Tuberculosis

Question 1

Has Tb been around for a long time? Why?

Answer 1

Yes- for 5,000 years! It’s adapted to infect humans

Question 2

Tb was on the way to eradication until what disease became more prevalent?

Answer 2

AIDS

Question 3

What kind of Tb is a public health nightmare?

Answer 3

Multidrug resistant and extreme drug resistant Tb

Question 4

Do mycobacterium gram stain well?

Answer 4

No

Question 5

What kind of stain can you visualize them with?

Answer 5

Acid-fast

Question 6

Are mycobacterium slow growing or fast growing?

Answer 6

Slow growing

Question 7

What are the steps of the Acid-Fast stain?

Answer 7

1) Cover with carbofuchsin and steam
2) Decolorize with acid-alcohol
3) Rinse with water
4) Counterstain with methylene blue
5) Rinse and examine

Question 8

How do you know if a bacterium is acid-fast?

Answer 8

They hold the carbofuschin during the rinse

Question 9

How is Tb transmitted into the body?

Answer 9

Inhalation

Question 10

Where does Tb spread and by what route?

Answer 10

Lymph nodes, kkidneys, bones, CNS all by blood

GI tract by swallowing infected sputum

Question 11

How does an immunocompetent individual react when infected with Tb?

Answer 11

They raise a strong CMI response and can hold infection latent for decades

Question 12

Why does Tb reactivate?

Answer 12

Immunosenescene or immunosuppression

Question 13

Do macrophages spread or clear Tb?

Answer 13

Both!
Naïve macrophages spread the intracellular infection
Activated macrophages clear it

Question 14

What is the role of CD8 cells?

Answer 14

To kill infected macrophages and establish caseating granulomas in which the infection is contained

Question 15

What is the role of TNF-alpha?

Answer 15

Important for containment of infection

Question 16

How does classic pulmonary Tb present?

Answer 16

Cough, weight loss, fever, night sweats, hemoptysis, chest pain

Question 17

What tests should you run if you suspect someone has Tb?

Answer 17

Check sputum and get Chest Xray

Question 18

What are some extrapulmonary manifestations and tests to diagnose in those regions?

Answer 18

Scrofula- fine needle aspirate
GU- IV urography, urine culture
CNS- MRI, spinal tap
Skeletal- MRI, joint fluid culture
GI- xray, abdominal CT
Miliary- chest xray, with bright spotlight, lateral xray, chest CT

Question 19

Is pediatric Tb recently acquired or not?

Answer 19

Recently acquired (no time for latency)- look for source

Question 20

What should you watch for with pediatric TB?

Answer 20

Miliary Tb and meningitis

Question 21

Where do you culture from with pediatric Tb?

Answer 21

Gastric Lavage

Question 22

First step is to determine exposure- how do you do this?

Answer 22

With TST and/or IGRA

Question 23

As soon as cultures grow, what should you do?

Answer 23

Antibiotic resistance testing

Question 24

Treatment plan for Tb

Answer 24

Directly observed therapy with 4 plus drug course featuring isoniazid and isolate patient for first two weeks

Question 25

Why is the BCG vaccine used abroad and not here?

Answer 25

the live-attenuated vaccine is not cost-effective and can create false positive TST

Question 26

What are the most effective factors in reducing incidence of Tb?

Answer 26

Good diet and housing

Question 27

Are latent cases of Tb contagious?

Answer 27

No