I heard an interesting talk by Dr Michael Miller last week on the ethics of screening for MDROs. Whilst we need to think carefully about the ethics of all medical procedures (great and small), I think the benefits to the individual and the population generally outweigh downsides for MDRO screening programmes.

There are some evidence-based set of criteria to consider when implementing screening programmes for any disease or condition from Public Health England. It is worth reviewing these criteria with MDRO screening programmes in mind. A couple of the criteria are not a good fit with most MDRO screening programmes:

• ‘All the cost-effective primary prevention interventions should have been implemented as far as practicable’. This suggests, prima facie, that we should ensure we have 100% compliance with hand hygiene before considering CPE screening!
• ‘There should be an effective intervention for patients identified through screening, with evidence that intervention at a pre-symptomatic phase leads to better outcomes for the screened individual compared with usual care.’ and ‘…where there is no prospect of benefit to the individual screened, then the screening programme shouldn’t be further considered.’ Whilst we know that MDRO carriers are more likely to develop MDRO infections than non-carriers, pre-symptomatic interventions are not always available. In the case of MRSA, decolonisation can be attempted. But this isn’t feasible for the likes of CPE.
• ‘There should be evidence from high quality randomised controlled trials that the screening programme is effective in reducing morbidity and mortality.’ Anybody know of an MDRO screening programme that fit this criterion? I don’t!
• ‘There should be evidence that the complete screening programme…is clinically, socially, and ethically acceptable to health professionals and the public’. I have heard some question the ethics of routine rectal sampling, particularly in some patient populations.
• ‘The benefits gained by individuals…should outweigh any harms for example from overdiagnosis, overtreatment, false positives, false reassurance, uncertain findings, and complications’. There is undoubtedly a degree of overdiagnosis and overtreatment associated with MDRO screening programmes. I can’t recall any data on this (please let me know if you can) but I am sure patients with known MDRO colonisation are far more likely to receive unindicted antibiotics “just in case”!
• ‘The opportunity cost of the screening programme…should be economically balanced in relation to expenditure…’. There’s not a lot of cost effectiveness analyses around MDRO screening: a high profile model on the cost-effectiveness of MRSA screening found that pretty much none of the options were cost-effective, whereas a recent model of CPE screening concluded that the programme was cost-beneficial in most scenarios. Clearly, a need for more data here.
• ‘There should be a plan for managing and monitoring the screening programme and an agreed set of quality assurance standards’. I don’t think this is the norm when establishing an MDRO screening programme, sadly!

All of the above should be taken with a pinch of salt because it’s only partially relevant to MDRO screening programmes: MDRO screening programmes result in potential benefits both for the individual (more rapid appropriate antibiotics if an infection develops) and the population (reduced transmission), whereas most screening programmes only result in potential benefits to the individual. However, some argue that we should move away from a ‘targeted’ (aka horizontal) approach to IPC, centred around screening and isolation, and focus on a ‘universal’ (aka horizontal) approach (e.g. optimising hand hygiene and disinfection standards for all). Clearly, nobody would argue that we shouldn’t optimise hand hygiene and disinfection standards for all, but I do think that a targeted approach is warranted for some organisms at least some of the time (for example, it would be a brave expert who would recommend not isolating a patient with symptomatic C. difficile infection)! Furthermore, I believe that MDRO screening programmes have the support of patients, provided they are explained in a language that patients can understand. I was involved in a study where we had a major problem with compliance with a rectal screening programme for CPE. Once the message to patients was changed from bug-focussed to patient-focussed (emphasing potential benefits to the individual and their peers), compliance with the programme increased dramatically.

We need more research on the effectiveness and cost-effectiveness of MDRO screening programmes. But I do think they should be pursued, at least in principle, as a cornerstone of IPC practice.

Image: Blue Diamond Gallery.