Pathophysiology Ch. 8 Infection and Defects in Mechanisms of Defense

A 30-year-old female is diagnosed with systemic lupus erythematosus (SLE). Which symptoms are a result of a type II hypersensitivity? a. Anemia b. Seizures c. Lymphopenia d. Facial rash e. Photosensitivity

ANS: A, C a. Anemia c. Lymphopenia The patient is experiencing type II hypersensitivity when experiencing anemia and lymphopenia. Seizures, facial rash, and photosensitivity are not associated with type II hypersensitivity reactions. REF:p. 208

A 22-year-old was recently diagnosed with acquired immunodeficiency syndrome (AIDS). Which decreased lab finding would be expected to accompany this virus? a. CD4+ T-helper b. CD8 T-helper c. CDC cells d. CDC10 cells

a. CD4+ T-helper The major immunologic finding in AIDS is the striking decrease in the number of CD4+ T cells. The change occurs in CD4 cells, not CD8. Neither CDC nor CDC 10 is a type of cell. REF: p. 194

A person is given an attenuated antigen as a vaccine. When the person asks what was given in the vaccine, how should the nurse respond? The antigen is: a. alive, but less infectious. b. mutated, but highly infectious. c. normal, but not infectious. d. inactive, but infectious.

a. alive, but less infectious. Attenuated vaccines are alive, but less infectious. Attenuated vaccines are not mutated or highly infectious. Inactive infers the virus is killed. REF: p. 188

When a nurse cares for a patient with systemic lupus erythematosus (SLE), the nurse remembers this disease is an example of: a. autoimmunity. b. alloimmunity. c. homoimmunity. d. alleimmunity.

a. autoimmunity. SLE is the most common, complex, and serious of the autoimmune disorders. SLE is not identified as alloimmune, homoimmune, or alleimmune. REF: p. 208

An immunologist is discussing endotoxin production. Which information should the immunologist include? Endotoxins are produced by: a. gram-negative bacteria. b. gram-positive bacteria. c. gram-negative fungi. d. gram-positive fungi.

a. gram-negative bacteria. Endotoxins are produced by gram-negative bacteria. They are not produced by gram-positive bacteria or any type of fungi. REF: p. 181

A 30-year-old female complains of fatigue, arthritis, rash, and changes in urine color. Laboratory testing reveals anemia, lymphopenia, and kidney inflammation. Assuming a diagnosis of SLE, which of the following is also likely to be present? a. Anti-LE antibodies b. Autoantibodies c. Antiherpes antibodies d. Anti-CMV antibodies

b. Autoantibodies The presence of autoantibodies is a diagnostic criterion for SLE. Diagnostic criterion for SLE would include positive LE. Neither antiherpes nor anti-CMV antibodies are associated with a diagnosis SLE. REF: p. 208

A 5-year-old male becomes ill with a severe cough. Histologic examination reveals a bacterial infection, and further laboratory testing reveals cell membrane damage and decreased protein synthesis. Which of the following is the most likely cause of this illness? a. Endotoxin b. Exotoxin c. Hemolysis d. Septicemia

b. Exotoxin Exotoxins are enzymes that can damage the plasma membranes of host cells or can inactivate enzymes critical to protein synthesis, and endotoxins activate the inflammatory response and produce fever. Endotoxins released by blood-borne bacteria cause the release of vasoactive enzymes that increase the permeability of blood vessels. Hemolysis is the breakdown of red cells. Septicemia is the growth of bacteria in the blood. REF: p. 180

Which of the following is a characteristic of the human immunodeficiency virus (HIV), which causes AIDS? a. HIV only infects B cells. b. HIV is a retrovirus. c. Infection does not require a host cell receptor. d. After infection, cell death is immediate.

b. HIV is a retrovirus. AIDS is an acquired dysfunction of the immune system caused by a retrovirus (HIV) that infects and destroys CD4+ lymphocytes (T-helper cells). HIV infection begins when a virion binds to CD4, not a B cell. Infection requires a host cell receptor. The cell remains dormant but does not die. REF: p. 194

