Burkholderia cepacia is intrinsically resistant to:
**Core Concept**
Burkholderia cepacia is a gram-negative, non-motile bacterium that belongs to the Pseudomonadaceae family. It exhibits intrinsic resistance to multiple antibiotics due to its unique cell envelope structure and efflux pump mechanisms. This resistance is a significant concern in clinical settings, particularly in patients with cystic fibrosis.
**Why the Correct Answer is Right**
Burkholderia cepacia's intrinsic resistance is primarily attributed to its ability to efflux antibiotics out of the cell using efflux pumps, such as the MexXY-OprM efflux system. Additionally, its outer membrane contains lipopolysaccharides that provide a barrier against antibiotic penetration. The bacterium's cell envelope also lacks porin channels, further limiting antibiotic entry. These mechanisms contribute to its resistance against a wide range of antibiotics, including carbapenems.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as Burkholderia cepacia is not inherently resistant to aminoglycosides, such as gentamicin, which can still be effective against it.
**Option B:** This option is incorrect as Burkholderia cepacia is not specifically resistant to quinolones, such as ciprofloxacin, although it may exhibit some resistance due to efflux pumps.
**Option C:** This option is incorrect as Burkholderia cepacia is not uniquely resistant to polymyxins, such as colistin, which can still be used as a last resort in treatment.
**Clinical Pearl / High-Yield Fact**
In clinical practice, Burkholderia cepacia infections are often associated with outbreaks in healthcare settings, highlighting the importance of infection control measures to prevent the spread of this resistant organism.
**Correct Answer:** D.