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Chapter 33
Immunologic
Disorders
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Anatomy and Physiology of the
Immune System
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Anatomic Structures and Components
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Bone marrow
Lymph, lymphatics, and lymph nodes
Spleen
Thymus
Stem cells
White blood cells (leukocytes)
• Neutrophils, monocytes and macrophages, eosinophils,
basophils, mast cells, B lymphocytes (B cells), T lymphocytes
(T cells)
• Cytokines
• Eicosanoids
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Figure 33-1
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Physiologic Functions: Innate
Immunity
• Operational at all times, whether or not a
pathogen is present
• At birth, are immediately functional
• Include anatomic and physiologic barriers,
inflammatory response, and the ability of
certain cells to phagocytose foreign invaders
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Physiologic Functions: Barriers
• Skin and mucous membranes: a protective covering;
secretes substances that inhibit pathogen growth
• Sweat glands secrete lysozyme, antimicrobial enzyme
• Acidic GI and GU systems inhibit growth of pathogenic
organisms
• Secretions from the respiratory and gastrointestinal tracts
contain the antibody IgA, as well as phagocytes
• Surfaces colonized by normal bacterial flora; prevents
pathogens from attaching/gaining access to the body
• Coughing and sneezing, peristalsis in the GI tract, emptying
the bladder, and sloughing of dead skin cells: remove
microorganisms from the body, thus preventing their invasion
and overgrowth
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Physiologic Functions: Inflammation
• Body initially responds to an injury or infection
by dilating the capillary bed and increasing the
capillary permeability of the affected area
• Brings white blood cells to the site; allows them
to enter the tissue to attack microorganisms
• This multistep process is called inflammation
and is recognized by rubor (redness), tumor
(swelling), calor (heat), and dolor (pain) at the
site of injury or infection
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Physiologic Functions: Phagocytosis
• The process of ingesting and digesting
invading pathogens, dead cells, and cellular
debris
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Physiologic Functions:
Acquired Immunity
• Specific to particular pathogen: activated only
when needed
• Antibody mediated
• Initiated when IgM immunoglobulins on B
lymphocytes detect a foreign antigen
• Active: person synthesizes own antibodies in
response to pathogen
• Passive: antibody produced by person or animal is
transferred to another person
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Physiologic Functions:
Acquired Immunity
• Cell mediated
• Aimed at intracellular defects caused by viruses and
cancer
• Responsible for delayed hypersensitivity reactions
and rejection of transplanted tissue
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Figure 33-2
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Physiologic Functions: Tolerance
• Immune system must recognize its own proteins
• Autoimmune diseases occur when there is a
breakdown of tolerance; immune system identifies its
own proteins as foreign and mounts a response to
destroy these self-proteins
• Examples: idiopathic thrombocytopenic purpura (ITP),
thrombotic thrombocytopenic purpura (TTP), acute
rheumatic fever, type 1 diabetes mellitus, systemic
lupus erythematosus, rheumatoid arthritis, Graves’
disease, and Hashimoto’s thyroiditis
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Age-Related Changes
• Bone marrow becomes less productive
• Lymphatic tissue shrinks, resulting in fewer and
smaller lymph nodes
• Immunologic function not affected unless a
person is unusually stressed by trauma, a
chronic infection, or treatment for cancer
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Nursing Assessment of the
Immune System
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Chief Complaint and History of
Present Illness
• Frequent or persistent infections, bleeds for a
long time when cut, bruises easily, or has
chronic fatigue
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Past Medical History
• Cancer or prior treatment for cancer, HIV
infection, history of splenectomy, or an
indwelling venous access device, indicating
that the patient needed long-term venous
access
• Medications patient is using or a recent change
in medication may suggest an underlying
immunologic problem
• Ask about recent changes in medications and
recent immunizations
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Family History
• Note family history of immunologic disorders
such as cancer
• Death of a family member at a young age for
reasons other than trauma may indicate a
genetic immunologic disorder
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Review of Systems
• Reddened, swollen, painful, warm areas
• Ask about fever, chills, or night sweats
• Breaks in the skin, ulcers, lesions, or enlarged
lymph nodes
• Assess for weakness, lethargy, malaise,
restlessness, apprehension, or headache
• Ask about sinus pain, dyspnea, or cough
• Pain or burning with urination
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Functional Assessment
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Occupation and hobbies
Self-concept
Activity and exercise
Sleep and rest
Nutrition
Interpersonal relationships
Coping and stress
Perception of health
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Physical Examination
• General survey
• Responsiveness, mood, expression, posture
• Carefully inspect and describe reddened, swollen,
or painful areas
• Skin
• Note general color, texture, turgor, temperature, and
integrity of the skin
• Palpate for swollen or painful areas
