Microbiology - chapter 15 - Acid-Fast Bacteria

Question 0

acic-fast bacteria stain ?

Answer 0

Red. They stain red. That is what they do. They stain red.

Question 1

Two really famous mycobacteria would be?

Answer 1

1 Mycobacterium tuberculosis which causes tuberculosis.

2 Mycobacterium leprae which causes leprosy.

Question 2

What is the one class of lipids that only acid-fast organisms have, and that is involved in mycobacterial virulence?

Answer 2

Mycosides. Mycolic acid is a large fatty acid. It is bound to a carbohydrate making a mycosides. These mycosides are connected by Cord factors. The Cord factor is only found in the virulent strains of Mycobacterium and results in parallel growth of the Mycobacteria.

Question 3

Ghon focus vs Ghon complex?

Answer 3

A calcified tubercle in the middle or lower lung zone is called a Ghon focus. A Ghon focus accopanied by involvement of the perihilar lymph nodes = Ghon complex.

Question 4

1 Risk of tubercluosis reactivation in all persons?

2 Risk of tuberculosis reactivation in HIV infected?

Answer 4

1 10% lifetime risk

2 10% per year

Question 5

Most common site of reactivation tuberculosis?

Answer 5

Pulmonary tuberculosis

Question 6

Most common extrapulmonary manifestation of tuberculosis?

Answer 6

Lymph node infection. Usually cervical lymph nodes