An acid-fast bacillus is recovered from a bronchial washing on ...

[RYAN BANYAN]

An acid-fast bacillus is recovered from a bronchial washing on Lowenstein-Jensen medium after 18 days at 35C with CO2. Initially the colonies are buff, raised, and rough when grown in the dark.
 
  After exposure to light, no change in pigmentation is noted. On examination at 10X magnification, the colonies reveal serpentine cording. Which of the following biochemical test reactions will confirm the identity of the most likely etiologic agent?
  A) Niacin and nitrate positive B) Niacin positive and nitrate negative
  C) Niacin negative and nitrate positive D) Niacin and nitrate negative

Question 2

Which of the following antibiotic classes acts on the organism's protein synthesis?
 
  A) Glycopeptides B) Beta-lactams C) Aminoglycosides D) Carbapenems

[billybob123]

Answer to Question 1

A

Answer to Question 2

C