Tuberculosis MCQs With Answer

Tuberculosis MCQs With Answer offers B. Pharm students a focused, exam-oriented review of TB pharmacology, diagnosis, and therapeutics. This concise guide covers Mycobacterium tuberculosis biology, first- and second-line anti-TB drugs, mechanisms of action, adverse effects, resistance patterns (MDR/XDR), diagnostics like GeneXpert and culture, DOTS strategy, and clinical considerations including TB-HIV coinfection and pregnancy. Each MCQ is designed to reinforce core concepts, clinical reasoning, and practical pharmacy implications—drug interactions, monitoring, and patient counseling. Ideal for semester exams, competitive tests, and revision, these questions blend theory with application for pharmacy practice. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which organism is the primary causative agent of pulmonary tuberculosis?

• Mycobacterium tuberculosis
• Mycobacterium leprae
• Streptococcus pneumoniae
• Staphylococcus aureus

Correct Answer: Mycobacterium tuberculosis

Q2. What distinctive component of the mycobacterial cell wall contributes to acid-fastness and virulence?

• Mycolic acids
• Peptidoglycan cross-links
• Lipopolysaccharide
• Teichoic acids

Correct Answer: Mycolic acids

Q3. Which staining method is classically used to demonstrate acid-fast bacilli in sputum?

• Ziehl-Neelsen stain
• Gram stain
• India ink
• Wright stain

Correct Answer: Ziehl-Neelsen stain

Q4. Which finding best differentiates active pulmonary TB from latent TB infection?

• Presence of clinical symptoms and positive sputum culture
• History of BCG vaccination
• Positive Mantoux test only
• Positive interferon-gamma release assay only

Correct Answer: Presence of clinical symptoms and positive sputum culture

Q5. What is the most common primary site of tuberculosis infection?

• Lungs (pulmonary TB)
• Liver
• Skin
• Bone marrow

Correct Answer: Lungs (pulmonary TB)

Q6. Which combination lists the four standard first-line anti-TB drugs?

• Isoniazid, Rifampicin, Pyrazinamide, Ethambutol
• Streptomycin, Ciprofloxacin, Amikacin, Linezolid
• Bedaquiline, Delamanid, Clofazimine, PAS
• Penicillin, Amoxicillin, Ceftriaxone, Azithromycin

Correct Answer: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol

Q7. What is the primary mechanism of action of isoniazid (INH)?

• Inhibition of mycolic acid synthesis after activation by KatG
• Inhibition of DNA gyrase
• Inhibition of peptidoglycan cross-linking
• Disruption of membrane ion channels

Correct Answer: Inhibition of mycolic acid synthesis after activation by KatG

Q8. Rifampicin exerts its bactericidal effect by inhibiting which enzyme?

• DNA-dependent RNA polymerase
• DNA gyrase
• ATP synthase
• Peptidyl transferase

Correct Answer: DNA-dependent RNA polymerase

Q9. Pyrazinamide is most active under which condition and how does it act?

• Acidic pH; converted to pyrazinoic acid disrupting membrane energy metabolism
• Neutral pH; inhibits cell wall synthesis
• Alkaline pH; blocks protein synthesis
• Anaerobic conditions; inhibits folate synthesis

Correct Answer: Acidic pH; converted to pyrazinoic acid disrupting membrane energy metabolism

Q10. What is the mechanism of action of ethambutol?

• Inhibits arabinosyl transferase and impairs arabinogalactan synthesis
• Inhibits DNA gyrase
• Blocks ATP synthase
• Disrupts folate metabolism

Correct Answer: Inhibits arabinosyl transferase and impairs arabinogalactan synthesis

Q11. The most common neurological adverse effect of isoniazid is:

• Peripheral neuropathy due to pyridoxine deficiency
• Optic neuritis
• Ototoxicity
• Seizures due to hyperexcitability

Correct Answer: Peripheral neuropathy due to pyridoxine deficiency

Q12. Which adverse effect and pharmacokinetic property is characteristic of rifampicin?

• Potent CYP450 inducer causing multiple drug interactions
• Major renal clearance with nephrotoxicity
• Causes tendon rupture
• Directly causes hyperuricemia

Correct Answer: Potent CYP450 inducer causing multiple drug interactions

Q13. Which first-line anti-TB drug is most commonly associated with hyperuricemia?

• Pyrazinamide
• Isoniazid
• Rifampicin
• Ethambutol

Correct Answer: Pyrazinamide

Q14. Ethambutol toxicity primarily affects which organ system?

• Visual system causing optic neuritis and color vision defects
• Renal system causing tubular necrosis
• Gastrointestinal system causing severe colitis
• Cardiac system causing arrhythmias

Correct Answer: Visual system causing optic neuritis and color vision defects

Q15. What is the standard initial intensive-phase regimen for new, drug-susceptible pulmonary TB?

