TB

Question 1

What is tuberculosis (TB)?

Answer 1

An infectious disease caused by Mycobacterium tuberculosis that primarily affects the lungs but can spread to other organs.

Question 2

What are historical names for TB?

Answer 2

Phthisis, King’s Evil, White Plague, Vampirism.

Question 3

Who is at higher risk of developing active TB?

Answer 3

Elderly, infants, immunocompromised individuals (e.g., AIDS, chemotherapy), malnourished, healthcare workers, those in crowded living conditions.

Question 4

How is TB transmitted?

Answer 4

Person-to-person through airborne droplet nuclei (1-5μm) during coughing, sneezing, talking, laughing, or singing.

Question 5

What is the causative organism of TB?

Answer 5

Mycobacterium tuberculosis, an aerobic, acid-fast, non-motile bacillus with high lipid content.

Question 6

What is the global epidemiology of TB?

Answer 6

1.9 billion people are infected; 10 million develop active TB yearly; TB kills 5,000 people daily.

Question 7

What is the ranking of Nigeria in TB burden?

Answer 7

Nigeria ranks 1st in Africa and 6th globally, contributing 4.6% to the global TB burden.

Question 8

What are the clinical features of pulmonary TB?

Answer 8

Cough (productive or haemoptysis), fever, weight loss, night sweats, anorexia, fatigue.

Question 9

What are the key cells involved in TB immunity?

Answer 9

Macrophages (phagocytose M.tb) and CD4+ T lymphocytes (produce lymphokines for protection).

Question 10

What laboratory specimens are used to diagnose TB?

Answer 10

Sputum, gastric washout, pleural aspirate, stool, and others.

Question 11

What is the gold standard for TB diagnosis?

Answer 11

Culture, which is more sensitive than microscopy and detects 10–100 bacilli per mL of sample.

Question 12

What are the first-line drugs for TB treatment?

Answer 12

Isoniazid (INH), Rifampicin (RIF), Pyrazinamide (PZA), Ethambutol (EMB), and Streptomycin.

Question 13

What is the DOTS strategy in TB treatment?

Answer 13

Directly Observed Treatment Short-course, where patients are observed taking medications to ensure treatment completion.

Question 14

What is the treatment regimen for TB?

Answer 14

Six months: Intensive phase (2 months with INH, RIF, PZA, EMB/Streptomycin) followed by continuation phase (4 months with INH and RIF).

Question 15

What is multidrug-resistant TB (MDR-TB)?

Answer 15

TB resistant to isoniazid and rifampicin, with or without resistance to other drugs.

Question 16

What is extensively drug-resistant TB (XDR-TB)?

Answer 16

MDR-TB resistant to fluoroquinolones and at least one injectable second-line drug (amikacin, capreomycin, or kanamycin).

Question 17

What is the role of BCG in TB prevention?

Answer 17

BCG vaccine prevents severe TB forms in children but has variable efficacy against pulmonary TB in adults.

Question 18

What are the methods of TB diagnosis?

Answer 18

Microscopy (Ziehl-Neelsen), culture, tuberculin skin test (TST), interferon-gamma release assays (IGRA), and molecular techniques (e.g., GeneXpert).

Question 19

What does a positive Mantoux test indicate?

Answer 19

Induration ≥5mm in high-risk individuals (e.g., HIV+, recent TB contact); ≥10mm in moderate-risk individuals (e.g., immigrants, lab personnel); ≥15mm in low-risk individuals.

Question 20

What are preventive measures for TB?

Answer 20

Vaccination (BCG), avoiding overcrowding, maintaining personal hygiene, proper nutrition, and public education.

Question 21

What are second-line drugs for TB treatment?

Answer 21

Cycloserine, Para-aminosalicylic acid (PAS), Ethionamide, Amikacin, Kanamycin, Capreomycin, Levofloxacin.