A hospital is investigating an incident in which a patient's only healthy kidney was removed instead of the diseased one.

The incident happened at Prince Philip Hospital in Llanelli on Monday.

The patient, a 69-year-old man from the town, was transferred to Morriston Hospital in Swansea where he is critically ill.

Mike Jones, the Chief Executive of the Carmarthenshire NHS Trust, said a full investigation was being carried out.

"Our thoughts and feelings are with the patient and his family - and we are also concerned for the staff involved who are extremely distressed," said Mr Jones.

"There are safeguards in place and this hospital has a very good record in clinical risk management.

'Thorough and open' investigation

"We simply don't understand the reason why this happened."

The surgical team involved in the incident has been told not to carry out any similar operations until the internal inquiry has been completed.

"The surgeon involved has been suspended from his normal duties and has been restricted to minor 'day-case' surgery," said Mr Jones.

"We hope the community can remain confident in our service. We are anxious to complete a thorough and open investigation and we will apply the lessons in full."

National Assembly Health Secretary Jane Hutt said she was "devastated" to hear about the case.

"This causes me extreme concern. I have called for an urgent report from the Trust and I have asked them to keep me fully informed of their investigations," said Ms Hutt.

"I have been assured that the Trust is taking immediate and appropriate action and I will be making a statement on the case to the Health and Social Services Committee on Thursday."

Llanelli Assembly Member Helen Mary-Jones said she was appalled by the incident.

'One-off incident'

"It is absolutely devastating. It is very difficult to understand how such a terrible mistake can happen in this day and age," said Ms Jones.

"One can only imagine how the patient and his family are feeling at the moment - but it has to be emphasised that this is very much a one-off incident in the history of a hospital that has served the people of Llanelli very, very well."

A person needs at least one functioning kidney to be able to live without constant medical treatment.

A kidney specialist has told the BBC that the 69-year-old man will require require regular dialysis to stay alive.

He will also face severe restrictions on food and drink - and in the long term his only hope of regaining a normal life could be a kidney transplant operation.