1elsevier items and derived items © 2007 by saunders, an imprint of elsevier, inc. chapter 33...

1Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.

Chapter 33

Immunologic Disorders


Learning Objectives

• List the components of the immune system and describe• their role in innate immunity, acquired immunity, and tolerance.• List the data to be collected when assessing a patient

with a disorder of the immune system.• Describe the tests and procedures used to diagnose disorders

of the immune system and nursing considerations for each.• Describe the nursing care for patients undergoing common

therapeutic measures for disorders of the immune system.• Describe the pathophysiology, signs and symptoms,

medical diagnosis, and medical treatment for selecteddisorders of the immune system.

• Assist in developing a nursing care plan for a patient witha disorder of the immune system.


Anatomy and Physiology of the Immune System


Anatomic Structures and Components

• 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


Figure 33-1


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


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


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


Physiologic Functions: Phagocytosis

• The process of ingesting and digesting invading pathogens, dead cells, and cellular debris


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


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


Figure 33-2


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


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


Nursing Assessment of the Immune System


Chief Complaint and History of Present Illness

• Frequent or persistent infections, bleeds for a long time when cut, bruises easily, or has chronic fatigue


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


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


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


Functional Assessment

• Occupation and hobbies• Self-concept• Activity and exercise • Sleep and rest • Nutrition • Interpersonal relationships • Coping and stress • Perception of health


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



• 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



• 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


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


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


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


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


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


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


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


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


Leukemia

• Assessment• 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


Leukemia

• Interventions• Risk for Injury • Fatigue• Impaired Oral Mucous Membranes • Imbalanced Nutrition: Less Than Body

Requirements • Anxiety • Ineffective Therapeutic Regimen Management


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



• 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



• Type II • Immediate hypersensitivity reactions are mediated

by antibody reactions• Can occur with a mismatched blood transfusion or

as response to various drugs



• Type III • Immediate hypersensitivity reactions result in tissue

damage resulting from precipitation of antigen-antibody immune complexes

• Can occur with autoimmune reactions, some occupational diseases, or as response to various drugs



• 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


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)


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


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



• 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 sudden-onset blindness



• Diagnosis

• No one test confirms the diagnosis of SLE• Based on constellation of symptoms• If any four of the following symptoms: SLE

• Characteristic rash • Photosensitivity with exposure to sunlight • Oral ulcers • Arthritis • Pleuritis or pericarditis • Renal, neurologic, hematologic, or immunologic disorder • Positive ANA



• 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



• Assessment• Thorough health history and physical examination• Complete functional assessment: determine the

effects of the symptoms on the activities of daily living



• Interventions• Fatigue• Acute Pain• Disturbed Body Image • Ineffective Coping • Ineffective Therapeutic Regimen Management


Human Immunodeficiency Virus (HIV)

• A retrovirus that infects cells expressing CD4 on their cell membranes, primarily TH cells


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



• 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



• 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



• 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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