
EOSINOPHILS MACROPHAGES
& BASOPHILS
Megacaryocytes
& Platelets
Erythrocytes
LYMPHOCYTES
(T cells, B cells,
plasma cells)
Leukocytes (WBCs)
Defined:
Are WBC’s that defend the body against
organisms that cause infection and remove debris,
including dead or injured host cells of all kinds
Act primarily in TISSUES but are transported via
circulation
Average number in adult:
5,000-10,000/mm³
Never Let Monkeys Eat Bananas!
The
five types of leukocytes, in order of prevalence
Never
(NEUTROPHILS)
Let
(Lymphocytes)
Monkeys
(Monocytes)
Eat
(Eosinophils)
Bananas
(Basophils)
Phagocytes = Neutrophils, Monocytes, Eosinophils, Basophils
The Process Of Phagocytosis
“Attack, Engulf, Destroy”
Clinical Evaluation of the
Hematologic System
Blood tests → CBC (# RBC, WBC & platelets)
Complete blood cell count WITH DIFFERENTIAL
includes:
→ RBC Platelets WBC WITH differential count
CBC With Diff OR WBC With Differential
Bone Marrow Aspiration/Biopsy: A Painful Procedure
Leukocytes:
2 Ways To Classify
Structure:
Granulocytes (Lifespan = 1-10 days)
Agranulocytes (Lifespan = days – months – years)
Neutrophils, eosinophils, basophils
Monocytes, lymphocytes
Function:
PHAGOCYTES (cells that ingest/digest bacteria)
Neutrophils, eosinophils, basophils, monocytes
IMMUNOCYTES (cells that create immunity)
Lymphocytes
WBC: Total Count
5,000 -10,000/mm³
WBC ↔ leukocytosis
WBC ↔ leukopenia
neutrophils ↔ neutropenia
Marked granulocytes ↔ agranulocytosis
Total count:
Indicates THE DEGREE of response to a pathologic process
However, differential count will provide a more complete evaluation for
SPECIFIC DIAGNOSES
WBC: Differential
Why Reported in %?
% in one type will ALWAYS mean % in another type even
though absolute number for second type of cell does not
EXAMPLE:
Client with WBC of 10,000/mm³
neutrophil count is 60%
lymphocyte count is 30% (& 10% of others)
Even though lab doesn‘t report actual number of lymphocytes, one can
deduce this client has 3,000 lymphocytes/mm³
called the “ABSOLUTE COUNT”
Example: Continued
If this same client gets a severe BACTERIAL
infection, WBC → 20,000/mm³
In a bacterial infection, almost all of in WBC will
be 2° NEUTROPHILS
Diff count now shows:
→75% neutrophils & 15% lymphocytes
But does NOT mean man has fewer lymphocytes
Example: Continued
He has 15% of 20,000
(or 3,000 lymphocytes/mm³, just as before)
Only PROPORTIONS have changed
Remember:
Absolute numbers may change
Proportions of each type of WBC may change, BUT…
Percentage must ALWAYS add up to 100%
“WBC W/Diff”:
What are we differentiating?
Granulocytes (phagocytes)
Lymphocytes
Neutrophils (50-67%)
Eosinophils (0-3%)
Basophils (0-2%)
(agranulocytes)
(24-40%)
Monocytes/macrophages (agranulocytes)
(4-9%)
{Remember…differential ALWAYS adds up to 100%}
Neutrophils aka “neuts”
Most numerous and best understood of the granulocytes
First to arrive at site of inflammation (within 90 mins)
IMMATURE neutrophils → “bands”
MATURE neutrophils → “segs”
Segs (47-63%)+ bands (0-4%) = 47-67%
CHIEF PHAGOCYTES OF ACUTE INFLAMMATION
with acute bacterial infections & trauma
Neutrophil: Segs & Bands
“Seg”mented neutrophils:
Band neutrophils:
Mature
IMMATURE; few normally found in peripheral blood
A “SHIFT TO THE LEFT”:
Signals ACUTE stage of infection
Means that many band cells are present in peripheral blood
Example: segs = 48%, bands = 14%
“Shift To The Left”: Many neutrophils, but not all of them mature
* Bands are horseshoe-shaped
Neutropenia
Defined: low neutrophil count (absolute count < 1000/mm³)
Most often cancer patients (as a result of disease or treatment)
Susceptible to bacterial infection (can be life-threatening)
“NEUTROPENIC PRECAUTIONS”
Pt wears mask when outside of room
Door closed/sign on the door
Meticulous handwashing
Ø sick visitors
Ø raw fruit, veggies, fish
Remove stagnant water BID
Assess T q4h; any temp is significant
Often do not develop fever (or any other s/s infection) because do not have enough WBC to
produce these reactions; T > 100.4°? Antibiotics < 1 hr
S/P Organ Transplant: Neutropenic Precautions
Leukopenia:
Pharmacologic Treatment
Hematopoietic agents (HA)
Granulocyte - Colony stimulating factors (G-CSF)
filgastrim (Neupogen)
MOA: promotes proliferation, differentiation & activation of cells
that make granulocytes
Indications malignancies, chemo-induced leukopenia
Given IV/SQ.