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Physical Examination
• Head and neck
• Enlarged, swollen, or draining areas
• Thorax
• The examiner with advanced skills may palpate the
axilla for enlarged lymph nodes
• Lungs
• Document respiratory rate and effort; auscultate for
wheezing, crackles, or rhonchi
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Physical Examination
• Heart and vascular system
• Heart rate and blood pressure
• Abdomen
• The examiner with advanced skills may palpate the
abdomen for tenderness
• Palpate the groin for enlarged lymph nodes
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Diagnostic Tests and Procedures
• Blood tests
• Complete blood cell (CBC) count
• Antinuclear antibody test
• Enzyme-linked immunosorbent assay and Western
blot tests
• Cultures of blood, urine, sputum, and stool
• Detect infections in blood, sputum, urine, stool
• Skin tests
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Nursing Actions for the Patient at
Risk for Injury from Infection
• The lower a patient’s white blood cell count, in
particular the lower the neutrophil count, the
greater the patient’s risk of infection
• See Box 33-2, p. 599
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Bone Marrow Transplant and
Peripheral Blood Stem Cell Transplant
• Restore hematologic and immunologic systems
in patients with malignancies who have
received extremely high doses of
chemotherapy and radiation therapy
• Allogeneic bone marrow transplant
• Autologous bone marrow transplant
• Peripheral blood stem cell transplant
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White Blood Cell Disorders of the
Immune System: Neutropenia
• Total number of neutrophils abnormally low,
increasing risk of infection
• Caused by decreased bone marrow
production, chemotherapy, radiation therapy,
certain drugs or an autoimmune reaction
• Also by increased neutrophil utilization
because of overwhelming infection
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White Blood Cell Disorders of the
Immune System: Neutropenia
• Common sites of infection: lung, blood, skin,
urinary tract, gastrointestinal tract
• Goal of antibiotic therapy: support patient until
patient’s own white blood cells are available to
fight the infection
• Important to minimize patient’s exposure to
infectious agents by instituting compromised
host precautions
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Leukemia
• Cancer of the white blood cells: bone marrow
produces too many immature white blood cells
• Immature white blood cells leave patient at
great risk for life-threatening infections
• Factors: exposure to large doses of ionizing
radiation or exposure to certain chemicals such
as benzene, a compound found in gasoline
• Two main types—myelogenous and
lymphocytic
• Each type can be either chronic or acute
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Leukemia
• Signs and symptoms of acute leukemia
• Fevers and night sweats
• Fatigue, paleness, tachycardia, and tachypnea
• Petechiae or purpura, epistaxis, gingival bleeding,
melena, or menorrhagia
• Weight loss and swollen lymph nodes
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Leukemia
• Medical diagnosis of acute leukemia
• CBC with extremely high white blood cell count
• Bone marrow biopsy
• Medical treatment of acute leukemia
• Chemotherapy
• Antibiotics and blood transfusions
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Leukemia
• Assessment
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Signs or symptoms of infection
Complete vital signs every 4 hours
If sputum, note the amount and color
Skin for reddened, swollen, painful, or draining
areas
Inspect the mouth and pharynx for reddened,
swollen, painful, or draining areas
Assess for any evidence of bleeding
Petechiae, purpura, or ecchymoses
Perform a guaiac test
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Leukemia
• Interventions
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Risk for Injury
Fatigue
Impaired Oral Mucous Membranes
Imbalanced Nutrition: Less Than Body
Requirements
• Anxiety
• Ineffective Therapeutic Regimen Management
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Hypersensitivity Reactions
• Exaggerated immune responses that can be
uncomfortable and harmful to the patient
• Four types of hypersensitivity reactions,
classified according to the time between
exposure and reaction, immune mechanism
involved, and site of reaction
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Hypersensitivity Reactions
• Type I
• Immediate hypersensitivity reactions are mediated
by IgE reacting to common allergens, such as dust,
pollen, animal dander, insect stings, or various
drugs
• Either local, resulting in local swelling and
discomfort, or systemic, resulting in anaphylaxis and
possible death if not recognized and treated
promptly
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Hypersensitivity Reactions
• Type II
• Immediate hypersensitivity reactions are mediated
by antibody reactions
• Can occur with a mismatched blood transfusion or
as response to various drugs
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Hypersensitivity Reactions
• Type III
• Immediate hypersensitivity reactions result in tissue
damage resulting from precipitation of antigenantibody immune complexes
• Can occur with autoimmune reactions, some
occupational diseases, or as response to various
drugs
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Hypersensitivity Reactions
• Type IV
• Delayed hypersensitivity reactions result from
immune cells migrating to the site of exposure days
after the exposure to the antigen
• Can occur with contact dermatitis, measles rash,
tuberculin skin testing, or various drugs
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Idiopathic Thrombocytopenic
Purpura (ITP)
• IgG mistakenly helps destroy patient’s platelets
• Drugs that induce ITP: sulfonamides, thiazide
diuretics, chlorpropamide, quinidine, and gold.
