Annalise Luffingham, known as Annie, was taken to the children’s A&E at Croydon University Hospital after suffering a headache, eye pain, dizziness, vomiting and a high fever on February 11 last year.
She was at hospital for nearly seven hours before being given antibiotics, after medical staff failed to recognise the danger she was in.
Annie, from Addiscombe, who was a pupil at Royal Russell School in Shirley, had a cardiac arrest just over an hour after being given antibiotics and died the following day.
Her parents, Tracey Shephard, 49, and David Luffingham, 54, hired medical negligence lawyers at Irwin Mitchell to investigate their daughter’s care and have called for “lessons to be learned” from her death.
The inquest heard that an initial assessment for sepsis, which would have indicated an infection, was not completed properly so Annie was not given antibiotics earlier.
Also, despite suffering an increased respiratory rate, she was not assessed by a paediatric consultant for three hours and her deteriorating condition was not acted upon.
Kent assistant coroner Sonia Hayes found Annie died of natural causes contributed to by neglect.
Croydon Health Services NHS Trust, which runs the hospital, has admitted liability for the death, the family’s lawyers say.
Elaine Clancy, chief nurse at Croydon Health Services NHS Trust said: “We are committed to continuing to learn from this tragic incident to further improve our care.”