Stenotrophomonas maltophilia is commonly treated with TMP-SMX or levofloxacin and is resistant to which class of antibiotics?

Prepare for the CAMLPR Microbiology Test. Utilize flashcards and engaging multiple-choice questions, each equipped with descriptions and explanations. Ready yourself for an excellent performance!

Stenotrophomonas maltophilia has intrinsic resistance to a broad range of beta-lactam antibiotics because it produces two beta-lactamases (L1 metallo-beta-lactamase and L2 cephalosporinase) that neutralize many penicillins, cephalosporins, and even carbapenems. This strong resistance to beta-lactams is why the organism is typically treated with non–beta-lactam options such as TMP-SMX or levofloxacin. When a question asks which class of antibiotics the organism is resistant to, the key point to recall is its robust beta-lactam resistance, driven by those enzymes. The answer choice that references the organism itself semantically points to this resistance pattern, highlighting the characteristic of Stenotrophomonas maltophilia rather than naming a drug or another organism.