Wednesday, February 8, 2012

In Hospital C. difficile Transmission? Not so much.

There is an important paper in PLoS Medicine by Sarah Walker et al. in the UK that measured the proportion of C. diff cases in hospitalized patients that were acquired during their index hospital stay.  The results are pretty surprising. Using MLST, only ~25% of cases could be linked to inpatient transmission, ranging from 37% in renal/transplant down to 6% in specialist surgery.  Additionally, many of the C. difficile cases linked to in-hospital transmission manifest soon after the index case appeared clinically. In the accompanying editorial, Harbarth and Samore suggest that this means "the hospital environment was not, as has previously been claimed, a long-lasting reservoir for this pathogen."


1) Walker AS, et al PLoS Medicine February 2012
2) Harbarth S and Samore MH et al. PLoS Medicine (Editorial)


  1. Does this support the idea that C diff is hiding in the gut and then grows rapidly in some people who receive antibiotics? In this way of looking it, antibiotics kill off the usual gut flora that otherwise keeps the C diff at a low density that doesn't cause symptoms. So do the data support the idea that pre-existing gut flora C diff grow to cause illness?

  2. I think it does support that C. diff are brought in and appear via the mechanism you describe. The editorial does point out some issues with the study methods that could result in underestimating the proportion of cases secondary to in-hospital transmission....more studies needed.