Patients with HIV are at increased risk for
developing ITP
• Treatment: steroids and intravenous immune
globulin (IVIG)
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Thrombotic Thrombocytopenic
Purpura (TTP)
• Exaggerated immunologic response to vessel
injury that results in extensive clot formation
and decreased blood flow to the site
• Patients critically ill; develop fever,
thrombocytopenia, hemolytic anemia, renal
impairment, and neurologic symptoms
• The main treatment is plasmapheresis
• Others: steroids, antiplatelet agents (e.g.,
aspirin, dipyridamole, Persantine),
splenectomy, or all three
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Systemic Lupus Erythematosus
• Autoimmune disease: immune system unable to
recognize itself; mounts an immune response against
its own proteins
• Damage from antibodies and immune complexes
directed against one/many organs
• The cause is unknown
• Cause of death: infection and disease of the
cardiovascular, renal, pulmonary, and central nervous
systems
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Systemic Lupus Erythematosus
• Signs and symptoms
• Fatigue, malaise, fever, anorexia, nausea, and
weight loss
• Arthralgias and myalgias
• Joints often swollen, tender, stiff, and painful
• Rash and photosensitivity
• Butterfly-shaped rash across the bridge of the nose and the
cheeks
• Inflammation of the retina can result in suddenonset blindness
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Systemic Lupus Erythematosus
• Diagnosis
• No one test confirms the diagnosis of SLE
• Based on constellation of symptoms
• If any four of the following symptoms: SLE
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Characteristic rash
Photosensitivity with exposure to sunlight
Oral ulcers
Arthritis
Pleuritis or pericarditis
Renal, neurologic, hematologic, or immunologic disorder
Positive ANA
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Systemic Lupus Erythematosus
• Medical treatment
• There is no cure
• Treatment: symptomatic and aimed at minimizing
symptoms, preventing organ damage, and
maintaining quality of life
• Analgesics, nonsteroidal anti-inflammatory drugs
(NSAIDs), antimalarials, corticosteroids
• Cytotoxic agents suppress the abnormal immune
response
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Systemic Lupus Erythematosus
• Assessment
• Thorough health history and physical examination
• Complete functional assessment: determine the
effects of the symptoms on the activities of daily
living
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Systemic Lupus Erythematosus
• Interventions
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Fatigue
Acute Pain
Disturbed Body Image
Ineffective Coping
Ineffective Therapeutic Regimen Management
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Human Immunodeficiency Virus (HIV)
• A retrovirus that infects cells expressing CD4
on their cell membranes, primarily TH cells
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Transplant Rejection
• Patients who undergo kidney, heart, liver, or
other organ transplantation risk that their
healthy immune system will recognize the
transplanted organ as foreign and try to
destroy it
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Transplant Rejection
• Rejections occur because
• T lymphocytes can directly attack the allograft,
resulting in acute transplant rejection within hours of
the transplant
• B lymphocytes can make antibodies against the
allograft
• Fibrin accumulates on the transplanted tissue,
causing ischemia
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Transplant Rejection
• Donor-recipient tissue matching minimizes
recipient’s immune system attacking allograft
• Drug combinations suppress recipient’s
immune system and minimize the immune
response to the allograft
• Drugs suppress the patient’s ability to fight
bacteria, viruses, fungi, and parasites, putting
at risk for infection
• Combinations of the steroids cyclosporine and
azathioprine chronically suppress the immune
system after an organ transplant
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Transplant Rejection
• Several newer drugs target the T cells while
preserving B cell function and thus more of the
patient’s immune function
• Tacrolimus (Prograf), antilymphocyte globulin,
antithymocyte globulin, and murine monoclonal
antibody to CD3 (OKT3)
• Patients who have undergone organ
transplantation must take immunosuppressive
therapy the rest of their lives to preserve the
allograft
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