Parents of children wrongly diagnosed with epilepsy say their agony is being made worse by the delay of a report into the actions of a hospital specialist.
Consultant paediatrician Dr Andrew Holton has been suspended from Leicester Royal Infirmary on full pay since June 2001.
Families have been told the inquiry has been held up because a computer crashed.
Carole Ryan's teenage son John was wrongly treated for epilepsy for three years.
'Total zombie'
"I think it is another sign of the incompetence of the hospital in dealing with the whole situation with Dr Holton," she said.
"We don't know what's happening and we don't know when the report is coming out - two days before Christmas and we have the whole thing in our face again."
An investigation was launched into Dr Holton's treatment of nearly 2,000 children with epilepsy.
It has been discovered that he gave the wrong treatment or wrongly diagnosed more than a 150 children.
Mrs Ryan said: "My son was taking three different drugs at the same time and on huge doses of each of them.
"He was a total zombie, sleeping for about 15 hours a day and at school he couldn't concentrate at all and was achieving nothing at all."
The letter to parents apologises for the inquiry delay, saying important data was lost in the crash.
Hospital managers say they are confident all the information has been retrieved.
The General Medical Council has changed the details of Dr Holton's registration, effectively stopping him from working while investigations are carried out.
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