The UK guidelines for the prevention and control of multidrug-resistant Gram-negative bacteria (MDR-GNB) are published this week. It’s useful that the publication of these guidelines coincides with Antibiotic Awareness Week because MDR-GNB are brining us ever closer to the end of antibiotics. Although the guidelines don’t cover the treatment of MDR-GNB (this will be addressed in a forthcoming guideline), these highly resistant MDR-GNB leave few therapeutic options. Even when they remain susceptible to some antibiotics, these antibiotics are not front-line antibiotics for a reason (including poor tissue penetration and side effects). Furthermore, we are already seeing resistance to last-line (aka end of the golden-antibiotic-road) antibiotics e.g. colistin. Therefore, the old adage that ‘prevention is better than cure’ has never been so true!

I recently reviewed the available EU guidelines for the prevention and control of MDR-GNB. It’s a shame that these UK guidelines were not published in time to be included in this comparison because, along with the ESCMID guidelines, they are the only guidelines that attempt to evidence-grade recommendations. Since I was a member of the guideline writing group, I can personally affirm that try to evidence-grade these guidelines was the stuff of nightmares due to the wholly inadequate evidence base. Pretty much all recommendations were ‘Conditional’ (where the ‘desirable consequences probably outweigh undesirable consequences’); the few recommendations that were ‘Strong’ (where the ‘Desirable consequences clearly outweigh undesirable consequences’) were mainly on the strength of expert opinion than on the evidence base in most case! Nonetheless, it was a useful exercise to evidence-grade the recommendations, to highlight the limitations of the evidence base if nothing else.

One of the most useful parts of the guideline is a “Quick Reference” table that provides guidance on how the recommendations should be applied in respect of the various MDR-GNB. (You could of course argue that a table spanning 3 pages is hardly quick reference – but I hope it’s more accessible than a list of recommendations!). It was a real challenge to decide what these organism-groups should be. In the end, we decided to go for three columns: Resistant Enterobacteriaceae, A. baumannii and P. aeruginosa, but we very nearly had a separate column for CPE. This illustrates how difficult it is to write a guideline for ‘MDR-GNB’, since this is such a rich microbial cauldron of bacteria and associated resistance mechanisms. An earlier table in the guidelines was designed to lay-out the gulf in epidemiology between the various MDR-GNB, and justify the need for this “Quick Reference” table, stratified by organism-group.

The most controversial areas emerging from my review of EU guidelines were around patient screening and environmental decontamination.

• Patient screening: These UK guidelines recommend that active surveillance (rather than passive surveillance) should be performed on high risk units, risk-factor based screening should be performed on all patients for CPE (in line with the PHE Toolkit), screening for A. baumannii and P. aeruginosa should be restricted to outbreaks (outside of high risk settings), and contact tracing should be performed in the event of secondary cases. I believe these to be a fair reflection of the current evidence – although you could certainly argue about some of these recommendations (not least the evidence available to support the PHE Toolkit approach to CPE).
• Environmental decontamination: The UK guidelines are more forthright with their recommendations around environmental cleaning and disinfection than other EU guidelines, making a positive recommendation for terminal disinfection using bleach and consideration of hydrogen peroxide vapour as an adjunctive measure. There are also some useful recommendations around managing the potential water reservoirs for P. aeruginosa.

As always, it’s important to note that guidelines are not policy – and must be applied thoughtfully to develop an approach to controlling the spread of MDR-GNB that is informed by local epidemiology. We can’t rely on antibiotics for much longer as the “get out of jail free card” for when infection prevention and control fails. So I do hope these guidelines will prove useful in assisting the development of effective policies to prevent the spread of these challenging organisms.

Image: Wikipedia.