What common symptom should be assessed in individuals with immunodeficiency? a. Anemia b. Recurrent infections c. Hypersensitivity d. Autoantibody production

b. Recurrent infections The clinical hallmark of immunodeficiency is a propensity to unusual or recurrent severe infections. The type of infection usually reflects the immune system defect. Neither anemia, autoantibody production, nor hypersensitivity is a manifestation of immunodeficiency. REF: p. 189

In addition to matching ABO antigens, a blood transfusion must also be matched for: a. HLA type. b. Rh antigen. c. immunoglobulins. d. platelet compatibility.

b. Rh antigen. Blood transfusions must also be matched for the Rh antigen. Blood transfusions do not need to be matched to HLA, immunoglobulins, or platelet compatibility. REF: p. 209

A 5-year-old male presents with low-set ears, a fish-shaped mouth, and involuntary rapid muscular contraction. Laboratory testing reveals decreased calcium levels. Which of the following diagnosis is most likely? a. B-lymphocyte deficiency b. T-lymphocyte deficiency c. Combined immunologic deficiency d. Complement deficiency

b. T-lymphocyte deficiency DiGeorge syndrome results in greatly decreased T cell numbers and function and is evidenced by abnormal development of facial features that are controlled by the same embryonic pouches; these include low-set ears, fish-shaped mouth, and other altered features. B-lymphocyte deficiency is not manifested by these symptoms. Neither combined immunologic deficiency nor complement deficiency is manifested by these symptoms. REF: p. 191

Which information indicates a correct understanding of viral vaccines? Most viral vaccines contain: a. active viruses. b. attenuated viruses. c. killed viruses. d. viral toxins.

b. attenuated viruses. Viral vaccines contain live viruses that are weakened (attenuated). Viral vaccines do not contain active viruses, killed viruses, or toxins. REF: p. 188

When a nurse notices that a patient has type O blood, the nurse realizes that anti-_____ antibodies are present in the patient's body. a. A only b. B only c. A and B d. O

c. A and B Type O individuals have both anti-A and anti-B antibodies but not O. REF: p. 209

When the maternal immune system becomes sensitized against antigens expressed by the fetus, what type of immune reaction occurs? a. Autoimmune b. Anaphylaxis c. Alloimmune d. Allergic

c. Alloimmune Alloimmunity can be observed during immunologic reactions against transfusions, transplanted tissue, or the fetus during pregnancy. Autoimmunity is a disturbance in the immunologic tolerance of self-antigens. The most rapid and severe immediate hypersensitivity reaction is anaphylaxis. An allergic response occurs related to exposure to an allergen. REF: p. 199

When the immunologist says that pathogens possess virulence, what does virulence mean? a. Spreads from one individual to others and causes disease. b. Induces an immune response. c. Causes disease. d. Damages tissue.

c. Causes disease. Virulence is the capacity of a pathogen to cause severe disease—for example, measles virus is of low virulence; rabies virus is highly virulent. Communication is the ability to spread from one individual to others and cause disease. Immunogenicity is the ability of pathogens to induce an immune response. Damaging tissues is the pathogen's mechanism of action. REF: p. 177

A 50-year-old female experiences decreased blood pressure, decreased oxygen delivery, cardiovascular shock, and subsequent death. A complication of endotoxic shock is suspected. Which of the following is the most likely cause? a. Gram-positive bacteria b. Fungi c. Gram-negative bacteria d. Virus

c. Gram-negative bacteria Symptoms of gram-negative septic shock are produced by endotoxins. Once in the blood, endotoxins cause the release of vasoactive peptides and cytokines that affect blood vessels, producing vasodilation, which reduces blood pressure, causes decreased oxygen delivery, and produces subsequent cardiovascular shock. Gram-positive bacteria nor fungi do not produce endotoxins and thus do not manifest in shock. Viruses do not produce symptoms of shock. REF: pp. 181-182

An infant is experiencing hemolytic disease of the newborn. Which of the following would the nurse expect to find in the infant's history and physical? a. The mother was exposed to measles. b. The father was exposed to Agent Orange. c. The baby is Rh positive. d. The baby was born 6 weeks prematurely.

c. The baby is Rh positive. Hemolytic disease of the newborn was most commonly caused by IgG anti-D alloantibody produced by Rh-negative mothers against erythrocytes of their Rh-positive fetuses. This disorder is not due to the mother's exposure to measles, the father's exposure to Agent Orange, or the baby's prematurity. REF: p. 209

