New fast work in saving infant livesLocal | Stella Wong 15 May 2019
Hong Kong Children's Hospital is providing a rapid screening test that will allow doctors to start moving on targeted treatments for newborns suffering from inborn metabolic diseases within one or two days rather than having to wait for full results.
Such genetic diseases are rare and can cause functional disorders and inhibit naturally occurring processes.
The hospital has been providing tests since the end of last year, covering 24 common metabolic diseases. Two more diseases will be added to the action list in October.
A dried blood spot metabolic test helps doctors narrow down the possibilities and determine the group of metabolic diseases an infant can be suffering from, including disorders of organic acids, amino acids or fatty acid oxidation.
So doctors can start providing targeted treatments to babies before full results are available after one or two weeks.
In the dried blood spot metabolic test, 0.3mL of blood is collected from an infant and left to dry. Then, after extracting an abnormal metabolite, laboratory staff will move t a reagent into a liquid chromatography - mass spectrometry machine and conduct data processing.
Joannie Hui, the hospital's consultant in pediatrics, said the test can reduce the mortality rate of infants with inborn metabolic diseases.
In one case, an eight-day-old girl had symptoms of the disease and she had an abnormally high levels of ammonia in her blood.
"If the ammonia levels continued to rise it could cause swelling of the brain, which could damage the brain cells responsible for breathing," she said. "The baby could have died."
But the screening enabled doctors to narrow down the possibilities to fatty acid oxidation and to provide targeted treatment while awaiting a confirmation test. The girl is currently in stable condition.
It was later confirmed that the girl suffered from a deficiency that could have led to death within hours.
Chloe Mak Miu, a consultant in pathology, said although the test is not new in Hong Kong the waiting time could take weeks and patients might not receive life-saving treatment.