TB

Question 1

Aetiology

Answer 1

Mycobacterium tuberculosis
Stain red of Zielh Nielsen
spread by air droplet

Question 2

Pathogenesis

Answer 2

Activation of macrophages and other inflammatory cells

Formation of granulomas

Question 3

Presentation

Answer 3

Lethargy
Fever or night sweats
Weight loss
Cough with or without haemoptysis
Lymphadenopathy
Erythema nodosum
Spinal pain in spinal TB (also known as Pott’s disease of the spine)

Question 4

Investigations

Answer 4

• Sputum culture of ziehl Nielsen : may require aspiration and bronchial lavage
• Blood cultures
• Lymph node aspiration/ biopsy
• Nucleic acid amplification test
• CXR
• Mantoux test
• Interferon gamma release assays

Question 5

Other considerations in testing?

Answer 5

• Isolation
• Test contacts
• Test for HIV, HEP B, HEP C
• Raise awareness with public health
• Treatment of extra pulmonary TB often involves CCS

Question 6

Treatment of TB

Answer 6

RIPE 
2 months of 
- Rifampicin 
- Isoniazid
- Pyrazinamide 
- Ethambutol 

4 months of

• Isoniazid
• Rifampicin

Question 7

Side of effects of drugs used in treatment

Answer 7

Rifampicin: Orange urine
Isoniazid: Peripheral neuropathy
Pyrazinamide: hyperuricemia which can lead to gout
Ethambutol: Optic neuritis

Question 8

What would a chest Xray show?

Answer 8

Primary TB: may show patchy consolidation, pleural effusions and hilar lymphadenopathy
Reactivated TB: may show patchy or nodular consolidation with cavitation (gas filled spaces in the lungs) typically in the upper zones
Disseminated Miliary TB: give a picture of “millet seeds” uniformly distributed throughout the lung fields