Superbug linked to eight patient deaths in Limerick hospitals

CPE gut bug ‘not directly responsible’ for any of 73 patient deaths reviewed in hospitals

University of Limerick Hospitals Group has admitted to “shortcomings” in communications with the coroner and the documentation it kept on patients after a report found a highly drug resistant superbug was linked to the deaths of eight patients.

The group says these shortcomings, relating to how next-of-kin are communicated with after a patient has died and the notifications sent to the coroner about hospital-acquired infections, are “being improved upon”.

A review of 73 patient deaths in Limerick hospitals between 2009 and May last year found none had died directly of the CPE superbug but it was “an associative factor” in eight deaths.

These eight patients had significant underlying health problems, according to the 60-page report published on Tuesday.


The findings have been communicated to the next-of-kin of the patients concerned and a helpline has been established.

The investigation was carried out by UK microbiologist Dr Robert Spencer after a whistleblower provided details of the patient deaths to the local coroner. On foot of the 60-page report, staff have been reminded of the requirement to notify the coroner of healthcare infections associated with patient deaths.

Carbapenemase Producing Enterobacteriaceae (CPE) is the newest in a long line of bacteria that are extremely difficult to kill with antibiotics.

Of all the superbugs, CPE is the most resistant to antibiotics. It lives harmlessly in the gut in healthy people but can be lethal if it gets into the bloodstream or urine. It poses a particular risk to older people and those with reduced immune system function.

The first case of CPE in Ireland was isolated in University Hospital Limerick (UHL) in 2009 and the first outbreak in an Irish hospital occurred in UHL in 2011.

The bug has since been found in many other hospitals, and is a growing cause of concern within the health system.


The group claimed on Tuesday that preliminary work was already underway on an internal investigation by the time it was informed of the protected disclosure alleging “wrongdoing” that was made by the whistleblower to the local coroner last year.

Commenting on the review findings, prof Paul Burke, chief clinical director, UL Hospitals Group, said: " It is the conclusion of the report that CPE was an associated factor in the deaths of eight patients. All these patients also had other significant medical problems, and CPE was only one of a number of factors contributing to their deaths."

“Differing opinions will always exist between clinicians as to the relative contributions of different conditions to a patient’s death in those who suffer from multiple medical problems. We believe our conclusions are reasonable,” said prof Burke.

CPE has been detected in 196 patients in Limerick between 2009 and 2017, but in most cases patients were colonised with the bug, meaning it was living harmlessly in their gut. There have been three cases of CPE bloodstream infection - which has a mortality rate of up to 50 per cent - but none since June 2015. Nationally, there are been 50 such episodes of bloodstream infection since 2014.

The internal and external investigations came to different conclusion in relation to the number of CPE-related cases but the final figure of eight deaths in which the bug was a contributory factor was arrived at following a reconciliation exercise.

‘Complex history’

Speaking at a press conference at UHL, Dr Spencer said all of the cases examined had “a very complex medical history”. He said he found it “extremely difficult” to “tease out” the actual cause of death.

“It’s very very difficult to say which is the cause of death. That’s why, in my report, I talk about ‘an association’ or ‘a contribution’ to death, and that’s why I suppose you could say it’s somewhat woolly; it’s not definitive.”

When asked later to clarify whether he was referring to the actual findings of the report or the possible cause of death of the patients, he replied: “Both in actual fact.”

“It’s a very mixed picture. So, sometimes you get a death certificate and if it just has one (cause) . . . but often they don’t, and then you try and put that all together and say, ‘well, actually, what did they die of?’.”

“It’s unfortunate they did die, but whether (or not) CPE was the main cause, I find very difficult to interpret.”

Professor Martin Cormican, national clinical lead on anti-microbial resistance, stressed there was no major risk from CPE to people who are otherwise well and not in a hospital setting. The threat is posed to patients with low immune systems in hospitals or nursing homes.

Cormican described UHL “ as safe a hospital as any other”.

“Nobody has found the perfect solution to it. Nationally we have a lot to do.”

An expert group has been set up to monitor the situation nationally.

Hand hygiene is the biggest deterrent to CPE.