NUR 426 Patho_Exam_2_question and answers

h. 12 – Mechanisms of Infectious Disease 1. Staphylococcus aureus commonly found in the skin, nares, and other body sites of patients without any signs and symptoms of infection is known as which of the following conditions listed below? A) An opportunistic infection B) A parasitic infestation C) Bacterial colonization D) A saprophytic infection Ans: C Feedback: The ongoing presence of bacteria in the body that do not cause infection is called colonization. Opportunistic infection by ordinarily nonpathogenic organisms can occur in immunosuppressed hosts. Parasitism is a condition in which the organism exists at the expense of, and without benefiting, the host. Saprophytes do not cause infection. 2. Which of the following statements is an accurate descriptor of the role of viruses in human infections? A) Viruses have no genetic material of their own. B) Some viruses are capable of transforming normal host cells into malignant cells. C) Viruses are often implicated in cases of transmissible neurodegenerative diseases. D) Viruses require stimulation after a latent period before they are able to produce symptoms. Ans: B Feedback: Viruses that are categorized as oncogenic are able to induce malignancy in host cells. Viruses have limited genetic material (either RNA or DNA), but no virus lacks genetic material. Transmissible neurodegenerative disease is associated with prions. Not all viruses include a latent period. 3. Which of the following types of pneumonia listed below is best characterized by an infective agent that produces sputum samples with a peptidoglycan cell wall, expresses endotoxins, replicates readily in broth and on agar, grows in clusters, has pili, and does not stain when exposed to crystal violet? A) Chlamydial B) Viral C) Mycoplasmal D) Bacterial Ans: D Feedback: Although chlamydiae, viruses, and mycoplasmas all can cause pneumonia, only bacteria have all of these characteristics. Chlamydiae and viruses are obligate intracellular organisms and therefore would grow only in cell culture, and mycoplasmas lack the peptidoglycan cell wall typical of bacteria. 4. The nurse will most likely assess which of the following clinical manifestations in a client who was diagnosed with Creutzfeldt-Jakob disease?