Adverse Reactions: Bone pain
Nursing Implication: Monitor CBC with differentiation
Lymphocytes
24-40%
The “IMMUNE” WBC
Divided into 2 types: (both formed in bone marrow)
1. T cells → mature in THYMUS; cell-mediated immune
response (attack & destroy specific foreign cells)
2. B cells → mature in BONE MARROW
produce ANTIBODIES that react against foreign antigens (ie., bacteria &
viruses)
Immune Response Cells
T and B cells are the primary cells of immune response (create
immunity)
Fight CHRONIC bacterial infection & ACUTE VIRAL
infections
Most located in LYMPHOID tissue (NOT in bloodstream)
Monocytes
4-9%
Major function → potent phagocytosis
Fight bacteria similar to neutrophils
Second to arrive at the scene of an injury (occur
during LATE PHASE of infection)
Only present in blood for a short time before they
migrate into tissues & become macrophages
Eosinophils
0-3%
Function: phagocytosis of antigen-antibody complexes
with allergic reactions & parasitic infections
Examples: Asthma, drug reactions, severe posion ivy reaction
“Worms,
Wheezes, and Weird diseases”
Basophils
0-2%
Function: PHAGOCYTOSIS
Conditions That Alter WBC’s:
Leukocytosis ( WBC)
Leukopenia ( WBC)
Bone marrow depression
to physiologic stressors
Drug toxicity
(ie, surgery, anesthesia)
Autoimmune disease
Normal protective response
All types of infection
Tissue necrosis
(Lupus)
Malignancies,
Chemotherapeutic agents
Inflammatory disorders
CBC With Diff: NORMAL RANGES
CBC
(RBC, Hgb, Hct, Platelet count)
WBC count
5-10,000/mm³
WBC differential
SEGMENTED NEUTROPHILS
Band neutrophils
Lymphocytes
47-63%
0-4%
24-40%
Monocytes
4-9%
Eosinophils
0-3%
Basophils
0-2%
Example: WBC Diff With Bacterial Infection
CBC
(RBC, Hgb, Hct, platelet count)
WBC count
13,300/mm³
WBC differential
Segmented neutrophils
70%
Band neutrophils
8%
Lymphocytes
15%
Monocytes
4%
Eosinophils
2%
Basophils
1%
Example: Infectious Mononucleosis (Type of Virus)
CBC
(RBC, Hgb, Hct, platelet count)
WBC count
14,200/mm³
WBC differential
Segmented neutrophils
26%
Band neutrophils
4%
Lymphocytes
59%
Monocytes
8%
Eosinophils
2%
Basophils
1%
Example: Allergic Reaction With Resultant Asthma Attack
CBC
(RBC, Hgb, Hct, platelet count)
WBC count
11,700/mm³
WBC differential
Segmented neutrophils
39%
Band neutrophils
7%
Lymphocytes
Monocytes
Eosinophils
Basophils
Worms,Wheezes, and Weird Diseases
29%
3%
22%
1%
What else to look for with an
infection?
temperature
Fever is not a disease, but a sign that the
body is responding to an infection
A fever may or stop growth of some
microorganisms
some can only survive within a narrow range of
temperature
Inflammation
Increased vascular permeability
Leukocyte recruitment and emigration
CHEMOTAXIS- process by which neutrophils are attracted to
inflamed tissue
Phagocytosis of ANTIGENS- neutrophils and macrophages produce
enzymes that digest protein structures
CHRONIC INFLAMMATION
Fibrosis and scarring can occur with prolonged inflammation when
normal tissue is replaced with fibrous tissue
Ex. Pulmonary fibrosis
Granuloma- accumulation of macrophages, fibroblasts and collagen
EX: Tuberculosis
Inflammatory Exudates
Functions: 1) transport leukocytes and antibodies; 2)
dilution of toxins; 3) transport of nutrients for repair
Types:
1) serous- watery, low protein, mild inflammation;
2) serosanguineous- pink tinged fluid, small amounts of RBC;
3) fibrinous- large amount of protein, increased inflammation,
sticky and thick, may need to be removed to allow healing- scar
tissue may develop;
4) Purulent (pus)- severe inflammation, composed of neutrophils,
protein, and tissue debris;
5) Hemorrhagic- large component of RBC, most severe
inflammation
Systemic Manifestations of
Inflammation
C-reactive proteins (CRP)- an acute phase
protein that can be measured in the blood
Erythrocyte sedimentation rate (ESR)- simple
measure of inflammation, measures how
quickly RBC settle to the bottom of a test
tube
Infectious Mononucleosis
Self-limiting lymphoproliferative disorder
Caused by Epstein-Barr virus (EBV)
Most prevalent in adolescence/young adults
Main mode of transmission →
EBV-
contaminated saliva
