ATI RN
ATI Pathophysiology
1. A patient has been diagnosed with cytomegalovirus (CMV). Which of the following drugs would be ineffective in the treatment of this disease?
- A. Ribavirin (Rebetol)
- B. Ganciclovir (Cytovene) IV
- C. Foscarnet (Foscavir) IV
- D. Valganciclovir hydrochloride (Valcyte)
Correct answer: A
Rationale: The correct answer is A, Ribavirin (Rebetol). Ribavirin is not effective against CMV. Choice B, Ganciclovir (Cytovene) IV, is a common treatment for CMV as it inhibits viral DNA synthesis. Choice C, Foscarnet (Foscavir) IV, is also used for CMV infections by blocking viral DNA polymerase. Choice D, Valganciclovir hydrochloride (Valcyte), is a prodrug of Ganciclovir and is effective against CMV. Therefore, Ribavirin is the drug that would be ineffective in treating CMV.
2. Which immunoglobulin presents the first challenge to the antigen?
- A. IgA
- B. IgG
- C. IgM
- D. IgE
Correct answer: C
Rationale: IgM is the first immunoglobulin to challenge the antigen during an immune response. IgM is the primary antibody produced during the initial or primary immune response. It is efficient in agglutination and complement activation, making it crucial in the early stages of defense. IgA is mainly found in mucosal areas and secretions. IgG is the most abundant antibody in circulation and is involved in secondary immune responses. IgE is primarily associated with allergic reactions and parasitic infections. Therefore, IgM is the correct choice as it acts first during the immune response, while the other immunoglobulins have different roles and functions.
3. A patient was sneezing frequently after a few days of allergic rhinitis, and she noticed her eye became red. She denies any trauma, eye pain, or visual disturbance. Physical examination reveals a subconjunctival hemorrhage. Which statement is accurate pertaining to this case?
- A. The hemorrhage will resolve without treatment within 2 weeks.
- B. The patient should be referred for immediate ophthalmologic examination.
- C. Corticosteroid eye drops will be prescribed to reduce the bleeding.
- D. Antibiotic eye drops will be prescribed to prevent infection.
Correct answer: A
Rationale: The correct answer is A: 'The hemorrhage will resolve without treatment within 2 weeks.' Subconjunctival hemorrhage typically resolves on its own without treatment. It is a self-limiting condition that does not require specific intervention. Choice B is incorrect as immediate ophthalmologic examination is not necessary for subconjunctival hemorrhage unless there are other concerning symptoms or risk factors present. Choice C is incorrect because corticosteroid eye drops are not typically used for subconjunctival hemorrhage. Choice D is also incorrect as antibiotic eye drops are not indicated since subconjunctival hemorrhage is not due to an infection.
4. Cushing syndrome is characterized by which disorder?
- A. Hypocortisolism
- B. Exophthalmos
- C. Hypercortisolism
- D. Hyperpigmentation
Correct answer: C
Rationale: Cushing syndrome is characterized by hypercortisolism, which is an excessive amount of cortisol in the body. Choice A, 'Hypocortisolism,' is incorrect as Cushing syndrome is associated with elevated cortisol levels. Choice B, 'Exophthalmos,' refers to bulging eyes and is not a characteristic feature of Cushing syndrome. Hyperpigmentation, as mentioned in choice D, can be present in Cushing syndrome due to increased ACTH levels stimulating melanocytes, but it is not the defining characteristic of the syndrome.
5. What is the action of amphotericin B?
- A. It binds to ergosterol and forms holes in the membrane.
- B. It binds to an enzyme required for the synthesis of ergosterol.
- C. It disrupts the fungal cell walls rather than the cell membrane.
- D. It inhibits glucan synthetase required for glucan synthesis.
Correct answer: A
Rationale: Amphotericin B is an antifungal medication that acts by binding to ergosterol, a component of fungal cell membranes, forming pores that disrupt the integrity of the membrane. This action leads to leakage of cellular contents and ultimately cell death. Choice B is incorrect as amphotericin B does not bind to an enzyme required for the synthesis of ergosterol. Choice C is incorrect as the drug primarily affects the cell membrane rather than the cell wall. Choice D is also incorrect as amphotericin B does not inhibit glucan synthetase.
Similar Questions
Access More Features
ATI RN Basic
$69.99/ 30 days
- 5,000 Questions with answers
- All ATI courses Coverage
- 30 days access
ATI RN Premium
$149.99/ 90 days
- 5,000 Questions with answers
- All ATI courses Coverage
- 30 days access