• 2 months of isoniazid, rifampicin, pyrazinamide and ethambutol (2HRZE)
• 6 months of isoniazid alone
• 2 months of streptomycin and ethambutol only
• 12 months of rifampicin monotherapy

Correct Answer: 2 months of isoniazid, rifampicin, pyrazinamide and ethambutol (2HRZE)

Q16. DOTS in tuberculosis control stands for:

• Directly Observed Treatment, Short-course
• Daily Oral Therapy Strategy
• Drug-Oriented Tuberculosis Service
• Direct Outpatient TB Surveillance

Correct Answer: Directly Observed Treatment, Short-course

Q17. GeneXpert MTB/RIF assay simultaneously detects Mycobacterium tuberculosis and resistance to which drug?

• Rifampicin
• Isoniazid
• Ethambutol
• Pyrazinamide

Correct Answer: Rifampicin

Q18. The Mantoux tuberculin skin test primarily measures which immunologic response?

• Delayed-type (Type IV) hypersensitivity to purified protein derivative (PPD)
• Immediate IgE-mediated hypersensitivity
• Complement fixation response
• Cell-free antibody neutralization

Correct Answer: Delayed-type (Type IV) hypersensitivity to purified protein derivative (PPD)

Q19. An advantage of interferon-gamma release assays (IGRAs) over Mantoux test is:

• Not affected by prior BCG vaccination
• Less expensive and widely available
• More useful for detecting active TB disease in resource-poor settings
• Can distinguish latent from active TB reliably

Correct Answer: Not affected by prior BCG vaccination

Q20. Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to at least:

• Isoniazid and rifampicin
• Ethambutol and pyrazinamide
• Streptomycin alone
• Any fluoroquinolone

Correct Answer: Isoniazid and rifampicin

Q21. Extensively drug-resistant TB (XDR-TB) includes MDR plus resistance to:

• Any fluoroquinolone and at least one second-line injectable (amikacin/kanamycin/capreomycin)
• All first-line drugs only
• Isoniazid plus ethambutol only
• Rifampicin plus pyrazinamide only

Correct Answer: Any fluoroquinolone and at least one second-line injectable (amikacin/kanamycin/capreomycin)

Q22. Bedaquiline, a newer anti-TB drug, targets which mycobacterial enzyme?

• ATP synthase
• RNA polymerase
• DNA gyrase
• Peptidyl transferase

Correct Answer: ATP synthase

Q23. Among first-line anti-TB drugs, which has the highest risk of hepatotoxicity?

• Pyrazinamide
• Ethambutol
• Streptomycin
• Ethionamide

Correct Answer: Pyrazinamide

Q24. Which anti-TB drug is contraindicated in pregnancy due to risk of fetal ototoxicity?

• Streptomycin
• Isoniazid
• Rifampicin
• Ethambutol

Correct Answer: Streptomycin

Q25. Recommended duration of isoniazid prophylaxis for latent TB in immunocompetent adults is typically:

• 6–9 months
• 2 weeks
• 24 months
• Lifetime therapy

Correct Answer: 6–9 months

Q26. Pyrazinamide requires which environment to be active against Mycobacterium tuberculosis?

• Acidic environment such as within macrophage phagolysosomes
• Alkaline extracellular fluid
• Anaerobic tissue sites only
• High oxygen tension only

Correct Answer: Acidic environment such as within macrophage phagolysosomes

Q27. A common mechanism of resistance to isoniazid involves mutation in which gene?

• katG leading to decreased activation of INH
• rpoB leading to altered RNA polymerase
• gyrA leading to altered DNA gyrase
• embB leading to altered arabinosyl transferase

Correct Answer: katG leading to decreased activation of INH

Q28. Rifampicin resistance is most frequently due to mutations in which gene?

• rpoB
• katG
• gyrA
• pncA

Correct Answer: rpoB

Q29. What baseline monitoring is recommended when starting ethambutol therapy?

• Visual acuity and color vision testing
• Baseline audiometry
• Thyroid function tests
• Routine ECG only

Correct Answer: Visual acuity and color vision testing

Q30. Therapeutic drug monitoring (TDM) is most useful for which anti-TB injectable used in MDR regimens?

• Amikacin
• Ethambutol
• Isoniazid
• Rifampicin

Correct Answer: Amikacin

Q31. One key advantage of fixed-dose combination (FDC) anti-TB tablets is:

• Improved adherence and reduced risk of monotherapy and resistance
• Lower cure rates compared to separate drugs
• Increased need for therapeutic drug monitoring
• Higher risk of individual drug toxicity due to unknown dosing

Correct Answer: Improved adherence and reduced risk of monotherapy and resistance

Q32. Rifampicin reduces plasma concentrations of many drugs because it:

• Induces hepatic cytochrome P450 enzymes
• Inhibits renal tubular secretion
• Blocks intestinal absorption non-specifically
• Directly inactivates co-administered drugs chemically

Correct Answer: Induces hepatic cytochrome P450 enzymes

Q33. Which diagnostic method remains the gold standard for confirming tuberculosis despite being slow?