Pathogenesis: atypical lymphocytes proliferate
Onset: insidious; incubation 4-8 weeks
Mono: Sore throat with erythema & white exudate
Infectious mononucleosis
Clinical manifestations: lymphadenopathy,
hepatomegaly, splenomegaly
Labs:
WBC (~ 12-18,000); 95%
lymphocytes
(viral infection)
Acute phase: 2-3 weeks
Treatment: symptomatic & supportive
Some degree of debility/lethargy: 2-3 months
Leukemias
Acute
ALL (acute lymphocytic leukemia)
AML (acute myelocytic leukemia)
Chronic
CLL (chronic lymphocytic leukemia)
CML (chronic myelocytic leukemia)
DEFINED BY:
1. SITE OF ORIGIN
a. myeloid stem cell
b. lymphoid stem cell
2. ACUTE VS CHRONIC
a. acute
b. chronic
Leukemias
Malignant neoplasms of cells originally derived from a
single hematopoietic cell line
Leukemic cells:
Are immature & unregulated
Proliferate in bone marrow
Circulate in blood
Infiltrate spleen, lymph nodes & other tissues
Disease of children & adults
Common feature of all leukemias:
Uncontrolled proliferation of immature leukocytes
results in crowding out of mature blood cells
including leuckocytes, red blood cells, and platelets
Pancytopenia = decrease in all functioning blood
cells: anemia, thrombocytopenia, neutropenia
HEMATOPOIESIS
Pluripotential Stem Cell
Myeloid Stem Cells
Granulocyte;
Macrophage
Stem Cells
Granulocyte
Stem Cells
Megakaryocytic
Stem Cells
Lymphoid stem cells
Erythropoietic
Stem Cells
Monocytic
Stem Cells
Neutrophils Monocytes &
Eosinophils Macrophages
& Basophils
Megacaryocytes
& Platelets
Erythrocytes
Lymphocytes:
(T cells, B cells,
plasma cells)
Leukemia: Classifications
Classified according to their PREDOMINANT CELL type
LYMPHOCYTIC or MYELOCYTIC AND
whether dx is ACUTE or CHRONIC
1.
Acute lymphocytic (lymphoblastic) leukemia (ALL)*
2.
Chronic lymphocytic leukemia (CLL)**
3.
Acute myelocytic leukemia (AML)
4.
Chronic myelocytic leukemia (CML)
* Most common childhood leukemia
**Most common leukemia of older adults
Leukemia: Pathogenesis
Causes:
Unknown; exposure to radiation
Pathogenesis – Leukemic cells:
Are an immature type of WBC
Capable of rate of proliferation/have prolonged
life span
Cannot perform function of mature leukocytes →
are ineffective as phagocytes
Interfere with maturation of normal bone marrow cells
(including RBC & platelets)
Leukemia: Acute vs Chronic
Acute:
Sudden, stormy onset
S/S related to (mature) WBC, RBC, platelets
ALL → 80% childhood acute leukemias
AML → chiefly an adult disease
Diagnosis based on:
Blood/bone marrow tissue ↔ presence of immature WBC’s (blasts) –
may constitute 60-100% of cells
Leukemias: Acute vs Chronic
Chronic
More insidious onset
May be discovered during a routine medical exam by a blood
count
CLL → older adults
Relatively mature lymphocytes that are immunologically incompetent
CML → adults & children
Leukocytosis with immature cell types
Malignant Lymphomas:
Neoplasms Of Cells Derived From
Lymphoid Tissue
Hodgkin’s disease
Characterized by
Non-hodgkin’s
disease
PAINLESS, progressive,
Also neoplastic disorder of
lymphoid tissue
However, SPREADS EARLY
→ liver, spleen & bone marrow
Also characterized by painless,
superficial lymphadenopathy;
also extranodal symptoms
POORER PROGNOSIS than
Hodgkin’s
rubbery enlargement of a
single node or group of
nodes – usually in neck
area
Reed-Sternberg cell –
distinctive tumor cell found
with lymph biopsy
GOOD PROGNOSIS
Lymphadenopathy: Locations
Cell-specific Leukemias
Pluripotential stem cell
Acute undifferentiated leukemia
Lymphoid stem cell
Acute erytholeukemia
Hodgkins lymphoma
Acute lymphoblastic leukemia
Acute
megakaryocytic
leukemia
Erythroid stem cell
Chronic lymphocytic
Acute
myelocytic
leukemia
Granulocytic stem cell
Megakaryocytic
stem cell
Promonocyte
Chronic myelocytic
leukemia
Poycythemia
vera, chronic
myelocytic
leukemia
Monocyte
leukemia
Chronic granulocytic
leukemia
B-cell
T-cell
Erythrocyte
Multiple
myeloma
Eosinophil
Megakaryocyte
Non-Hodgkin
lymphoma
Myeloblast
Plasma cell
Basophil
Promyelocyte
Humoral immunity (antibody)
(IgG, IgM, IgA,
IgD, IgE)
Cell-mediated
immunity, graft vs
host response
Platelet
Myelocyte
Metamyelocyte
Segmented neutrophil