The HSE has admitted that an apology was only offered to the woman at the centre of abuse claims in the south east this week.
That is despite it informing the Public Accounts committee that it had already happened.
The body has said it was intended that this would happen last month - however no apology was in fact issued officially until a few days ago.
The junior health Minister has asked senior counsel Conor Dignam to investigate the handling of the abuse claims which date back to the early 1980's.
The head of the HSE is due before the PAC on Tuesday.