Who would have guessed that five drops of blood contain enough information to save a baby’s life?
Newborn screening — previously known as a metabolic screen, or PKU test — is performed shortly after birth and can help look for many devastating diseases, explained Melissa Messerly, MD, a pediatrician with Trinity Health.
“We’re testing for minimally symptomatic diseases that are treatable,” Messerly said. Diseases include cystic fibrosis, amino acid disorders, hypothyroidism, and more.
Babies with disorders identified through newborn screening may seem healthy at birth, and you may not be able to tell they have a disorder just by looking at them, explained Joyal Meyer, RN, MSN, director of the North Dakota Newborn Screening Program. But testing early is important because by the time symptoms appear, irreversible damage may have already occurred.
“The illnesses we are screening for are uncommon, but most of them are very serious, often resulting in seizures, intellectual disabilities, or death,” said Michael Holland, MD, a pediatrician with Trinity Health.
The screening looks for about 50 diseases, which, if caught early, can be treatable. “We’re not screening for things we can’t do anything about,” Holland added. “We’re screening for illnesses we can fix.”
The screening is performed 24 to 48 hours after birth and is done by collecting blood from the child’s heel — often referred to as a heel stick. The drops of blood are put on a card with five circles, each smaller than the size of a dime. After the card has dried for three hours, it goes by courier to the State Hygienic Laboratory in Iowa. At the lab, different machines are used to detect different analytes — substances whose chemical constituents are being identified and measured. Depending on gestation period, weight, and time the blood is collected, the machines look for principles.
“Any abnormal screening is followed up by the lab, who notifies the short-term follow-up nurse, based out of Iowa,” Meyer said. “The nurse calls the baby’s primary care physician in North Dakota with follow-up recommendations or for further testing to confirm whether or not the baby has a disorder.”
Time is of the essence for the screening — so much so that if the specimen is sent to the lab in Iowa within 24 hours after collection, the physicians can be notified of a possible time-critical disorder by the time the baby is three or four days old. Parents are notified by the doctor’s office to bring their baby in for further testing right away.
“We want babies identified early so that treatment can begin immediately to avoid any long-term consequences,,” Meyer said. “If babies are not identified early, the disorders can cause brain damage, coma, or even death.”
One disorder screened for is medium-chain acyl-CoA dehydrogenase deficiency (MCAD), an illness that causes blood sugar to get too low if the child doesn’t eat often enough. “Frequent feedings prevent the problem, and IV fluids can be given if the child can’t eat due to an illness,” Holland said. “But if the family and physician are not aware of the illness, the first symptoms would be when the child is having seizures due to low blood sugar levels.”
According to Meyer, it’s more common to have normal results. “The disorders we are screening for are very rare.”
When a child is born at Trinity Hospital, parents get an information form that explains the screening process. A parent may decline to have the test done, but this is usually because of the misconceptions about the testing, the use of the blood sample, or insurance concerns, Holland said.
The testing is safe, and the blood is not used for anything else. The blood specimen is stored securely until the child is 18 years old, and then is destroyed, he added. “If the family has concerns about the retention of the blood specimen, they an request their baby’s specimen be returned to them and destruction would be their responsibility. The information obtained is only shared with the family and the medical care provider.
“The risks for not doing the test are immense,” Holland said. “It would be unfortunate if the child had an easily correctable problem that was not recognized until the child was permanently damaged.”
To learn more about the disorders tested for during a newborn screening, visit the State Hygienic Laboratory’s website.