A 36-Year-Old Female Drug Abuser Has an Abscess on Her

Multiple Choice

A 36-year-old female drug abuser has an abscess on her jaw where she lost a tooth from being struck in the face 2 weeks ago. She did not get medical help. You lance the lesion, express some lumpy material with difficulty, and send a swab of the organism to the lab for Gram stain, culture, and susceptibilities. The predominant organism in the Gram stain is a filamentous bacterium that is Gram positive, yet nothing grows in the lab. What is the most likely explanation for why it did not grow?

A) It is an obligate aerobe
B) It is microaerophilic
C) It is a facultative anaerobe
D) It is an obligate anaerobe
E) The lab did not grow it on the correct medium