Value of newborn tests debated - 7/24/2002

Doctors differ on what genetic-disorder tests should be conducted. Some say it's no use to find disorders that can't be cured. Others say it aids research.

By CYNTHIA RAMNARACE, Evening News staff writer

Within hours of a baby's birth, a nurse comes with a needle and a screening card with the purpose of gathering a few drops of blood.

For most parents, the test is never thought of after that moment. The card is sent to the state laboratory, where the blood is examined for hints of lurking genetic disorders. Most of these disorders occur when both parents are unknowing carriers of the gene that causes the disease. These are rare. Congenital hypothyroidism, one of the more common ones, occurs in one in 4,500 births. Maple syrup urine disease occurs in one in 120,000 births.

They are rare, but they are dangerous, resulting in mental retardation and death if left untreated. So if a baby has one of these disorders, it's best to know before symptoms appear.

Because there's no national standard for which diseases should be tested for, the battery a baby receives depends on where he is born. A baby born in Michigan will be tested for seven disorders. In Ohio, a baby can be tested for up to 28 disorders.

The discrepancy has to do mostly with technology, but also with philosophy.

In January, 2001, the Ohio Department of Health went online with its new mass spectrometer, a high-tech piece of equipment necessary for detecting medium chain Acyl-Coa dehydrogenase deficiency (MCAD). MCAD is an enzyme deficiency that stops the body from converting fat to energy. It is one of nine disorders that the March of Dimes recommends infants be screened for.

The spectrometer also can detect other diseases at minimal extra cost, explained Dr. Bill Becker, medical director for the Ohio Department of Health Laboratory. For that reason, Ohio earlier this month added 16 disorders to its infant screening panel that parents can opt to have their child screened for.

Michigan does not have this device, so it can't screen for MCAD or the extra 16 disorders that affect the body's ability to use fat for fuel and break down proteins. David Johnson, deputy director of the Michigan Department of Community Health, said that his department's newborn screening subcommittee is studying whether to add screening for MCAD and homocystinuria, which are both recommended by the March of Dimes.

Regardless of availability of screening technology, there is a debate as to whether it's ethical to screen for disorders for which there's no proven treatment.

The March of Dimes, which works to prevent birth defects and reduce infant mortality, recommends that states test for nine disorders: phenylketonuria, congenital hypothyroidism, congenital adrenal hyperplasia, biotinidase deficiency, maple syrup urine disease, galactosemia, homocystinuria, sickle cell disease and MCAD.

Neither Ohio nor Michigan tests for all nine disorders recommended by the March of Dimes. Michigan does not test for homocystinuria or MCAD. Ohio does not test for congenital adrenal hyperplasia and biotinidase deficiency.

The March of Dimes selected these diseases because each has an effective and accepted treatment that must be started immediately after birth and the test technology is accurate and reliable, said Bill Axtell, director of communications for the Michigan chapter.

"The March of Dimes monitors the development of new screening technologies and will add to the core list as we think it becomes appropriate," he added.

Dr. Johnson agrees with the March of Dimes rationale.

"One could argue that in some respects, to undertake those tests because you can could be irresponsible and you may wind up doing more harm than good," Dr. Johnson said. "If you're providing information about a condition that is ill-defined and there's no treatment, but you spend the money in doing that, how are we helping that family and child and at what cost?"

The thinking in Ohio is a little different.

"I understand (the March of Dimes) argument," said Dr. Becker. "But right now we are still learning about many of these disorders. Medicine needs to continue to learn more about them before we can say there's no way we can treat them."

Dr. Becker added that the perception that these diseases are rare might be inaccurate, because without testing the true incidence level cannot be known. Realizing the true scope of the problem can help doctors and researchers find the best way to treat them.

And while Dr. Johnson believes it "borders on the obscene" to test for diseases that can't be treated, Dr. Becker says that if you have the technology and don't do it, then that's irresponsible.

For Monroe County parents, the decision on how many disorders their infant will be screened for is up to them. They can choose to give birth in Ohio or Michigan. In Michigan, babies are tested automatically for seven disorders.

In Ohio, the mandatory panel includes 16 disorders. Parents must opt voluntarily for the extra 16 screenings, which require no more blood from the baby and costs the same as the standard panel.

In reviewing those blood samples, there are few positive results. Only one in 3,000 or 4,000 panels will have a positive result, said Dr. Becker.

Infant screening has changed the lives of many children, however.

"There are children you can find in the pre-clinical phase and save from mental illness, retardation and death," said Dr. Johnson. "Newborn screening has been a wonderful program. Had we access to all of these people found by newborn screening, you would hear wonderful, heartwarming testimonials."