The HSE says it has known since February about a computer glitch which meant hundreds of women who underwent CervicalCheck screening were not given their results.
Around 800 women who had repeat HPV tests didn't receive their results due to an IT issue at the Quest Diagnostics lab in Virginia.
The Department of Health was only notified of the issue earlier this week.
The HSE says those affected should now have their results from their GP, or will be able to get them within the next day or so.
It comes as the HSE also confirmed that a number of other women caught up in the latest CervicalCheck controversy in addition to the 800 revealed yesterday.
It said investigations are being carried out at the highest level, to see if any more women are affected by the issue.
It centres around a computer glitch at Quest Diagnostics laboratories in Virginia in the USA
Yesterday it was revealed around 800 women who were having HPV tests rechecked, did not receive their results due to an IT glitch at the Quest Diagnostics Chantilly facility in Virginia.
It centred on tests carried out from late last year to June this year.
Today, the HSE confirmed they are also aware of "a very small number" of people affected outside of this recheck group and are following up on those cases as part of its' response.
In their statement, the HSE said: "We are also aware of a very small number of people affected outside of this recheck group and are following up on those cases as part of our response."
Clinical Director of the Women and Infants' Health Programme, Dr Peter Mc Kenna, said today the incident is being investigated at the highest level.
This includes investigating with Quest Diagnostics whether any more patients have been affected and more information is being urgently requested by the HSE and CervicalCheck.