Tuberculosis

Question 1

What is the history of TB?

Answer 1

Jean-Antoine Villemin successfully transmitted TB from a human to a rabbit and other animals
Robert Koch discovered that M. Tuberculosis was the etiological agent of TB

Question 2

Koch postulates for infections disease

Answer 2

1. The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy organisms.
2. The microorganism must be isolated from a diseased organism and grown in pure culture.
3. The cultured microorganism should cause disease when introduced into a healthy organism.
4. The microorganism must be re-isolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

Question 3

Historical references to TB

Answer 3

Referenced in Bible, and in Ancient Egyptian art

Question 4

Define Latent infection

Answer 4

Someone carries the disease but does not exhibit symptoms, 1/3 of population has latent TB, 10% of people who contract TB develop active TB disease

Question 5

Social Determinants of TB

Answer 5

TB is more common in areas of poverty, homelessness, crowding over 25% of TB disease is attributable to poor nutrition or infection

Question 6

Drug development issues/funding issues

Answer 6

affects the poorest, most drugs never make it to the market

Question 7

5 Diagnostic steps

Answer 7

1. Chest imaging
2. Sputum smear
3. Sputum culture
4. Molecular methods
5. Drug susceptibility tests
   theme of lack of equipment and expertise to interpret data

Question 8

What is DOTS

Answer 8

Directly Observed, Short Course

1. Sustained political and financial commitment.
2. Diagnosis of TB by quality ensured sputum smear microscopy.
3. Standardized short course anti TB treatment (SCC) given under direct and supportive observation (DOTS).
4. A regular uninterrupted supply of high quality anti TB drugs.
5. Standardized recording and reporting.

Question 9

Why did DOTS not work?

Answer 9

a. HIV
b. Drug-resistant TB
c. Some programs have < 85% cure rate
d. Patients do not adhere to DOT

Question 10

Types of Drug Resistant TB

Answer 10

MDR, XDR, TDR

Question 11

Implications of drug resistant TB?

Answer 11

Cost: anywhere from 260,000 to 554,000 dollars
Mortality: Only half of people with MDR were cured, only 1 in 5 receive treatment
Ethical: what to do with untreatable TB patients

Question 12

Syndemic

Answer 12

Disparity conditions that promote disease clustering, leads to enhanced disease transmission, progression

Question 13

HIV TB coinfection- challenges

Answer 13

• Increases risk of progression from latent to active TB diseases • Associated with atypical presentation and diagnostic delays
• Associated with worse treatment outcomes
HIV changes the presentation and outcome of TB
3. Antiretroviral therapy improves outcomes, but integrating TB and HIV care is challenging

Question 14

Strategies to control TB

Answer 14

High quality DOTS

2. Address MDR-TB and HIV/TB
3. Strengthen Primary Health programs
4. Engage all providers -> TB standards of care
5. Empower communities and people with TB
6. Enable and promote research -> operational research