Crumlin Hospital has sought to shed more light on why it recently told the wrong patients they could be affected by a colonoscope contaminated with the potentially serious ESBL bug.

The hospital, it transpires, mixed up two scopes, both of which were contaminated, but the second scope was contaminated not by ESBL but by the Klebsiella bug, whose presence on the scope had no associated health risks, according to Crumlin. Eighteen patients exposed to this scope were checked in error for ESBL.

The HSE has now launched an investigation into why the 18 families were wrongly told their children had potentially been affected by ESBL as a result of having procedures done with one of the scopes.

It subsequently transpired that seven different patients exposed to the other scope but initially not contacted by the hospital had potentially been affected by the ESBL bug.

The hospital told irishhealth.com that the mix-up related to two colonoscopes, both of which were found to be contaminated earlier this month and were subsequently quarantined.

The hospital said the ESBL contamination was wrongly attributed to a second scope, which had traces of a different bug, Klebsiella, but there were no health risks attached to this contamination.

This led to the 18 patients being wrongly informed they potentially had ESBL contamination, when they were not at risk.

The hospital subsequently discovered that the wrong scope had been identified as carrying ESBL.

A hospital spokesman said the contamination of the scopes was likely to have been due to them not functioning properly, rather than their not being properly sterilised. He said contamination had remained on both scopes after sterilisation, which raised a 'red flag' of concern about them.

HSE Director General Tony O'Brien has strongly criticised the hospital for initially identifying the wrong scope and the wrong patients. The HSE is launching a probe into the hospital's handling of the issue.

The hospital confirmed the ESBL contamination on July 10. This bug usually does not cause subsequent infection but its presence can make infections very difficult to treat with antibiotics.

Meanwhile, Crumlin told the safety body HIQA in a quality improvement report in March that it was compliant with sterilisation and decontamination guidelines for medical equipment, it has emerged.

The hospital told HIQA at the time, in response to a previous hygiene inspection, that it had implemented a review of cleaning schedules for patient equipment in all identified non-compliant areas to ensure compliance with the guidelines. It said it had also reviewed practices to ensure that equipment was clean and ready for use.

However, it is unclear whether the equipment compliance referred to by Crumlin included the area of the hospital where colonoscopes are normally used, as only certain areas of the hospital were examined in the HIQA inspection the previous December.

HIQA, following a further inspection of Crumlin Hospital in March, ordered it to undertake an audit on the use of all invasive medical devices in order to ensure that infection was being effectively prevented.

The hospital has recently introduced new cleaning and disinfecting equipment for scopes.

Crumlin omnishambles raises major safety issues