A baby boy was found dead after having starved for several days despite being under the care of at least nine doctors, social workers and health visitors.
The emaciated body of the 10-month-old, the son of an HIV-positive woman, was found in his family's flat in north-west London on March 8.
His 29-year-old mother was arrested on suspicion of child neglect but died two days later from a rare brain condition linked to her medical condition, the Daily Mail reported.
A post-mortem examination earlier this month has not yet fully established a cause of death for the baby boy and officers are waiting for further test results, Scotland Yard said.
But an internal management review by one of the health trusts involved, Central and North West London NHS Foundation, leaked to the Daily Mail, said: "Post-mortem results on the infant showed that he had no food in his gut at all and so had not eaten for several days at least. However, there is evidence of a long period of malnourishment."
A serious case review has been launched into the circumstances surrounding his death.
The boy, who was said to have had "massive" developmental difficulties, an underlying serious health condition and a history of being underweight, is reported to have been seen at least 15 times in the last six months by care professionals.
The agencies involved in the case are said to be two health care trusts, Westminster City Council social services and a consortium of London boroughs providing health visitors.
Westminster council said the baby boy and his three-year-old sister were not on the child protection register.
Terry Bamford, chairman of Westminster Local Safeguarding Children Board, said: "This is an extremely tragic case and our thoughts are with the surviving family members. The review will look into several aspects of this complex and challenging case, many of which are still unclear at this early stage."
