I read a Controversies blog today, reflecting on a recent editorial suggesting that, because of frequent over-diagnosis, we should use quote marks every time we write “CAUTI” – and even use air quotes every time we say it! But why stop at CAUTI? Should we be talking about “CLABSI”, “CDI”, “SSI” and, well, any “HCAI” really?

I shared the “CAUTI” post with our epi group, which prompted much nerdy use of air quotes. At one point, I misspoke “CLABSI” for “CAUTI” and that got me to thinking that there’s probably as much over-designation and over-diagnosis in CLABSI as there is in CAUTI.

Part of the problem is in finding fairly sensitive and specific surveillance definitions that can be feasibly applied without reviewing each case in detail. In this scenario, there are bound to be cases where patients exhibit some of the signs and symptoms of an infection without actually being infected.

But the problem is more fundamental: even when cases are reviewed in detail, it can be unnervingly challenging to pin down whether or not a patient is infected. Or, even more subtly, whether you need to do anything about it. In the case of UTI, an interesting recent study suggested that most uncomplicated UTIs resolved without anti-infective treatment. In the case of CLABSI, we commonly use “BSI” to refer to both bacteraemia (which may not result from an infection) and an actual BSI. In the case of SSI, is a surgical wound from which bacteria are cultured infected? Most surveillance definitions would say yes, but surgeons would often say no. And where is the line between colonisation with an MDRO and infection? I have recently been involved in a detailed review of a series of patients to determine which were infected and which were colonised only. Despite extensive reviews by multiple docs, there was still some uncertainty about the line between infection and colonisation in some cases.

Whenever I hear a clinical case presented, I am struck by the huge amount of uncertainty involved. Most people unacquainted with medicine assume that you go to the doctor and they tell you what is wrong, definitively. But in the world of infection (and all else besides), reaching a diagnosis isn’t as simple as that and in many cases you simply don’t know. This means that the message to a patient is often “you may have an infection”; this degree of uncertainty is unsatisfactory to all parties, but something we have to live with. Perhaps it would be helpful to reflect this uncertainty in the liberal use of “HCAI”!

Image: Wikipedia.