Tuberculosis

Question 1

How many people are effected with Tuberculosis worldwide?

Answer 1

2 Billion

Question 2

What percentage of UK TB sufferers live in London?

Answer 2

39%

Question 3

What percentage of TB patients are HIV+?

Answer 3

~10%

Question 4

What bacteria cause tuberculosis?

Answer 4

Mycobacterium tuberculosis/bovis

Question 5

How do you test for TB pathogens?

Answer 5

Acid Alcohol Fast Bacilli

ZN stain

Question 6

What factors can turn a resistant host into a susceptible host?

Answer 6

Malnutrition and Age

Question 7

What is MOTT?

Answer 7

Mycobacteria other then Tuberculosis
Mycobacterium avium-intracellulare
M. kansasii, malmoense, xenophi

Question 8

What type of bacterium is mycobacteria?

Answer 8

Slow growing, aerobic, non-motile bacillus

Question 9

What is mycobacteria resistant to?

Answer 9

Acids, alkali, detergents

Neutrophils/macrophages

Question 10

What part of the lung is most vulnerable to TB? Why?

Answer 10

Apex of lobes

Parts of lungs ventilated but not perfused

Question 11

M. tuberculosis spreads how?

Answer 11

Inhaling droplets containing mycobacteria

Question 12

M. bovis spreads how?

Answer 12

Consumption of infected cows milk

Question 13

Secondary infection triggers what?

Answer 13

Activation of macrophages causes damage, epithelioid cells propagate to repair

Question 14

Macrophages and epithelioid cells form what?

Answer 14

Langhans giant cells

Question 15

Langhan’s cells, macrophages and epitheloid cells form what?

Answer 15

Granuloma

Question 16

What types of granuloma are common in TB?

Answer 16

Central Caseating Granuloma (may later calcify)

Question 17

What happens on exposure to a resistant host?

Answer 17

Rapid immune response causing a small amount of damage

Question 18

What happens on exposure to a susceptible host?

Answer 18

Large amounts of tissue damage with pathogen survival

Question 19

How does mycobacterium spread systemically?

Answer 19

Via Hilar lymph nodes

Question 20

How does primary TB present in the majority?

Answer 20

Initial lesion + local lymph node

Heals with/without scar

Question 21

What is the basis of Heaf/Tuberculin tests?

Answer 21

Intradermal administration of tuberculoprotein based on immunity to said protein

Question 22

What are the three outcomes to primary TB infection?

Answer 22

Progressive Disease
Contained Latent
Cleared/cured

Question 23

Progression of primary infection presents with what?

Answer 23

Primary focus enlargement

Enlargement of hilar lymph nodes compressing bronchi

Question 24

What causes Tuberculous Bronchopneumonia?

Answer 24

Discharge of tuberculous lymph node into the bronchi

Question 25

Disseminated infection can appear as what?

Answer 25

Miliary TB Meningeal TB Tuberculous Pleural Effusion

Question 26

How does Miliary TB present?

Answer 26

Small widespread granulomata

Question 27

What is Post primary disease?

Answer 27

Reactivation of disseminated latent mycobacterium | New reinfection

Question 28

What is the clinical presentation of Pulmonary Tuberculosis?

Answer 28

Progressive cough Sputum (haemoptysis) Pleuritic pain Malaise, fever, weight loss, night sweats

Question 29

Common PMH in post-primary pulmonary TB?

Answer 29

Diabetes Immunosuppression Previous TB

Question 30

Social history in post-primary TB?

Answer 30

Alcohol, IVDA Poverty High incidence immigrants

Question 31

In which patients should you be suspicious of TB?

Answer 31

``` Immunosuppressed Malnutrition DM Young/Old High prevalence immigrants ```

Question 32

Which sputum tests should be done and when?

Answer 32

3 sputum specimens on successive days: Sputum smear (ZN stain) Sputum culture Sputum PCR

Question 33

What are the essential investigations for TB?

Answer 33

Sputum specimens | CXR

Question 34

What might you expect on a TB CXR?

Answer 34

Patchy shadowing at apices Cavitation Calcification

Question 35

What additional Investigations would you perform if the sputum tests were negative?

Answer 35

Thoracic CT Bronchoscopy with biopsy Pleural Aspiration (if pleural effusion)

Question 36

What surgery is used for TB?

Answer 36

Collapse cavity and resect (sometimes)

Question 37

What are the drugs used for tuberculosis?

Answer 37

Isoniazid Rifampicin Ethambutol Pyrazinamide

Question 38

How long after treatment begins is the patient non-infectious?

Answer 38

2 Weeks

Question 39

Side effects of Rifampicin

Answer 39

Iron Bru tears, urine Induced Liver enzymes Hepatitis

Question 40

Side effects of Isoniazid

Answer 40

Hepatitis | Peripheral neuropathy

Question 41

Ethambutol

Answer 41

Optic neuropathy

Question 42

Pyrazinamide

Answer 42

Gout

Question 43

Which drugs does Rifampicin render ineffective?

Answer 43

Prednisolone Anticonvulsants Oral contraceptive

Question 44

What are the goals of contact tracing in TB?

Answer 44

Identify source and possible transmissions

Question 45

When do you screen casual contacts of TB patients?

Answer 45

If close contacts infected suggesting high virulence

Question 46

What are the screening tests used for TB?

Answer 46

Mantoux | Heaf

Question 47

If younger than 16, no BCG, Heaf test positive, what do you do?

Answer 47

CXR | Chemoprophylaxis

Question 48

If younger than 16, no BCG, Heaf test negative. What do you do?

Answer 48

Repeat after 6 weeks