When a patient asks the nurse what hypersensitivity is, how should the nurse respond? Hypersensitivity is best defined as: a. a reduced immune response found in most pathologic states. b. a normal immune response to an infectious agent. c. an excessive or inappropriate response of the immune system to a sensitizing antigen. d. antigenic desensitization.

c. an excessive or inappropriate response of the immune system to a sensitizing antigen. Hypersensitivity is an altered immunologic response to an antigen that results in disease or damage to the individual. It is not a reduced immune response or a response to an infectious agent. Antigenic desensitization is performed to decrease hypersensitivity. REF: p. 199

A 10-year-old male is stung by a bee while playing in the yard. He begins itching and develops pain, swelling, redness, and respiratory difficulties. He is suffering from: a. immunodeficiency. b. autoimmunity. c. anaphylaxis. d. tissue-specific hypersensitivity.

c. anaphylaxis. Anaphylaxis occurs within minutes of reexposure to the antigen and can be either systemic (generalized) or cutaneous (localized). Immunodeficiency is a decrease in the immune response. Autoimmunity is a disturbance in the immunologic tolerance of self-antigens. Tissue-specific reaction is an autoimmune reaction. REF: p. 201

When a patient presents at the emergency department for an allergic reaction, the nurse recognizes the most severe consequence of a type I hypersensitivity reaction is: a. urticaria. b. hives. c. anaphylaxis. d. antibody-dependent cell-mediated cytotoxicity (ADCC).

c. anaphylaxis. The most rapid and severe immediate hypersensitivity type I reaction is anaphylaxis. Urticaria, or hives, is a dermal (skin) manifestation of allergic reactions. Hives and urticaria are similar responses. ADCC is a mechanism that involves natural killer (NK) cells. Antibodies on the target cell are recognized by Fc receptors on the NK cells, which release toxic substances that destroy the target cell. REF: p. 201

Which information indicates a good understanding of bacterial vaccines? Most bacterial vaccines contain: a. fully active bacteria. b. synthetic bacteria. c. dead bacteria. d. bacterial toxins.

c. dead bacteria. Vaccines are biological preparations of weakened or dead pathogens that when administered stimulate production of antibodies or cellular immunity against the pathogen without causing disease. Vaccines are not fully active bacteria, nor are they synthetic or toxins. REF: p. 188

A patient presents with poison ivy on the extremities, face, and buttocks after an initial exposure 48 hours ago. This condition is an example of: a. anaphylaxis. b. serum sickness. c. delayed hypersensitivity. d. viral disease.

c. delayed hypersensitivity. The response to poison ivy is a delayed hypersensitivity because it takes up to 72 hours to develop. Anaphylaxis is immediate. Serum sickness-type reactions are caused by the formation of immune complexes in the blood and their subsequent generalized deposition in target tissues. Poison ivy is not a viral disease. REF: p. 201

When the immunologist says that pathogens possess infectivity, what is the immunologist explaining? Infectivity allows pathogens to: a. spread from one individual to others and cause disease. b. induce an immune response. c. invade and multiply in the host. d. damage tissue.

c. invade and multiply in the host. Infectivity is the ability of the pathogen to invade and multiply in the host. Communication is the ability to spread from one individual to others and cause disease. Immunogenicity is the ability of pathogens to induce an immune response. Damaging tissues is the pathogen's mechanism of action. REF: p. 177

After studying about viruses, which information indicates the student has a good understanding of viruses? Viruses: a. contain no DNA or RNA. b. are capable of independent reproduction. c. replicate their genetic material inside host cells. d. are easily killed by antimicrobials.

c. replicate their genetic material inside host cells. Virus replication depends totally on the ability of the virus to infect a permissive host cell, a cell that cannot resist viral invasion and replication. Viruses contain both DNA and RNA, are incapable of independent reproduction, and cannot be killed by antimicrobials. REF: pp. 182-183

A nurse recalls that an example of an immune-complex-mediated disease is: a. bronchial asthma. b. contact dermatitis. c. serum sickness. d. rheumatoid arthritis.

c. serum sickness. Immune-complex disease can be a systemic reaction, such as serum sickness, and related to type III reactions. Bronchial asthma is not an immune-complex-mediated disease and is related to type I reactions. Neither contact dermatitis nor rheumatoid arthritis is related to type III reactions. REF: p. 205

