An inquiry into the infection with hepatitis C of a patient while undergoing dialysis at Dublin's Beaumont Hospital three years ago has been unable to determine how the patient became infected.
The investigation was ordered after the patient was discovered to have the virus during a routine screening test in August 2001. The patient, who had been attending the unit for dialysis three times a week, had tested negative for the virus the previous April.
Given the high prevalence of hepatitis C among dialysis patients in some countries, it was suspected and reported in the media at the time that the patient may have contracted the virus while being dialysed at Beaumont.
After a lengthy investigation, the inquiry into the patient's infection has now "been unable to identify an incident or event which may have led to transmission".
However, it established that on one particular date another patient with a similar strain of hepatitis C had used the same dialysis machine.
The newly-infected patient had not been dialysed elsewhere and had no other risk factors for contracting hepatitis C, a viral infection of the liver.
The as-yet unpublished report from the investigation team, headed by the hospital's consultant microbiologist Dr Edmond Smyth, states: "We have been unable to identify an incident or event which may have led to transmission."
It added: "It's possible that infection occurred on the one day when both patients were dialysed on the same machine.
"However, the procedures in place and the records maintained strongly suggest that this was unlikely.
"In addition, the time interval between the above and documented serocon version is extremely long with negative serology on 30/4/01, five months after the day in question."
Ultimately, the report is inconclusive, not ruling in or out the possibility that the patient picked up the infection in the dialysis unit.
A hospital spokesman said there had been 300,000 dialysis treatments at Beaumont since its dialysis unit opened in 1987 and this was the first case of hepatitis C infection to be investigated. This meant the prevalence of hepatitis C in the unit was one of the lowest in the world, he said.
Details of the inquiry team's report into the incident were reported in yesterday's Irish Medical News. The Irish Kidney Association said about a dozen people were suspected of having contracted hepatitis C while being dialysed in the State to date.