A 31-year-old man has gonorrhea. He has no drug allergies, but he recalls that a few years ago while in Africa he had acute hemolysis following use of an antimalarial drug. The physician is concerned that the patient has an accompanying urethritis due to C trachomatis, though no cultures or enzyme tests have been performed. Which of the following drugs is most likely to be effective against gonococci and to eradicate C trachomatis in this patient?

Correct Answer: A

Rationale: The correct answer is A) Cefixime. Cefixime is a third-generation cephalosporin antibiotic that is effective against both gonococci and Chlamydia trachomatis, making it an appropriate choice for this patient with suspected dual infection. Ciprofloxacin (B) and Ofloxacin (C) are fluoroquinolone antibiotics that were previously used to treat gonorrhea and chlamydia, but due to increasing resistance, they are no longer recommended as first-line treatments. Spectinomycin (D) is an alternative treatment for gonorrhea but does not provide coverage against Chlamydia trachomatis. In an educational context, it is important for healthcare providers to stay updated on current treatment guidelines for sexually transmitted infections like gonorrhea and chlamydia due to the evolving antibiotic resistance patterns. Understanding the mechanisms of action and spectrum of coverage of different antibiotics is crucial in selecting the most appropriate treatment for individual patients to ensure successful eradication of the infections and prevent further complications or resistance development.

Correct Answer: D

Rationale: In the treatment of tuberculosis, the primary reason for using drug combinations is to delay or prevent the emergence of resistance (Option D). This is because tuberculosis is caused by Mycobacterium tuberculosis, a bacterium known for its ability to develop resistance to single drugs quickly. By using a combination of drugs with different mechanisms of action, it becomes harder for the bacteria to mutate and become resistant to all drugs simultaneously, thus preserving treatment efficacy. Option A (Ensuring patient compliance) is important in tuberculosis treatment, but the primary reason for combination therapy is not just patient compliance. While compliance is crucial, it is not the primary reason for using drug combinations. Option B (Reducing adverse effects) is a consideration in treatment, but the main purpose of drug combinations in tuberculosis is not solely to reduce adverse effects. It is primarily to prevent resistance. Option C (Enhancing activity against metabolically inactive mycobacteria) is a valid consideration, but the primary reason for combination therapy in tuberculosis is to combat resistance rather than targeting metabolically inactive bacteria. Educationally, understanding the rationale behind using drug combinations in tuberculosis treatment is essential for nurses, pharmacists, and other healthcare professionals to provide effective care, prevent resistance, and ensure successful treatment outcomes in patients with tuberculosis. This knowledge helps in making informed decisions regarding treatment strategies and reinforces the importance of adherence to prescribed medication regimens to combat this infectious disease effectively.

Correct Answer: D

Rationale: The correct answer is D) Rifampin. Rifampin is a broad-spectrum antibiotic commonly used in the prophylaxis of Haemophilus influenzae type B infections, meningococcal infections, and staphylococcal carrier states. It is effective in eradicating meningococci from carriers; however, there is a risk of selecting out highly resistant strains during treatment. A) Ciprofloxacin is a broad-spectrum antibiotic commonly used in urinary tract infections and respiratory infections. It is not typically used for prophylaxis in the mentioned conditions. B) Clofazimine is an antimycobacterial agent used in the treatment of leprosy. It does not have a role in prophylaxis for Haemophilus influenzae, meningococcal infections, or staphylococcal carrier states. C) Dapsone is primarily used in the treatment of leprosy and dermatitis herpetiformis. It is not indicated for the prophylaxis of the mentioned bacterial infections. Educational Context: Understanding the indications and mechanisms of action of different chemotherapy drugs is crucial for healthcare professionals, especially for nurses and pharmacists who may administer these medications. Knowledge of specific drugs, their uses, and potential side effects is essential for safe and effective patient care. In the case of rifampin, understanding its role in prophylaxis against specific bacterial infections helps in preventing the spread of these diseases and in selecting appropriate treatment options based on individual patient needs and conditions.

Correct Answer: D

Rationale: Chemotherapy drugs are designed to target rapidly dividing cells, like cancer cells, by disrupting their cellular processes. In the given question, the correct answer is D) Nystatin. Nystatin is an antifungal medication that interacts with cell membrane components to form pores lined by hydrophilic groups in the drug molecule. This disrupts the fungal cell membrane, leading to cell death. Option A) Dactinomycin is an antibiotic used in cancer treatment, but it works by intercalating into DNA, not by forming pores in cell membranes as described in the question. Option B) Griseofulvin is another antifungal drug, but it acts by disrupting fungal cell division, not by forming pores in cell membranes. Option C) Fluconazole is an antifungal agent that inhibits ergosterol synthesis in fungal cell membranes, not by forming pores lined by hydrophilic groups. Understanding the mechanisms of action of chemotherapy drugs is crucial for nurses and healthcare professionals to ensure safe and effective administration. Knowing how each drug interacts with cellular components helps in predicting their side effects and understanding their therapeutic effects. This knowledge is essential for passing exams like the NCLEX and for providing quality patient care in clinical practice.

Correct Answer: A

Rationale: Flucytosine is an antifungal medication used to treat systemic fungal infections. The correct statement, "It is bioactivated by fungal cytosine deaminase," is accurate because flucytosine requires conversion by fungal enzymes to its active form, 5-fluorouracil, which inhibits fungal DNA synthesis. This specific mode of action targets fungal cells while minimizing toxicity to human cells. Option B, "It does not cross the blood-brain barrier," is incorrect. Flucytosine does penetrate the blood-brain barrier, making it useful in treating fungal infections of the central nervous system. Option C, "It inhibits cytochrome P450," is incorrect. Flucytosine does not have a significant effect on cytochrome P450 enzymes. Option D, "It is useful in esophageal candidiasis," is incorrect. Flucytosine is not typically used to treat esophageal candidiasis; it is more commonly used for systemic fungal infections. In an educational context, understanding the mechanism of action of chemotherapy drugs like flucytosine is essential for safe and effective medication administration. Nurses and healthcare professionals need to grasp how these drugs work to provide optimal care for patients receiving chemotherapy. Additionally, knowledge of the pharmacokinetics and pharmacodynamics of flucytosine can help prevent adverse drug reactions and ensure therapeutic success in treating fungal infections.