Chemotherapy of urinary tract infections MCQs With Answer

Chemotherapy of urinary tract infections MCQs With Answer

by

Chemotherapy of urinary tract infections MCQs With Answer offers B. Pharm students a focused review of antimicrobial pharmacology, clinical indications, dosing, pharmacokinetics, resistance mechanisms and adverse effects relevant to UTI management. This resource emphasizes key drugs—nitrofurantoin, trimethoprim–sulfamethoxazole, fluoroquinolones, fosfomycin, beta‑lactams and aminoglycosides—alongside treatment of uncomplicated and complicated UTI, pyelonephritis, pregnancy considerations, renal dosing and stewardship principles. Expect questions on mechanism of action, spectrum of activity, microbial resistance, therapeutic monitoring and drug interactions to reinforce clinical decision‑making. Clear explanations will help you master antibiotic selection and safe use in special populations. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which antibiotic is considered first-line oral therapy for uncomplicated cystitis in non-pregnant adult women when local resistance of E. coli to this agent is low?

  • Nitrofurantoin 100 mg twice daily for 5 days
  • Ciprofloxacin 500 mg twice daily for 7 days
  • Azithromycin 500 mg single dose

Correct Answer: Nitrofurantoin 100 mg twice daily for 5 days

Q2. What is the primary mechanism of action of trimethoprim‑sulfamethoxazole in UTI therapy?

  • Inhibition of bacterial DNA gyrase
  • Sequential blockade of folate synthesis pathway
  • Disruption of cell membrane integrity
  • Inhibition of peptidoglycan transpeptidation

Correct Answer: Sequential blockade of folate synthesis pathway

Q3. Which agent is most appropriate as a single‑dose oral therapy for uncomplicated cystitis caused by susceptible organisms?

  • Fosfomycin trometamol 3 g single dose
  • Nitrofurantoin 100 mg twice daily for 5 days
  • Levofloxacin 500 mg daily for 3 days
  • Amoxicillin‑clavulanate 875/125 mg twice daily for 7 days

Correct Answer: Fosfomycin trometamol 3 g single dose

Q4. Which antibiotic has good prostatic tissue penetration and is commonly used for acute bacterial prostatitis?

  • Nitrofurantoin
  • Ciprofloxacin
  • Fosfomycin
  • Penicillin V

Correct Answer: Ciprofloxacin

Q5. Nitrofurantoin is contraindicated in patients with which condition due to reduced efficacy and increased risk of toxicity?

  • Creatinine clearance <30 mL/min
  • History of tendon rupture
  • G6PD deficiency
  • Pregnancy in first trimester

Correct Answer: Creatinine clearance <30 mL/min

Q6. Which organism is intrinsically resistant to nitrofurantoin and therefore not reliably treated by it?

  • Escherichia coli
  • Enterococcus faecalis
  • Klebsiella pneumoniae
  • Staphylococcus saprophyticus

Correct Answer: Klebsiella pneumoniae

Q7. A pregnant woman with asymptomatic bacteriuria should be treated because untreated bacteriuria increases risk of:

  • Placental abruption
  • Pyelonephritis and preterm birth
  • Gestational diabetes
  • Neural tube defects

Correct Answer: Pyelonephritis and preterm birth

Q8. Which UTI antibiotic’s major adverse effect includes tendonitis and risk of tendon rupture, especially in older adults?

  • Trimethoprim‑sulfamethoxazole
  • Fosfomycin
  • Fluoroquinolones (e.g., ciprofloxacin)
  • Nitrofurantoin

Correct Answer: Fluoroquinolones (e.g., ciprofloxacin)

Q9. For severe pyelonephritis requiring parenteral therapy, which class of antibiotics is commonly used empirically?

  • Oral macrolides
  • Third‑generation cephalosporins or extended‑spectrum penicillins
  • First‑generation cephalosporins only
  • Topical sulfonamides

Correct Answer: Third‑generation cephalosporins or extended‑spectrum penicillins

Q10. Which resistance mechanism confers high‑level resistance to penicillins and cephalosporins in Enterobacteriaceae and often necessitates carbapenem therapy?

  • Efflux pump overexpression
  • Target site mutation in DNA gyrase
  • Extended‑spectrum beta‑lactamase (ESBL) production
  • Ribosomal methylation

Correct Answer: Extended‑spectrum beta‑lactamase (ESBL) production

Q11. Methenamine is used as a urinary antiseptic; its antiseptic effect depends on urinary conversion to:

  • Urea
  • Formaldehyde
  • Nitric oxide
  • Hydrogen peroxide

Correct Answer: Formaldehyde

Q12. Trimethoprim alone predisposes to which adverse effect due to folate antagonism?

  • Hyperkalemia
  • Bone marrow suppression and megaloblastic anemia
  • Ototoxicity
  • Photosensitivity

Correct Answer: Bone marrow suppression and megaloblastic anemia

Q13. Which antimicrobial achieves high urinary concentrations but is ineffective for pyelonephritis because it does not achieve adequate renal parenchymal levels?

  • Nitrofurantoin
  • Fluoroquinolones
  • Aminoglycosides
  • Third‑generation cephalosporins

Correct Answer: Nitrofurantoin

Q14. In the setting of suspected Pseudomonas aeruginosa UTI, which agent provides reliable oral anti‑pseudomonal activity?

  • Fosfomycin
  • Nitrofurantoin
  • Ciprofloxacin
  • Amoxicillin

Correct Answer: Ciprofloxacin

Q15. Which laboratory parameter is most important to monitor during aminoglycoside therapy for complicated UTI?

