Tuberculosis

Question 1

What organism causes TB?

Answer 1

Mycobacterium tuberculosis, an aerobic, acid-fast bacillus.

Question 2

How is TB transmitted?

Answer 2

Inhalation of airborne droplets from a person with active pulmonary TB.

Question 3

What proportion of infected people develop active TB?

Answer 3

About 5–10%; the rest develop latent TB.

Question 4

What is the biggest risk factor for progression to active TB?

Answer 4

HIV infection (16-fold increased risk).

Question 5

Name three clinical features of pulmonary TB.

Answer 5

Chronic cough, haemoptysis, night sweats.

Question 6

Name two systemic symptoms of TB that should always raise suspicion.

Answer 6

Weight loss and persistent fevers.

Question 7

What is the hallmark chest X-ray finding in reactivation TB?

Answer 7

Upper lobe cavitation.

Question 8

What finding suggests miliary TB?

Answer 8

Diffuse, tiny “millet seed” nodules throughout both lungs.

Question 9

What is the classic neurological manifestation of TB?

Answer 9

Tuberculous meningitis (basal meningitis).

Question 10

What is Pott’s disease?

Answer 10

TB infection of the spine causing vertebral destruction and kyphosis.

Question 11

Which extrapulmonary TB causes pericardial shock?

Answer 11

TB pericarditis with effusion or constriction.

Question 12

What are the two screening tests for latent TB?

Answer 12

Mantoux test and interferon-gamma release assay (IGRA).

Question 13

What is the gold standard test for diagnosing active TB?

Answer 13

Sputum culture (slow but definitive).

Question 14

What rapid test identifies rifampicin resistance?

Answer 14

PCR gene assay (e.g., GeneXpert).

Question 15

What imaging is essential for suspected CNS TB?

Answer 15

CT or MRI head.

Question 16

What is the first-line regimen for active pulmonary TB?

Answer 16

2 months RIPE (rifampicin, isoniazid, pyrazinamide, ethambutol) followed by 4 months rifampicin + isoniazid.

Question 17

What drug must always be co-prescribed with isoniazid?

Answer 17

Pyridoxine (prevents neuropathy).

Question 18

What is the treatment for latent TB?

Answer 18

3 months isoniazid + rifampicin OR 6 months isoniazid.

Question 19

How long is TB meningitis treated for?

Answer 19

Minimum 12 months.

Question 20

What is the management for MDR-TB?

Answer 20

Combination of ≥6 drugs for 18–24 months.

Question 21

What toxicity is associated with rifampicin?

Answer 21

Hepatotoxicity and orange-red body fluid discolouration.

Question 22

What toxicity is associated with isoniazid?

Answer 22

Peripheral neuropathy.

Question 23

What toxicity is associated with ethambutol?

Answer 23

Optic neuritis causing red–green colour blindness.

Question 24

What toxicity is associated with pyrazinamide?

Answer 24

Hyperuricaemia and arthralgia.

Question 25

Name two TB complications seen after lung healing.

Answer 25

Bronchiectasis and aspergilloma formation.

Question 26

How effective is TB treatment?

Answer 26

Around 90% cure rate with correct therapy.

Question 27

What is the mortality of untreated smear-positive TB?

Answer 27

Up to 70% at 10 years.