The Journal of Hospital Infection have published a welcome special issue on multidrug-resistant Gram-negative bacteria. The collection includes some updates on epidemiology, staff carriage (again!), clinical microbiology, and patient perspectives on CPE, and is well worth a read.
A brave study from the Palmore/Frank group at NIH has opened the Pandora’s Box that is screening staff for MDROs, and, I’m delighted to say, firmly closed it with their findings! Only 3% of staff carried ESBLs, one carried a CPE, and none carried VRE, and this despite extensive contact with MDRO patients for many of the staff sampled!
BMC Medicine have recently published a study from researchers in Oxford, PHE, and Manchester illuminating the importance of referral networks in the transmission of CPE. The bottom line is that regional referral networks seem to be the most important driver of CPE spread, such that a small CPE problem close to home is more of a threat than a larger CPE problem in a distant referral network!
Many guidelines now recommend screening some patients on admission for carriage of CPE. However, very few cost-effectiveness analyses have been performed. A Canadian group have just published a modelling study with a tantalising conclusion: universal admission screening for CPE is likely to be cost-effective, and may even be cost-saving!
I am currently involved in some research that requires a clear distinction between CPE (i.e. Enterobacteriaceae that produce a carbapenemase) and non-carbapenemase-producing CRE. Since ‘non-carbapenemease-producing carbapenem-resistant Enterobacteriaceae’ is a bit of a mouthful, I need to come up with some sort of acronym. I would appreciate your thoughts on the scheme set out below:
You can read more thoughts on acronyms for carbapenem-resistant bacteria in a previous post here.
A case of pan-drug resistant NDM-producing K. pneumoniae CPE that resulted in a fatal infection in a US woman has prompted a lot of coverage and discussion on both sides of the Atlantic. Although this report is concerning, not least because the patient succumbed to the infection, this is hardly a new scenario. There are parts of the world where pan-drug resistant CPE are commonplace and have been for years (for example parts of India, the likely country of origin of the organism in this case). Before getting to the case report in detail, let’s take a moment to review this case series from India, published in 2014. 13 patients with pan-drug resistant Gram-negative bacteria (7 of whom were infected with K. pneumoniae, 4 of these 7 died) were reported in a specialist cancer treatment centre over 18 months over 2012/13. This evidence, from half a decade ago, shows that pan-drug resistant CPE is by no means a new phenomenon! Continue reading
The risk of interspecies transmission of carbapenemase genes is a real concern. We can barely get our heads around many different types of carbapenemase in a whole host of Gram-negative bacteria (compare the relative simplicity of methicillin resistance in S. aureus: a single gene, in a single species). Throw in interspecies horizontal transmission of carbapenemases and things get really tricky! Do we implement different control strategies to try to interrupt the transmission of carbapenemases (in contrast to the organisms themselves)? Could you have a multispecies outbreak of a carbapenemase on your hands and not even realise it?