  • Liver function tests
  • Serum creatinine and trough drug levels
  • Platelet count
  • Serum potassium alone

Correct Answer: Serum creatinine and trough drug levels

Q16. A urine culture shows an organism with a minimum inhibitory concentration (MIC) below the achievable urinary concentration of the drug; this implies the isolate is:

  • Resistant
  • Semi‑resistant
  • Sensitive (susceptible)
  • Not identifiable

Correct Answer: Sensitive (susceptible)

Q17. Which drug interaction is important with trimethoprim‑sulfamethoxazole and warfarin?

  • Sulfamethoxazole induces warfarin metabolism, decreasing INR
  • Sulfamethoxazole inhibits warfarin metabolism, increasing INR and bleeding risk
  • Trimethoprim increases renal clearance of warfarin
  • No clinically relevant interaction

Correct Answer: Sulfamethoxazole inhibits warfarin metabolism, increasing INR and bleeding risk

Q18. For recurrent UTIs in a non‑pregnant woman, which prophylactic strategy may be considered?

  • Daily low‑dose antibiotic prophylaxis or postcoital single dose therapy
  • Continuous high‑dose intravenous antibiotics
  • Avoiding all fluids to reduce urination
  • Long‑term topical antifungals

Correct Answer: Daily low‑dose antibiotic prophylaxis or postcoital single dose therapy

Q19. Which of the following is a common mechanism by which E. coli develops resistance to fluoroquinolones?

  • Production of beta‑lactamases
  • Mutation in DNA gyrase or topoisomerase IV
  • Altered folate synthesis enzymes
  • Plasmid‑mediated methylation of ribosomes

Correct Answer: Mutation in DNA gyrase or topoisomerase IV

Q20. In elderly patients with renal impairment, which adjustment is most critical when prescribing renally excreted UTI antibiotics?

  • Increase dose frequency
  • Reduce dose or extend dosing interval based on creatinine clearance
  • Avoid baseline renal function testing
  • Always choose drugs eliminated via bile only

Correct Answer: Reduce dose or extend dosing interval based on creatinine clearance

Q21. Which oral antibiotic is often avoided in pregnant women due to risk of fetal cartilage damage?

  • Nitrofurantoin
  • Fosfomycin
  • Fluoroquinolones (e.g., ciprofloxacin)
  • Cephalexin

Correct Answer: Fluoroquinolones (e.g., ciprofloxacin)

Q22. What is the rationale for obtaining urine culture and susceptibility testing before changing empiric therapy in complicated UTI?

  • To identify viral causes of UTI
  • To tailor antibiotic selection to the pathogen and resistance profile
  • To measure patient hydration status
  • To determine blood glucose control

Correct Answer: To tailor antibiotic selection to the pathogen and resistance profile

Q23. Trimethoprim‑sulfamethoxazole is bactericidal because:

  • Each component alone is bactericidal
  • Sequential blockade of folate synthesis leads to inhibition of nucleotide synthesis
  • It disrupts cell membrane potential
  • It causes DNA strand breaks directly

Correct Answer: Sequential blockade of folate synthesis leads to inhibition of nucleotide synthesis

Q24. Which adverse reaction is particularly associated with long‑term nitrofurantoin use?

  • Interstitial pulmonary fibrosis and chronic pulmonary reactions
  • Ototoxicity
  • Tendon rupture
  • Severe hyperglycemia

Correct Answer: Interstitial pulmonary fibrosis and chronic pulmonary reactions

Q25. In a hospitalized patient with suspected urosepsis, empiric broad‑spectrum therapy should be guided by:

  • Local antibiogram and patient allergy history
  • Only the cheapest available antibiotic
  • One‑time urine dipstick alone
  • Empiric antifungal therapy for all

Correct Answer: Local antibiogram and patient allergy history

Q26. Which beta‑lactam antibiotic combination provides reliable activity against many ESBL‑producing organisms?

  • Amoxicillin alone
  • Piperacillin‑tazobactam (may have variable efficacy)
  • Penicillin V
  • Cefazolin

Correct Answer: Piperacillin‑tazobactam (may have variable efficacy)

Q27. A patient with a UTI caused by Enterococcus faecalis should not be treated with which drug due to intrinsic resistance?

  • Ampicillin
  • Nitrofurantoin (may have activity for cystitis)
  • Cephalexin
  • Vancomycin (if susceptible)

Correct Answer: Cephalexin

Q28. Which pharmacokinetic property most directly affects an antibiotic’s ability to treat lower urinary tract infections?

  • High hepatic metabolism
  • High renal excretion and concentration in urine
  • High protein binding only
  • Extensive enterohepatic recycling

Correct Answer: High renal excretion and concentration in urine

Q29. When treating complicated UTI in a patient with known ESBL‑producing E. coli, the preferred class of antibiotics is usually:

  • Macrolides
  • Carbapenems (e.g., meropenem)
  • First‑generation cephalosporins
  • Oxazolidinones

Correct Answer: Carbapenems (e.g., meropenem)

Q30. Which statement about urine culture and sensitivity reporting is correct?

  • Susceptibility results are unnecessary if empiric therapy is working clinically
  • MIC values and breakpoint interpretations help determine if an organism is susceptible at achievable drug concentrations in urine
  • Only qualitative colony counts matter, not organism identification
  • All urinary isolates should always be treated regardless of symptoms

Correct Answer: MIC values and breakpoint interpretations help determine if an organism is susceptible at achievable drug concentrations in urine

Leave a Comment