Detecting antibiotic resistance is hard!

Eli linked me to this recent Nature commentary on the limitations of current screening tests for certain antibiotic resistant gram-negatives (those that carry carbapenemases). Because the resistance mechanisms for gram-negative bacteria are so complex and varied, resistance detection in the clinical microbiology laboratory has become a huge challenge. Furthermore, even if tests perform well to detect a specific single mechanism of resistance, what about bugs that use combinations of mechanisms? Consider how complicated it turned out to be to refine molecular methods for that comparatively simple organism, MRSA....emergence of empty cassette variants that result in false positives, divergent mecA genes that result in false negatives, and on and on we will go.  Multiply that complexity by a thousand fold for gram-negatives.


What this means is that every clinical microbiology laboratory needs a smart, well-trained clinical microbiologist--to optimize testing strategies, to understand the limitations of currently available methods, and to anticipate and detect problems with shiny new methods.  As the authors of the Nature commentary point out, too many hospitals are trying to cut costs in their microbiology laboratories, including being unwilling to staff them appropriately.  I was asked to talk at SHEA on molecular testing and infection prevention, and covered some of these issues (see below).
SHEA 2012 Diekema

Comments

Most Read Posts (Last 30 Days)