Esmee Polmear died from rare lung condition

Esmee Polmear died in hospital after collapsing at school in July

A seven-year-old girl who collapsed at school died from a rare lung condition which affects about one in 10 million people, a post-mortem has revealed.

Esmee Polmear's parents said doctors saw her numerous times in the two years leading up to her death and were "disappointed" it was not diagnosed.

Esmee had pulmonary veno-occlusive disease - a rare condition that causes high blood pressure in the lungs.

The condition is "almost always fatal", the post-mortem concluded.

Esmee died at the Royal Cornwall Hospital in Truro after collapsing at Perranporth School on 1 July, despite doctors telling her parents "not to worry" about her health.

"When you see your daughter on the floor dead, it's not right... we couldn't function," said her father Mark Polmear.

An earlier post-mortem examination in July proved to be inconclusive.

Lynette and Mark Polmear said doctors saw her numerous times in the two years leading up to her death

In a letter from the coroner to the family, following the second post mortem, they were told "about one in 10 million people are affected by this disease" and it is "almost always fatal".

It added that those with the disease had an average life expectancy of two years.

Esmee had been complaining of breathlessness and had been seen at St Agnes Surgery on a number of occasions.

Her parents said she was referred to a paediatrician at the Royal Cornwall Hospital, where she was given a heart monitor for 24 hours.

People dressed as Mini Mouse, Snow White and Shrek when they attended Esmee's funeral

The results showed her heart to be normal and a follow-up appointment was cancelled, they said.

They took her to see a doctor at the surgery just weeks before she died, saying she had lost one stone in weight, but say they were told Esmee was "just anxious".

An inquest into Esmee's death is expected to be held in 2016.

The surgery and the Royal Cornwall Hospital Trust have declined to comment.