11 hours ago
SA researchers expand baby heel-prick screening to help find rare conditions
When Max was three days old, he was diagnosed with a rare and life-changing condition called phenylketonuria, commonly known as PKU, through a newborn blood screening test.
The condition is one of more than 30 which can currently be detected in newborns through heel-prick blood samples to help identify and treat serious health conditions early.
Now, researchers in South Australia are working to expand the screening program to detect more than 600 genetic conditions.
PKU is an inherited blood disorder which can affect how the body processes protein and can eventually lead to serious health problems if left untreated.
"[It's] actually the condition that started the whole newborn screening program in the 1960s," explained South Australian researcher Professor Karin Kassahn.
"It's one of the metabolic conditions where the body can't process protein, phenylalanine in particular [which is] a certain amino acid, in the way it usually would … so by picking this up at birth, then the diet can be modified."
The heel-prick test method was developed by American microbiologist, Dr Robert Guthrie, whose niece was diagnosed with PKU at 13 months — too late to prevent early brain damage.
Since 1960, the program has been rolled out across much of the world as a routine test for newborns — and expanded to be able to accurately and quickly detect more than 30 conditions.
Twins, Max and Blake, underwent the screening as newborns.
Their parents, Hannah and Robert Macbeth, had no idea PKU existed when Max was first diagnosed.
"We'd never heard of it," Ms Macbeth said.
"We kind of cried about it until it kind of realistically hit us and we went, 'You know what, we can manage this. We've caught it early'."
Mr Macbeth said he was worried his son would have to follow a restricted diet for life.
"We're quite a barbecuing family so we love our meats and that sort of thing and entertaining," he said.
Thanks to early detection and intervention, Max's protein levels are closely monitored with weekly at-home prick tests, and he uses a medication to help lower his blood phenylalanine levels.
"We're very lucky," Ms Macbeth said.
"We could have been in all sorts of dramas for him because it can be pretty serious if left undiagnosed."
Untreated, PKU can lead to irreversible brain damage and intellectual disability, neurological conditions such as seizures and tremors, and problems with behaviour, emotions, development and health.
But for now, things are looking positive.
"He'll live a relatively normal life, he might just be a bit different with food at school and stuff," Ms Macbeth said.
"It's just managing it and it's quite easy at the moment … he's a happy little soul," Mr Macbeth added.
The couple said they thought expanding the testing program would be "brilliant".
"If we can do testing that picks up these things when they're little and there are things we can put in place to help reduce [the risk of] something happening in the long run or causing a bigger issue, then we would be mad not to do it," Ms Macbeth said.
Professor Kassahn is the principal investigator on the NewbornsInSA study which is combining genomics and metabolomics in a bid to detect more treatable conditions, earlier.
"Many of the conditions we screen for are rare, so individually people will probably not have heard of many of them — cystic fibrosis and PKU are probably the more familiar ones, but collectively they actually constitute quite a significant health burden," she said.
"They are the primary cause of childhood admissions to hospital and also ongoing health problems.
"Early detection allows early intervention and treatment, and just as the current program has really saved thousands of lives, we're hoping by expanding on that program … we can make a difference to the health outcomes for these babies."
The researchers are looking for conditions including immune deficiencies, conditions of metabolic dysregulation, congenital deafness, and neurological conditions.
Professor Kassahn said the study collaboration between SA Pathology, the Women's and Children's Hospital and the University of Adelaide was "well underway" with 250 families already enrolled, out of their target of 1,000.
The team has already made some significant findings — with early intervention now in place for those families to help treat or manage their rare diagnoses.
"We've issued five of what we call a 'high chance report' and those would have otherwise been undetected," she explained.
"Those families are being managed through the clinical teams at the Women's and Children's Hospital."
She said eligible families are still able to take part in the study with enrolment via the NewbornsInSA website.
