Chapter 39: Infections in Special Populations: Answered Explained

MULTIPLE CHOICE 1. The host natural defense system includes all of the following parts except: a. adaptive immune system. b. innate immune system. c. acquired immune system. d. nonspecific general barriers. ...

MULTIPLE CHOICE 1. The host natural defense system includes all of the following parts except: a. adaptive immune system. b. innate immune system. c. acquired immune system. d. nonspecific general barriers. A The various components of the immune system help control daily insults, ward off infectious diseases, or minimize the damage caused by infections. The three parts of the immune system are the nonspecific general barriers, the innate immune system, and the acquired immune system. REF: 934 OBJ: Level 1: Recall 2. What are patients called who have a serious disease and who are highly predisposed to infections by a variety of opportunistic bacterial, fungal, parasitic, and viral pathogens? a. Elderly compromised b. Immunocompromised c. Defective responders d. Extraneous responders B The term immunocompromised is used to describe patients with serious diseases who are highly predisposed to infections by a variety of opportunistic bacterial, fungal, parasitic, and viral pathogens. REF: 934 OBJ: Level 2: Interpretation 3. What is usually the leading cause of death in immunocompromised patients? a. HIV b. Hepatitis C c. Infections d. Congestive heart failure C The potential gain in years of useful life for many patients through successful management and treatment of diseases is offset by serious effects on the immune system. As a result, infection, rather than the primary illness, becomes the leading cause of death in immunocompromised patients. REF: 934 OBJ: Level 1: Recall 4. All of the following are often associated with immunosuppression except: a. HIV infection. b. acute leukemia. c. anemia. d. chemotherapy. C Immunosuppressive therapy, such as chemotherapy and radiation, frequently leads to immunocompromise. Patients with acute leukemia often have decreased white cell numbers and function. Patients with HIV also have depressed immune function. Immunosuppression may predispose patients to severe infections. REF: 934 OBJ: Level 1: Recall 5. Which of the following immune mechanisms may be decreased in patients with malignancy? a. Cell-mediated immune response b. Antibody production c. Mucous membranes barriers d. All of the above D Widespread disturbances in the humoral and cellular immune response occur in patients with malignancy. In addition, cytotoxic drugs administered to cancer patients contribute substantially to the breakdown of mucosal barriers and a decrease in cell-mediated immune reactivity in these patients. REF: 936 OBJ: Level 2: Interpretation 6. Patients with granulocyte (neutrophil) counts below _____ cells/mm3 are at a significant risk for developing an infection along with a high rate of mortality. a. 50,000 b. 10,000 c. 5,000 d. 1,000 B Once the granulocyte count drops below 500 to 1000 cells/mm3, the risk of infection increases steadily with the degree and duration of immunosuppression. In patients with a neutrophil count below 500 cells/mm3, the mortality rate may be as high as 60%. Virtually every patient whose neutrophil count is less than 100/mL for 3 weeks or more will develop an infection. The mortality rate among patients whose neutrophil count is lower than 100 cells/mm3 during the first week of infection may be as high as 80%. REF: 936 OBJ: Level 1: Recall 7. In which disease do we see a decrease in the number and function of neutrophils, including the inability to migrate to sites of inflammation, impaired phagocytosis, and reduced killing of ingested organisms, placing these patients at higher risk of infection? a. Anemia b. Hypogammaglobulinemia c. Hodgkin’s disease d. Hypergammaglobulinemia C In addition to the decrease in the number of neutrophils, inadequate neutrophil function—including the inability to migrate to sites of inflammation, impaired phagocytosis, and reduced killing of ingested organisms—predisposes patients suffering from chronic leukemia and Hodgkin’s disease to infections. REF: 936 OBJ: Level 2: Interpretation 8. What condition is most likely to occur in patients with severe neutropenia? a. Pneumonia b. Bronchitis c. Meningitis d. Septicemia D Septicemia is mostly likely to occur in patients with neutropenia because neutrophils play an important role in localizing infections. REF: 936 OBJ: Level 1: Recall 9. Patients with hematologic malignancies and those who have undergone surgery for tumors involving the head and spine may be at risk for developing: a. meningitis. b. septicemia. c. pneumonia. d. osteomyelitis. A Patients with hematologic malignancies and those who have undergone surgery for tumors involving the head and spine may suffer from central nervous system infections. Cancer patients develop meningitis infections with different organisms than patients without cancer; there are more staphylococcal infections and fewer infections with community-acquired organisms, such as Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis. REF: 936 OBJ: Level 1: Recall 10. When a child with cancer contracts cytomegalovirus (CMV), how does it manifest? a. Renal