What is the chance that two siblings share both HLA haplotypes, making them a good match for an organ transplant from one to the other? a. 100% b. 75% c. 50% d. 25%

d. 25% Odds dictate that children will share one haplotype with half their siblings and either no haplotypes or both haplotypes with a quarter of their siblings. Thus, the chance of finding a match among siblings is much higher (25%) than the general population. REF: p. 210

A 15-year-old male suffers from severe hemorrhage following a motor vehicle accident. He is given a blood transfusion, but shortly afterward the red blood cells are destroyed by agglutination and lysis. Which of the following blood type transfusion type matches would cause this? a. A-A b. B-O c. AB-O d. A-AB

d. A-AB A person with type A blood also has circulating antibodies to the B carbohydrate antigen. If this person receives blood from a type AB or B individual, a severe transfusion reaction occurs, and the transfused erythrocytes are destroyed by agglutination or complement-mediated lysis. Type A can receive type A blood. Type B and type AB can receive type O. REF: p. 209

A 30-year-old male was diagnosed with HIV. Which of the following treatments would be most effective? a. Reverse transcriptase inhibitors b. Protease inhibitors c. Entrance inhibitors d. Antiretroviral therapy (ART)

d. Antiretroviral therapy (ART) The current regimen for treatment of HIV infection is a combination of drugs, termed antiretroviral therapy (ART). The remaining options are individual components of the ART treatment format. REF: p. 197

A 30-year-old male is having difficulty breathing and has been spitting blood. He reports that he began experiencing this reaction after cleaning his pigeons' cages. Testing reveals he is suffering from allergic alveolitis. Which of the following is he experiencing? a. Serum sickness b. Raynaud phenomenon c. Antibody-dependent cytotoxicity d. Arthus reaction

d. Arthus reaction The Arthus reaction is a model of localized or cutaneous reactions. Serum sickness-type reactions are caused by the formation of immune complexes in the blood and their subsequent generalized deposition in target tissues. Typically affected tissues are the blood vessels, joints, and kidneys. Raynaud phenomenon is a condition caused by the temperature-dependent deposition of immune complexes in the capillary beds of the peripheral circulation. Antibody-dependent cytotoxicity is a type II form. REF: pp. 205-206

Which information would indicate more teaching is needed regarding hypersensitivity reactions? Type _______ hypersensitivity reactions involve an antibody response. a. I b. II c. III d. IV

d. IV Type IV reactions are mediated by T lymphocytes and do not involve antibodies. All the remaining options are associated with antibody responses. REF: p. 206

A 40-year-old female is diagnosed with SLE. Which of the following findings would be considered a symptom of this disease? a. Gastrointestinal ulcers b. Decreased glomerular filtration rate c. Rash on trunk and extremities d. Photosensitivity

d. Photosensitivity Photosensitivity is one of the 11 common clinical findings in SLE. Gastrointestinal ulcers are not a finding in SLE. Proteinuria is a symptom of SLE. A rash on the face is a symptom, but not a rash on the body. REF: p. 208

After studying about fungi, which information indicates a correct understanding of fungi? Fungi causing deep or systemic infections: a. are easily treated with penicillin. b. are extremely rare. c. never occur with other infections. d. are commonly opportunistic.

d. are commonly opportunistic. Diseases caused by fungi are called mycoses. Mycoses are common and can be opportunistic and occur with other infections but are not treatable with penicillin. REF: p. 184

The nurse would correctly respond that the etiology of a congenital immune deficiency is due to a(n): a. negative response to an immunization. b. adverse response to a medication. c. renal failure. d. genetic defect.

d. genetic defect. A primary (congenital) immune deficiency is caused by a genetic defect. A primary (congenital) immune deficiency is not a response to an immunization, an adverse response to a medication, or due to renal failure. REF: p. 189

A nurse recalls bacteria become resistant to antimicrobials by: a. proliferation. b. attenuation. c. specialization. d. mutation.

d. mutation. Antibiotic resistance is usually a result of genetic mutations that can be transmitted directly to neighboring microorganisms by plasmid exchange. Antibiotic resistance is not a result of proliferation, attenuation, or specialization. REF: p. 188