Newborn screening in Minnesota found effective but with challenges
Most late-onset Pompe patients lost to follow-up were ethnic minorities
A newborn screening program for Pompe disease in Minnesota was found effective for getting babies with infantile-onset disease started on early treatment, but challenges remain for those with late-onset disease (LOPD).
“The management of LOPD cases including the establishment of standardized follow up guidelines … and a better understanding of the benefits of early detection emerged as the most complicated part of [Pompe disease] screening,” researchers wrote.
That’s according to a study, “Disparities in late and lost: Pediatricians’ role in following Pompe disease identified by newborn screening,” published in Molecular Genetics and Metabolism.
Newborn screening for genetic diseases has become increasingly common
Newborn screening programs for Pompe disease test all babies for the disease within the first few days of life. Babies that test positive can then be referred for additional testing to confirm a diagnosis. As medical knowledge has continued to advance and new treatments become available, newborn screening for Pompe and other genetic diseases has become increasingly commonplace.
The U.S. state of Minnesota implemented a newborn screening program for Pompe disease in 2017. In the study, researchers reported on outcomes from the first four years of the program.
“The objective of this project was to evaluate the screening performance and diagnostic outcomes of children identified with [Pompe disease] through newborn screening in the state of Minnesota over a 4-year period,” the team wrote.
Over the four years studied, more than 250,000 babies born in Minnesota were screened for Pompe disease. Among them, 21 had an abnormal result prompting additional testing, and 17 of these babies were ultimately diagnosed with Pompe. That works out to a prevalence of about one in every 15,000 newborns.
The rate of LOPD identified by the program (one in about every 17,000 newborns) is higher than would be expected based on previous estimates, but the researchers noted that these earlier estimations, done before widespread screening efforts, likely underestimated the frequency of this less severe type.
Another two children, who were older siblings of these babies, were also diagnosed with Pompe disease after positive results in the babies prompted their testing.
Among the four newborns who had an abnormal screening result but weren’t diagnosed with Pompe, two were determined to be disease carriers — meaning they won’t develop the disease, but carry one mutated gene that they could pass to their biological children. One of them had a pseudodeficiency (a mutation known to cause abnormalities on lab tests, but not to cause disease), and the other was determined to be a false-positive.
A majority of those who were lost to follow-up belonged to minority ethnic groups.
2 babies were diagnosed with infantile-onset Pompe, 15 with late-onset disease
Two of the 17 children with Pompe were diagnosed with infantile-onset disease, which is characterized by symptoms that appear in the first year of life, while the other 15 were diagnosed with late-onset disease, in which symptoms can appear anytime after the first year.
No cases of infantile-onset disease were reported in the state apart from the two babies diagnosed via newborn screening. The researchers noted that Minnesota’s program is designed to identify this more severe form of Pompe disease, and both of the babies diagnosed were able to start on treatment within two weeks of birth.
“We continue to closely monitor these patients for any development delay or the presence of any symptoms,” the scientists wrote.
Ten of the babies diagnosed through the newborn screening program, including both with infantile-onset disease, were Caucasian. Among the remaining seven babies, all of whom had late-onset disease, five were African, one was African American, and one was of Caucasian and Native American ancestry.
The researchers noted that infantile-onset disease has been previously reported to be more common among people of African descent, but there’s less data on the ethnic distribution for LOPD.
“Although this information for LOPD is limited in the literature, we found that more than a third of newborns with LOPD are of African American, North African, or East African descent,” the team wrote.
It’s generally recommended that babies suspected of having LOPD through newborn screening be regularly monitored for signs of the disease so that treatment can be started as soon as it’s needed.
6 children with late-onset Pompe were lost to follow-up
Among the 15 babies with LOPD, nine are still being monitored, but the other six have been lost to follow-up. Most of the babies lost to follow-up were African or African American.
“A majority of those who were lost to follow-up belonged to minority ethnic groups,” the researchers wrote, adding that this finding “warrants further investigation to clarify barriers [to receiving follow-up] in this population and solutions to address them.”
Factors such as medical costs and confusing insurance policies likely played a role in the number of patients lost to follow-up, wrote the researchers, who recommended that insurance plans “should allow unfettered access to both (a) appropriate specialists and (b) appropriate FDA-approved treatments.”
The team also highlighted the importance of specialists partnering with primary care doctors, who may be better situated to perform routine follow-up.
To facilitate better care for these children, the three major specialty centers in Minnesota have teamed up with the state’s department of health to form the Minnesota Pompe Disease Consortium.
“The Consortium will use their collective data to help identify areas for potential improvement to both screening and follow-up and will seek opportunities to collaborate with additional stakeholders, like primary care providers, to expand our impact on this patient population,” the team wrote.
About the Author