• Mycobacterial culture
• Sputum smear microscopy
• Mantoux test
• Chest X-ray

Correct Answer: Mycobacterial culture

Q34. Typical culture time for growth of Mycobacterium tuberculosis on solid media is approximately:

• 3–6 weeks
• 24–48 hours
• 5–7 days
• 12 months

Correct Answer: 3–6 weeks

Q35. Sputum smear microscopy typically requires roughly how many bacilli per mL to be reliably positive?

• About 10^4 bacilli/mL
• 1 bacillus/mL
• 10^2 bacilli/mL
• 10^8 bacilli/mL

Correct Answer: About 10^4 bacilli/mL

Q36. Which anti-TB drug commonly causes orange-red discoloration of body fluids?

• Rifampicin
• Isoniazid
• Ethambutol
• Pyrazinamide

Correct Answer: Rifampicin

Q37. Which supplement is routinely coadministered with isoniazid to prevent peripheral neuropathy?

• Pyridoxine (vitamin B6)
• Folic acid
• Thiamine (vitamin B1)
• Vitamin C

Correct Answer: Pyridoxine (vitamin B6)

Q38. Pyrazinamide is relatively contraindicated in patients with which pre-existing condition?

• Gout due to risk of hyperuricemia
• Asthma due to bronchospasm risk
• Hypothyroidism due to TSH elevation
• Glaucoma due to increased intraocular pressure

Correct Answer: Gout due to risk of hyperuricemia

Q39. Total duration of standard therapy for drug-susceptible pulmonary TB is typically:

• 6 months
• 2 months
• 12 months
• 3 years

Correct Answer: 6 months

Q40. The BCG vaccine primarily protects young children against which severe forms of TB?

• Miliary TB and TB meningitis
• Pulmonary cavitary TB in adults
• Drug-resistant TB strains
• Latent TB infection in adolescents

Correct Answer: Miliary TB and TB meningitis

Q41. The central purpose of directly observed therapy (DOT) is to:

• Ensure adherence to therapy and reduce development of resistance
• Provide injectable drugs only
• Replace all outpatient visits with home delivery of drugs
• Reduce cost by shortening therapy arbitrarily

Correct Answer: Ensure adherence to therapy and reduce development of resistance

Q42. A rapid molecular test that can detect rifampicin resistance within hours is:

• GeneXpert MTB/RIF
• Ziehl-Neelsen smear
• LJ culture on solid media
• Mantoux test

Correct Answer: GeneXpert MTB/RIF

Q43. Which fluoroquinolone is commonly used as a core second-line agent in MDR-TB regimens?

• Moxifloxacin
• Ciprofloxacin (topical only)
• Nalidixic acid
• Metronidazole

Correct Answer: Moxifloxacin

Q44. Which first-line anti-TB drug is primarily bacteriostatic rather than bactericidal?

• Ethambutol
• Isoniazid
• Rifampicin
• Pyrazinamide

Correct Answer: Ethambutol

Q45. Para-aminosalicylic acid (PAS) acts primarily by interfering with which metabolic pathway in mycobacteria?

• Folate synthesis (antimetabolite action)
• Peptidoglycan cross-linking
• ATP synthesis
• RNA elongation

Correct Answer: Folate synthesis (antimetabolite action)

Q46. Which class of antibiotics used in TB regimens carries a risk of tendon rupture?

• Fluoroquinolones (e.g., levofloxacin)
• Aminoglycosides (e.g., amikacin)
• Macrolides (e.g., azithromycin)
• Beta-lactams (e.g., amoxicillin)

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

Q47. Delamanid, used for drug-resistant TB, belongs to which chemical class and acts by inhibiting:

• Nitroimidazole class; inhibits mycolic acid synthesis
• Aminoglycoside class; inhibits 30S ribosomal subunit
• Macrolide class; inhibits 50S ribosomal subunit
• Fluoroquinolone class; inhibits DNA gyrase

Correct Answer: Nitroimidazole class; inhibits mycolic acid synthesis

Q48. In HIV-TB coinfection when using protease inhibitors, which rifamycin is preferred due to fewer interactions?

• Rifabutin
• Rifampicin
• Rifapentine
• Rifaximin

Correct Answer: Rifabutin

Q49. The primary rationale for using multi-drug regimens in TB therapy is to:

• Prevent emergence of drug resistance by attacking different targets
• Reduce pill burden by prescribing more drugs
• Increase cost to ensure better healthcare funding
• Delay treatment initiation until sensitivity results are back

Correct Answer: Prevent emergence of drug resistance by attacking different targets

Q50. Before initiating standard anti-TB therapy, which baseline laboratory test is essential to assess risk of hepatotoxicity?

• Liver function tests (LFTs)
• Urine pregnancy test only
• Serum amylase only
• Complete blood count only

Correct Answer: Liver function tests (LFTs)

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