At children's parties, four-year-old Annie Jones furtively scans the room to make sure none of her friends are watching her.

She will try to swallow a dollop of blancmange or maybe a tiny scoop of jelly but she's only doing it to appear normal.

Once away from other children and their parents she'll perform the pathetic ritual her frail body is all too used to - she'll throw up the paltry amount of food she has managed to swallow.

Annie suffers from infantile anorexia, which, unlike its better-known adult version, has nothing to do with imitating the stick-thin models of glossy magazines.

Annie rarely gets hungry and, on the few occasions her stomach tells her it's dinner time, merely bringing the food up to her mouth is enough to make her gag.

Dismissive doctors have told her mother Lisa to persuade her to eat by offering rewards. But Annie's food phobia appears to be far more deep-seated than that.

She has never been able to adjust to the transition to solid foods from the time she was just over a year old.

It is a purely psychological problem - a mental block - that can only be tackled by intensive treatment not yet available in the UK because most doctors do not recognise the condition in one so young.

That is why Lisa is now trying to save up the £80,000 needed for an eight-week course at a specialist centre in Baltimore, near Washington, in the US.

Without it, experts say, Annie will reach the age of six - when eating habits are ingrained for life - with little hope of a cure.

Lisa explains how Annie has survived for so long without solids. "She has a gastro tube inserted in her stomach which is attached to a drip-like machine.

"Every night it pumps 500 millilitres of special feed into her stomach at the rate of 50 millilitres an hour. That's enough to keep her going for the rest of the day. Apart from that, she might have the occasional sip of water or juice."

If the machine is stopped, like when she was recently treated in hospital for tonsillitis, she can lose as much as eight pounds in a week. When Annie's body only weighs two stone in the first place, her reliance on the machine is obviously total.

As well as the uncomfortable nights attached to a drip, Annie faces day-to-day miseries that are unthinkable for other children.

"Other children, parents and even teachers look at Annie when she's at school and think she's a normal, healthy child," says Lisa.

"She strains all day to make an effort to join in with other kids and tries to force food down her neck to appease the others. But when she gets home, she is absolutely exhausted."

It is not known exactly why Annie developed her eating disorder but the Kennedy Krieger Institute in Baltimore claims to have the cure.

They claim an 86 per cent success rate in curing under-eights of a condition that many British paediatricians say can't really exist.

The centre's paediatric feeding disorders programme is an intensive six to eight-week treatment that aims to unlock the psychological block put on eating by the child.

Its team of psychologists, psychiatrists, dieticians and speech therapists will, if Lisa can raise the necessary funds, strive to have Annie eating three square meals a day by the end of the programme.

Currently in the throes of a fund-raising drive, Lisa and her family and friends are determined to meet the costs.

She says: "It's a phenomenal amount of money to have to raise but the consequences of not doing so are pretty bad. Doctors say if she gets to the age of six and there's still no change, her eating habits are pretty much set for life.

"If she isn't cured by the time she's 16 she will then have the legal right to refuse her feeding tube. It is that thought that spurs us on to somehow get to Baltimore."

Report by Adrian Worsley