The main reason for the use of combination therapy in the drug treatment of Tuberculosis is:

Correct Answer: B

Rationale: The main reason for using combination therapy in TB treatment is to delay or prevent the emergence of resistance. Step 1: TB is caused by Mycobacterium tuberculosis, which has a high mutation rate leading to drug resistance. Step 2: With combination therapy, multiple drugs target different aspects of the bacteria's lifecycle, making it harder for resistance to develop. Step 3: This approach ensures that if one drug becomes ineffective due to resistance, others can still be effective. Summary: Choice B is correct as it directly addresses the issue of resistance, which is a critical concern in TB treatment. Choices A, C, and D are incorrect because reducing side effects, increasing antimycobacterial activity, and providing prophylaxis against other bacterial infections are not the primary reasons for using combination therapy in TB.

Correct Answer: D

Rationale: Thiazide diuretics can lead to hyperglycemia by reducing insulin sensitivity. This can result in increased blood glucose levels. Thiazides also elevate uric acid levels by reducing its excretion. Therefore, the correct answer is D (Glucose). Incorrect choices: A (Potassium) - Thiazides typically cause hypokalemia, not hyperkalemia. B (BUN) and C (Urea) - Thiazides may cause a slight increase in BUN and serum creatinine levels due to reduced kidney function, but not as significantly as glucose levels.

Correct Answer: D

Rationale: The correct answer is D: Furosemide. Furosemide is a loop diuretic which can increase uric acid levels in the blood, potentially worsening the patient's condition. Ethacrynic acid (A) is also a loop diuretic and can have similar effects. Acetazolamide (B) is a carbonic anhydrase inhibitor and may increase urinary excretion of uric acid, which can be beneficial in this case. Hydrochlorothiazide (C) is a thiazide diuretic that can actually lower uric acid levels by increasing urinary excretion. Therefore, the best choice to avoid in a patient with high plasma uric acid and risk of acute uric acid nephropathy is furosemide.

Correct Answer: C

Rationale: The correct answer is C: Gentamycin. Gentamycin is known to have potential nephrotoxicity, which can exacerbate renal dysfunction caused by furosemide. It should be avoided in patients with CHF and UTI. Cotrimoxazole (A) can be used with caution, Ciprofloxacin (B) is generally safe, and Ampicillin (D) is a suitable choice for UTI treatment in this scenario.