Myobacterium II

Question 1

Causes chronic pulmonary disease in adults with underlying lung disease (COPD, bronchiectasis)

-Grows best at 42C, found in hot water systems

Answer 1

M. xenopi

Question 2

Causes a rare, extrapulmonary disease in immunocompromised

Answer 2

M. xenopi

Question 3

M. xenopi is classified as a

-Biochemical/molecular ID

Answer 3

Scotochromogen

Question 4

Comprised of three dominant species: M. avium, M. intracellular, M. paratuberculosis

Answer 4

Mycobacterium avium Complex (MAC)

Question 5

What is the most commonly isolated species of MAC?

Answer 5

Mycobacterium spp.

Question 6

MAC is usually classified as

Answer 6

Non-chromogenic

Question 7

Important pathogen in immunocompromised (disseminated disease) AND immunocompetent hosts (pulmonary infection, lymphadentitis)

Answer 7

Myobacterium spp.

Question 8

Important (and sometimes difficult) to distinguish disease vs contamination or colonization in respiratory specimens

Answer 8

Mycobacterium avium Complex (MAC)

Question 9

Seen in post-traumatic, post-surgical, post-injection wound infections

Answer 9

Rapid growing mycobacteria (RGM)

Question 10

Rapid growing mycobacteria (RGM) cause

Answer 10

Chronic pulmonary infections

Question 11

Short, non-branching AFB in clusters, appear as GPR on Gram stain

-Arylsulfatase positive

Answer 11

RGM

Question 12

Often drug resistant, difficult to treat –> species level ID and antibiotic susceptibility tests are important

Answer 12

RGM

Question 13

RGM are classically distinguished biochemically by

Answer 13

Iron uptake, salt tolerance, and nitrite reduction

Question 14

Cannot be cultivated in vitro (armadillo animal model)

Answer 14

M. Leprae

Question 15

Spread from person-person, most likely via nasal secretions

Answer 15

M. Leprae

Question 16

M. Leprae causes single, multiple or widespread anaesthetic skin lesions. It is comprised of which two types?

Answer 16

Lepromatous or Tuberculoid