A file on the circumstances of the girl's death is being prepared for the Irish Director of Public Prosecutions.
An inquest at Southwark, south London, on Wednesday, was told that Kelly Fitzgerald's body had multiple lacerations and bruises, suggesting she had been beaten with a belt. Scars on her buttocks indicated she had been burnt with a cigarette, and there was evidence that she had been denied food and water.
A post-mortem examination showed that Kelly, who weighed six stones - 25 per cent underweight for her age - died from blood poisoning stemming from a gangrenous wound.
The inquest was adjourned for reports on the case by Lambeth social services after the coroner, Sir Montague Levine, said there was 'ample evidence of abuse'.
Kelly's uncle, Garry Fitzgerald, told the inquest that she had been registered as at risk from abuse when she lived with her family in Lambeth.
Her parents returned to Ireland two years ago, but Kelly stayed in London with her grandparents, where she was 'a normal, healthy little girl'.
Last August, Kelly decided to go to live with her parents, who have five other children, but returned to England on 1 February, arriving at Stansted airport, Essex, in a wheelchair and semi- conscious.
Mr Fitzgerald, a social worker, said: 'I was in a state of shock when I saw her. She looked severely brain damaged, and had lost about 30 pounds.' She was taken to hospital, but never regained consciousness and died a few days later.
After the hearing, Mr Fitzgerald criticised Lambeth social services for not responding when he alerted them that Kelly was to rejoin her parents, despite being on the 'at risk' register.
But Lambeth Child Protection Service said its officials had alerted the Irish Western Health Board to the girl's risk status.
Brendan Howlin, the Irish health minister, said: 'We want to find out why a seemingly outgoing teenager could be abused in this way without coming to the attention of social services.'
But Mr Howlin added that the Irish DPP would have to decide whether there was a prima facie case for bringing criminal proceedings over Kelly's death.
Her parents, Desmond and Susan Fitzgerald, who did not attend the inquest, issued a statement through their solicitor, Charles Kelly, denying ill- treating her.
Mr Kelly said: 'The matter is sub judice, but my clients did not abuse or ill-treat their daughter, and they are satisfied they will be vindicated on that in due course.'
Last night the couple were understood to be travelling to London from Tonroe in Co Mayo, to attend the funeral of Mrs Fitzgerald's mother.