Baby had seizures as a symptoms of ARX

A British baby has become the first in the world to die from a virtually unknown brain condition that rapidly shrank his brain.

Mother Karen Marshall-Rogers told how she was powerless to help as the condition ARX caused her son's brain to dramatically shrivel from the inside out.

Baby Seth died aged nine months just weeks after doctors made their diagnosis.

Baby Seth died from a very rare brain disorder, which caused the organ to shrivel
Karen, 26, from Aylesbury, Bucks, said: 'We were told he is the only child in the world to have that specific mutation, which caused his brain to shrink.

'He was a beautiful little boy and he has been taken away from us by this horrendous condition.'
Seth was admitted to his local hospital just after Christmas with constant fits that baffled doctors.
He was then tube-fed after he starting losing weight because he couldn't swallow.

The stumped medics then decided to transfer him to a special neurology unit at the John Radcliffe hospital in Oxford.

Karen and her catering manager husband Ben, 30, spent every day with their baby boy as he underwent tests and scans.

He was finally diagnosed with ARX in May this year and told he had just six weeks to live as his brain was shrinking so fast there would soon be nothing left.

Seth's condition deteriorated rapidly and he eventually died on June 16.

A normal brain scan (l) and a scan of Seth's brain that shrank from the inside out
Karen said: 'We were devastated of course but it was a relief to finally know what was wrong with Seth.

'We knew in February that he had a degenerative condition but just didn't know what it was. At least we could then ask questions.'

The condition - which only affects boys - is so rare that Karen and Ben couldn't even find anything out about it on the internet.

Dr Sandeep Jayawant cared for Seth when he was transferred to the special children's unit at the John Radcliffe hospital.

The consultant paediatric neurologist said he is preparing to publish a paper on the condition. Only two other children are known to have the condition in Japan.

Karen and Ben, who also have son Bailey, three, have set up a memorial fund in Seth's name.
They want to raise awareness of the virtually unknown condition - to ensure all hospitals test children for ARX (full name Aristaless Related Homeobox) if they have seizures.

Dr Jayawant added: 'From data we have seen there may be around five in 3.5million children with ARX. It is such a rare condition that not many people know about it.

'It is primarily a movement disorder and causes epilepsy-like seizures.'

The leading consultant said he would encourage all hospitals in the UK to screen kids for the condition.

'We are able to test for it and we are doing that at the John Radcliffe, but it is not a widespread policy,' he said.

'Hopefully with the knowledge from Seth's case more hospitals will begin to test for ARX.'