Final Exam Pathophysiology

Correct Answer: C

Rationale: The correct answer is C. Oral contraceptives can be less effective when taken with certain antibiotics as they may interfere with the contraceptive's efficacy, potentially leading to decreased effectiveness. Therefore, patients should be advised to use additional contraception methods if they are also taking antibiotics. Choice A is incorrect because while oral contraceptives are highly effective, they are not 100% foolproof. Choice B is incorrect as oral contraceptives may take some time to reach their full effectiveness after starting. Choice D is incorrect since taking oral contraceptives with food does not necessarily impact their effectiveness.

Correct Answer: C

Rationale: After the administration of interferon alfa-2b, the patient may develop flu-like symptoms as an adverse effect. Flu-like symptoms are commonly associated with interferon therapy, including fever, chills, fatigue, and muscle aches. These symptoms usually subside over time. Options A, B, and D are not typically associated with interferon alfa-2b administration. Profound diaphoresis is excessive sweating, decreased level of consciousness indicates neurological issues, and cyanosis and pallor suggest circulatory or respiratory problems, none of which are expected adverse effects of interferon alfa-2b.

Correct Answer: A

Rationale: The correct answer is A: Diarrhea. Hepatotoxicity caused by isoniazid can present with various symptoms, including yellow discoloration of the sclera of the eyes, which indicates jaundice. Another common sign of hepatotoxicity is gastrointestinal symptoms such as nausea, vomiting, and diarrhea, which can occur due to liver dysfunction affecting bile production and digestion. Numbness (choice B) is more commonly associated with peripheral neuropathy caused by isoniazid, while diminished vision (choice C) and light-colored stools (choice D) are not typical manifestations of hepatotoxicity.

Correct Answer: C

Rationale: The correct answer is C: IgE. A severe allergic reaction, such as the one experienced by the 10-year-old male after being stung by a bee, is mediated by IgE. IgE is involved in common allergic responses, triggering the release of histamine and other chemicals that lead to allergy symptoms. Choice A, Toxoids, are inactivated toxins used in vaccines. Choice B, IgA, is mainly found in mucosal areas and secretions, playing a role in mucosal immunity. Choice D, IgM, is the first antibody produced in response to an infection.

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.