failure b. Pneumonia c. Septicemia d. Meningitis B Children with cancer are more susceptible to CMV infection than adults. The common manifestation is pneumonia, which may be unilateral or bilateral and is usually accompanied by a more severe bacterial or fungal infection. REF: 937 OBJ: Level 2: Interpretation 11. What two parasitic agents commonly affect patients with malignancy? a. Giardia lamblia and Listeria monocytogenes b. Strongyloides stercoralis and Giardia lamblia c. Pneumocystis jirovecii (carinii) and Toxoplasma gondii d. Toxoplasma gondii and Wuchereria bancrofti C Pneumocystis jirovecii (carinii) and Toxoplasma gondii are parasitic agents that commonly affect patients with malignancy because of their decreased cellular immune function. REF: 937 OBJ: Level 1: Recall 12. Cancer chemotherapy does all of the following except: a. inhibit inflammation. b. reduce capillary permeability. c. decrease cellular exudation. d. inhibit neutrophils ability to destroy bacteria. D Chemotherapy inhibits inflammation, reduces capillary permeability, and decreases cellular exudation. REF: 937 OBJ: Level 1: Recall 13. To which bacteria are people with C3 deficiency particularly susceptible? a. Staphylococcus aureus b. Toxoplasma gondii c. Listeria monocytogenes d. Streptococcus pneumoniae A Patients with C3 deficiency are particularly susceptible to sepsis with pyogenic bacteria, such as Staphylococcus aureus. REF: 937 OBJ: Level 1: Recall 14. All of the following immune defense mechanisms are depressed in burn patients except: a. humoral defense mechanisms. b. complement activity. c. cell-mediated defenses. d. IgG. B The immune defense mechanisms in burn patients, both humoral and cell-mediated, are suppressed. Immunoglobulins, especially IgG, are depressed. REF: 938 OBJ: Level 1: Recall 15. Patients who have undergone organ transplant surgery may develop opportunistic infections 1 to 6 months after surgery caused by any of the following except: a. Staphylococcus aureus. b. varicella-zoster virus. c. influenzae virus. d. hepatitis virus. A During the first month after transplantation, postoperative bacterial infections are most common. One to 6 months after transplantation, opportunistic infections caused by cytomegalovirus (CMV), Mycobacterium tuberculosis, Listeria monocytogenes, Nocardia spp., Aspergillus spp., Pneumocystis carinii, Epstein-Barr virus, varicella-zoster virus, and hepatitis virus are most likely to be reported. REF: 938 OBJ: Level 1: Recall 16. Postsplenectomy patients are more susceptible to infections with all the following agents except: a. Streptococcus pneumoniae. b. Haemophilus influenzae. c. Neisseria meningitidis. d. Staphylococcus aureus. D The major risk following splenectomy is overwhelming bacterial infection or postsplenectomy sepsis. This condition results in the body’s decreased ability to clear bacteria from the blood system, as well as lowered levels of a protein in blood plasma that helps fight viruses. The loss of splenic function puts patients at risk of infection, such as S. pneumoniae, H. influenzae, N. meningitidis, and malaria. REF: 938 OBJ: Level 1: Recall 17. All of the following factors contribute to an increased risk of infection except: a. low leukocyte numbers. b. decrease in cellular immune function. c. splenectomy. d. high levels of immunoglobulins. D The primary predisposing factor in these patient populations is the presence of underlying disease that affects host defense mechanisms. Examples of compromised defense mechanisms include leukocyte number or function, humoral and cell-mediated immune functions, and reticuloendothelial system function. REF: 934 OBJ: Level 2: Interpretation 18. Organisms that are commonly associated with ventilator-associated pneumonia include: a. Pseudomonas aeruginosa. b. Streptococcus pyogenes. c. Mycobacterium tuberculosis. d. Clostridium difficile. A Organisms associated with VAP include S. pneumoniae, H. influenzae, S. aureus, P. aeruginosa, Klebsiella, Enterobacter, Serratia, Acinetobacter, Stenotrophomonas, and B. cepacia. REF: 936 OBJ: Level 1: Recall 19. Which organism accounts for up to 45% of interstitial pneumonia cases in cancer patients? a. Pseudomonas aeruginosa b. Staphylococcus aureus c. Pneumocystis jirovecii d. Streptococcus pneumoniae C Pneumocystis jirovecii accounts for as many as 45% of cases of interstitial pneumonia in cancer patients. REF: 937 OBJ: Level 1: Recall 20. The primary cause of immunodeficiency in patients with acquired immunodeficiency syndrome (AIDS) due to HIV is because of the virus’ focused attack on which of the following cell types? a. Granulocytes b. Helper T cells c. Macrophages d. Stem cells D Acquired immune deficiency syndrome (AIDS) is caused by HIV, a virus that infects and destroys CD4+ helper T cells. The helper T cells are critical for stimulating B cells to produce antibody, cytotoxic T cells to lyse target cells, and macrophages to phagocytize and destroy ingested organisms. Because of the integral role for this cell type in almost every arm of the immune response, the lack of this cell causes a profound immunosuppression that seriously undermines the body’s ability to defend itself from infection and disease. REF: 937 OBJ: Level 2: Interpretation