Ch. 12 - Disorders of White Blood Cells

Pathophysiology Exam 2

What are white blood cells (leukocytes)?

Cells of the immune system that protect the body against infection, inflammation, and abnormal cells

Where are white blood cells produced?

Primarily in the bone marrow from hematopoietic stem cells

What are the five major types of white blood cells?

Neutrophils, lymphocytes, monocytes, eosinophils, and basophils

Which white blood cell is the most abundant?

Neutrophils

Which blood cell is the body’s first responder to bacterial infection?

Neutrophils

What is the primary function of neutrophils?

To engulf and destroy bacteria through phagocytosis

What is phagocytosis?

The process by which cells engulf and digest microorganisms or debris

What is neutrophilia?

An increased number of of neutrophils, commonly seen with bacterial infections and acute inflammation

What is neutropenia?

A decreased number of neutrophils, increasing the risk of serious infection

Why are patients with neutropenia at high risk for infection?

Neutrophils are the primary defense against bacteria and many fungi

What are the two major types of lymphocytes?

B lymphocytes (B cells) and T lymphocytes (T cells)

What is the primary function of B lymphocytes?

To produce antibodies as part of humoral immunity

What is the primary function of T lymphocytes?

To provide cell-mediated immunity by coordinating immune responses and destroying infected or abnormal cells

Which lymphocytes produce antibodies?

B cells

Which lymphocytes directly kill virus-infected cells?

Cytotoxic T cells

What are helper T cells?

T cells that coordinate the immune response by activating other immune cells

What happens to helper T cells in HIV infection?

They are progressively destroyed, weakening the immune system

What is lymphocytosis?

An increased number of lymphocytes, commonly seen in viral infections

What is lymphopenia?

A decreased number of lymphocytes

Which infections commonly cause lymphocytosis?

Viral infections such as infections mononucleosis and many respiratory viral illnesses

What is the primary function of monocytes?

To become macrophages in tissues and remove pathogens, dead cells, and debris through phagocytosis

What are macrophages?

Large phagocytic cells derived from monocytes that engulf pathogens and help activate other immune cellsm

What is the primary function of eosinophils?

To defend against parasitic infections and participate in allergic reactions

Which white blood cell is most commonly elevated in parasitic infections?

Eosinophils

Which white blood cell is commonly elevated during allergic reactions such as asthma?

Eosinophils

What is the primary function of basophils?

To release histamine and heparin during allergic and inflammatory responses

What is histamine?

A chemical mediator that causes vasodilation and increases capillary permeability during inflammation and allergic reactions

Why does histamine cause swelling during inflammation?

Increased capillary permeability allows fluid and immune cells to move into the tissues

Which white blood cell releases histamine?

Basophils

What is the easiest way to remember the functions of te five white blood cells?

Neutrophils = Bacteria (first responders, phagocytosis)

Lymphocytes = Viruses and adaptive immunity (B cells and T cells)

Monocytes = macrophages (“big eaters”)

Eosinophils = Parasites and allergies

Basophils = Histamine and allergic reactions

What is a hematologic neoplasm?

A cancer that originates in blood-forming tissues such as the bone marrow or lymphatic ysem

What is leukemia?

A group of cancers characterized by uncontrolled production of abnormal white blood cells in the bone marrow

Why is leukemia considered a bone marrow disease?

Leukemia beings in the bone marrow, where blood cells are produced

How does leukemia affect normal blood cell production?

Abnormal leukemic cells crowd out healthy blood-forming cells, reducing production of normal red blood cells, white blood cells, and platelets

Why do patients with leukemia often develop anemia?

Leukemia suppresses normal red blood cell production in the bone marrow

Why are patients with leukemia at risk for infection?

Although the white blood cell count may be high, the leukemic white blood cells are immature or abnormal and do not function effectively

Why do patients with leukemia commonly develop thrombocytopenia?

Leukemic cells crowd out platelet-producing cells in the bone marrow

What symptoms are associated with thrombocytopenia in leukemia?

Easy bruising, petechiae, prolonged bleeding, epistaxis, and bleeding gums

What are the common signs and symptoms of leukemia?

Fatigue, fever, recurrent infections, bruising, bleeding, pallor, bone pain, weight loss, and enlarged lymph nodes, liver, or spleen

Why is bone pain common becomes packed with rapidly growing leukemic cells, increasing pressure within the bone?

The bone marrow becomes packed with rapidly growing leukemic cells, increasing pressure within the bone

How are leukemias classified?

By the speed of progression (acute or chronic) and the type of white blood cell involved (lymphoid and myeloid)

What is acute leukemia?

A rapidly progressing leukemia involving immature white blood cells (blasts)

What is chronic leukemia?

A lower-progressing leukemia involving more mature but abnormal wihte blood cells

Which type of leukemia is more aggressive?

Acute leukemia

Which type of leukemia develops more rapidly?

Acute leukemia

Which type of leukemia may remain asymptomatic for months or years?

Chronic leukemia

What does “lymphoid” leukemia mean?

The cancer arises from lymphocyte precursor cells

What does “myeloid” leukemia mean?

The cancer arises from myeloid precursor cells that normally develop into neutrophils, monocytes, eosinophils, basophils, red blood cells, or platelets

What does ALL stand for?

Acute Lymphoblastic Leukemia

Which age group is most commonly affected by ALL?

Children

What does AML stand for?

Acute Myeloid Leukemia

Which age group is most commonly affected by AML?

Adults, especially older adults

What does CLL stand for?

Chronic Lymphocytic Leukemia

Which age group is most commonly affected by CLL?

Older adults

What does CML stand for?

