Tuberculosis

Question 1

What is TB caused by?

Answer 1

Mycobacterium tuberculosis

Question 2

What is special about mycobacterium tuberculosis?

Answer 2

Rod shaped, waxy coating mean gram staining is ineffective. Acid- fastness. Require Zeihl Nielsen stain- turn bright red against blue background

Question 3

How do you catch TB?

Answer 3

Inhaling saliva droplets- through lymphatic and blood.

Question 4

What do you get in TB?

Answer 4

Granulomas form

Question 5

What is latent TB?

Answer 5

Immune system encapsulates sites of infection and stops progression

Question 6

Extrapulmonary TB?

Answer 6

Lymph nodes- cold abscess usually in neck
Pleura
CNS
Pericardium
GI
GUI
Bones and joint
Cutaneous TB

Question 7

Risk factors for TB?

Answer 7

Known contact, immigrant from TB prevalence, immunosuppressed (HIV), homeless people drug users alcoholics,

Question 8

What should be done before someone is given BCG vaccine?

Answer 8

Mantoux test and check for immunosuppressive and HIV

Question 9

Presentation of TB?

Answer 9

Lymphadenopathy
Erythema no dorsum
Lethargy
Night sweats
Fever
Cough with/out haemoptysis
Weight loss
Spinal pain (Potts)

Question 10

2 tests for checking persons TB status?

Answer 10

Mantoux test and interferon gamma release assay

Question 11

What can you use to support diagnosis of TB?

Answer 11

CXR and cultures

Question 12

What is the Mantoux test?

Answer 12

Inject tuberculin - bleb after 72 hours it will be read. Induration of 5mm or more is positive

Question 13

What is interferon gamma release assay?

Answer 13

Sample of blood and mixing with TB antigen. If person previously had TB, WBC will release interferon gamma

Question 14

What would CXR show for TB?

Answer 14

Primary- patchy consolidation, hilar lymphadenopathy and pleural effusion
Reactivated TB- patchy or modular consolidation with cavitation in upper zones
Military TB- millet seeds

Question 15

How to collect cultures?

Answer 15

1. Sputum bronchoscopy and lavage
2. Mycobacterium blood cultures
   Lymph node aspiration or biopsy

Question 16

Management of latent TB?

Answer 16

If at risk of reactivation:
Isoniazid and rifampicin for 3 months
Isoniazid for 6 months

Question 17

Management of active TB?

Answer 17

RIPE
Rifampicin 6 months
Isoniazid 6 months
Pyrazinamide 2 months
Ethambutol 2 months

Question 18

What can isoniazid cause and what is given with it prophylactically?

Answer 18

Peripheral neuropathy, pyridoxine B6

Question 19

If extrapulmonary disease what should be used?

Answer 19

Corticosteroids

Question 20

Side effects of rifampicin?

Answer 20

Red and orange colour of urine and tears. Potent inducer of cytochrome p450

Question 21

Side effect of pyrazinamide?

Answer 21

Hyperuricaemia - gout

Question 22

Side effects of ethambutol?

Answer 22

Colour blindness and reduced visual acuity

Question 23

Which medications cause hepatotoxicity?

Answer 23

Rifampicin isoniazid and pyrazinamide

Question 24

What is the waxy cell wall made of?

Answer 24

Mycolic acid

Question 25

What happens to granuloma?

Answer 25

WBCs contain the bacterium. Caseous necrosis- ghon focus

Question 26

Ghon complex is made up of?

Answer 26

Ghon focus and hilar lymph nodes

Question 27

Where do Ghon complexes occur?

Answer 27

Lower lobes

Question 28

A calcified necrotic ghon complex is called?

Answer 28

Ranke complex

Question 29

Systemic military TB?

Answer 29

1. Kidneys- sterile puria (WBCs in urine) 2. Meningitis 3. Potts 4.Lymphadenitis in neck (scrofula) 5. Hepatitis 6. Addison’s disease

Question 30

What type of hypersensitive reaction is TB?

Answer 30

4

Question 31

If induration is more than 15mm suggests

Answer 31

Active

Question 32

Patients with meningeal TB are treated?

Answer 32

12 months with addition of steroids

Question 33

What is a complication of treatment?

Answer 33

Immune reconstitution disease 3-6 weeks after treatment. Enlarging lymph nodes

Question 34

What is isoniazid?

Answer 34

Liver enzyme inhibitor.