Chronic Myeloid Leukemia

What genetic abnormality is classically associated with CML?

The Philadelphia chromosome, which creates the BCR-ABL fusion gene

Why is the Philadelphia chromosome important?

It produces an abnormal tyrosine kinase that causes uncontrolled cell growth

Which medication class specifically targets the abnormal protein in CML?

Tyrosine kinase inhibitors (TKIs), such as imatinib

What laboratory finding is commonly seen in leukemia?

An abnormal white blood cell count (high or sometimes low), often with immature blast cells, along with anemia and thrombocytopenia

How is leukemia definitively diagnosed?

A bone marrow biopsy demonstrating abnormal leukemic cells

What are the primary goals of leukemia treatment?

Destroy leukemic cells, restore normal bone marrow function, achieve remission, and prevent relapse

What is remission?

A period in which signs and symptoms of leukemia disappear and leukemic cells are greatly reduced or absent

What are common treatments for leukemia?

Chemotherapy, targeted therapy, immunotherapy, radiation therapy (selected cases), and hematopoietic stem cell (bone marrow) transplantation

What is hematopoietic stem cell transplant?

Replacement of diseased bone marrow with healthy stem cells to restore normal blood cell production

Why are leukemia patients at high risk for bleeding during treatment?

Chemotherapy suppresses bone marrow, reducing platelet production and worsening thrombocytopenia

Why are leukemia patients at high risk for infection during chemotherapy?

Chemotherapy suppresses bone marrow, causing neutropenia and decreased immune function

What nursing intervention is essential for a patient with severe neutropenia?

Prevent infection through good hand hygiene, avoiding exposure to illness, monitoring for fever, and using protective precautions when indicated

Why is fever considered a medical emergency in a neutropenic patient?

Fever may be the only sign o f a life-threatening infection because the immune response is impaired

What is multiple myeloma?

A cancer of plasma cells that originates in the bone marrow

What are plasma cells?Sp

ecialized B lymphocytes that produce antibodies (immunoglobulins)

What happens to plasma cells in multiple myeloma?

Abnormal plasma cells multiply uncontrollably and produce large amounts of a single abnormal antibody (monoclonal protein or M protein)

How does multiple myeloma affect the bones?

Myeloma cells stimulate bone breakdown, causing osteolytic lesions, bone pain, and fractures

What is the most common symptom of multiple myeloma?

Persistent bone pain, especially in the back, ribs, pelvis, or skull

Why are fractures common in multiple myeloma?

Osteolytic lesions weaken the bones, making them prone to pathological fractures

Why does multiple myeloma commonly cause hypercalcemia?

Bone destruction releases calcium into the blood stream

Why can multiple myeloma lead to kidney damage?

Abnormal monoclonal proteins can accumulate in and damage the kidneys

What are common signs and symptoms of multiple myeloma?

Bone pain, fractures, fatigue, anemia, recurrent infections, hypercalcemia, and kidney dysfunction

Why are infections common in multiple myeloma?

Abnormal plasma cells produce ineffective antibodies and suppress normal immune function

Why Is lymphoma?

A cancer of lymphocytes that originates in the lymphatic system

What is Hodgkin lymphoma?

A lymphoma characterized by the presence of Reed-Sternberg cells

What are Reed-Strernberg cells?

Large, abnormal B lymphocytes that are the hallmark of Hodgkin lymphoma

What is the most common presenting sign of Hodgkin lymphoma?

Painless enlargement of one or more lymph nodes, often in the neck

What are the “B symptoms” of Hodgekin lymphoma?

Fever, drenching night sweats, and unexplained weight loss

How does Hodgkin lymphoma typically spread?

In an orderly, predictable fashion from one lymph node group to the next

What is Non-Hodgekin lymphoma (NHL)?

A diverse group of lymphoid cancers that do not contain Reed-Sternberg cells

How does Non-Hodgekin lymphoma typically spread?

In a less predictable pattern and may involve multiple lymph node groups and extra nodal tissues early

What are common signs and symptoms of Non-Hodgekin lymphoma?

Painless lymph node enlargement, fever, night sweats, weight loss, fatigue, and symptoms related to the organs involved

What is the major pathological difference between Hodgkin and Non-Hodgkin lymphoma?

Hodgkin lymphoma contains Reed-Sternberg cells, while Non-Hodgkin lymphoma does not

Which lymphoma generally spreads in a more predictable, contagious pattern?

Hodgkin lymphoma

Which lymphoma more commonly involves tissues outside the lymph nodes early in the disease?

Non-Hodgkin lymphoma

What test measures the total number of white blood cells in the blood?

The white blood cell (WBC) count, which is part of the Complete Blood Count (CBC)

What is leukocytosis?

An abnormally elevated white blood cell count, often caused by infection, inflammation, stress, corticosteroid use, or leukemia

What is leukopenia?

An abnormally decreased white blood cell count, increasing the risk of infection

What conditions commonly cause leukopenia?

Chemotherapy, radiation therapy, bone marrow disorders, severe infections, autoimmune diseases, and certain medications

What is a WBC differential?

A laboratory test that measures the percentage of each type of white blood cell

Why is a WBC differential useful?

It helps identify the likely cause of illness by showing which type of white blood cell is increased or decreased

What does neutrophliia usually indicate?

A bacterial infection or acute inflammatory response

What does lymphocytosis usually indicate?

A viral infection

What does eosinophilia usually indicate?

A parasitic infection or an allergic disorder such as asthma

What does basophilia most commonly suggest?

An allergic response or certain myeloproliferative disorders, such as chronic myeloid leukemia (CML)