Panel to Advise Testing Babies for 29 Diseases

But opponents say that for all but about five or six of the conditions, it is not known whether the treatments help or how often a baby will test positive but never show signs of serious disease. There is a danger, they say, of children with mild versions of illnesses being treated needlessly and aggressively for more serious forms and suffering dire health consequences.

And both sides agree that the tests unintentionally pick up about 25 other conditions, in addition to the 29 that the screening is intended to find. These additional conditions show up as abnormalities, but no one knows what they mean. It is not known whether they are associated with a disease or, if so, what the effects will be.

The federal advisory group recommended informing the parents of such results. But that advice, too, is controversial.

"Giving parents the result, saying, 'Here's the mutation; we are not sure what the outcome will be,' is better than not telling," said Sharon Terry, president and chief executive of the Genetic Alliance, an advocacy group for people with genetic disorders. Ms. Terry said it was paternalistic for doctors to presume that it was better for parents not to know.

Dr. R. Rodney Howell, a professor of pediatrics at the Leonard M. Miller School of Medicine at the University of Miami and the chairman of both the committee that wrote the report and the federal advisory group, agreed.

"Do I feel it will be difficult for physicians and caretakers to deal with this?" Dr. Howell said. "The answer is yes. But I just don't think it is proper for us to have information about an abnormality without conveying it."

But Dr. Lainie Friedman Ross, a pediatrician and medical ethicist at the University of Chicago, said: "We don't know if they are medical conditions. We don't know what to do with the information. Reporting test data for which there are no systems in place for follow-up testing and treatment is not rejecting paternalism, but it is patient abandonment."

In any event, Dr. Howell said, noting that states were plunging into testing programs: "It's not really a question of, 'Should we expand newborn screening?' It's happening. It's going like a house on fire."

In most states today, parents are not asked if they want their babies tested, though they have the right to decline it; it is simply done, with the cost, about $70 to $120, built into their hospital bills. Dr. Howell said the idea of the new recommendations was "to try to organize the programs and to try to be consistent from state to state."

"Some states screen for four conditions; others screen for 35," said Dr. Michael S. Watson, the federal project's director and the executive director of the American College of Medical Genetics. "A family can have their first child in one state where 25 conditions are screened and then move to another where only four are screened."

Yet, critics say, the fact that testing is happening does not mean that it should be expanded. The history of newborn screening, they say, is filled with cautionary tales.

"The majority of newborn screening tests have failed," said Dr. Norman Fost, a professor of pediatrics and director of the program in medical ethics at the University of Wisconsin. Over the years, Dr. Fost said, "thousands of normal kids have been killed or gotten brain damage by screening tests and treatments that turned out to be ineffective and very dangerous."

To those who ask what is wrong with simply doing every available screening test, Dr. Fost tells what happened with PKU, the first genetic screening test for newborns. Today every state tests for PKU, or phenylketonuria, and it is widely acknowledged as the perfect example of screening that saves lives and prevents disability. But Dr. Fost says that a few decades ago, the situation was not nearly so rosy.

The disease, affecting one in 14,000 babies, or about 300 each year, involves a missing or defective enzyme that metabolizes the amino acid phenylalanine. Untreated, it leads to mental retardation and neurological damage. But a special diet low in phenylalanine can prevent those consequences.

PKU and its cause were understood by the 1950's, but little could be done. By the time anyone knew there was a problem, the baby was several weeks old and the damage was done.

In 1959, Dr. Robert Guthrie, a microbiologist at the University of Buffalo whose niece had PKU and who was passionate about stamping it out, developed a simple blood test for the condition. Then he began to lobby and soon every state had a law mandating that newborns be tested for PKU.

The testing made two assumptions: that a positive test meant a baby had the disease, and that the special diet was safe and effective.

"Both were stone cold wrong," Dr. Fost said.

Some babies testing positive did not have PKU. Although no one knew it at the time, these babies had a different mutation that was of no clinical significance.

And the special diet could be as dangerous to these normal babies as a regular diet was to babies with PKU.

"If you give a normal kid a diet without enough phenylalanine, not only is there brain damage but every cell in the body is malnourished," Dr. Fost said. "Normal kids became brain-damaged. Many died."

In the mid-1960's, the American Academy of Pediatrics wrote a letter to the secretary of health, education and welfare, Dr. Fost said.

"They said: 'There is a big problem here. We don't know what a true positive test means. We can't distinguish a true positive from a false positive, and we don't know what the right dose of the diet is. Mandatory screening programs should be stopped.' "

But nothing was done, Dr. Fost said, adding, "This train had left the station, and no one wanted to say we had screwed up."

Finally, by the 1970's, the problems were sorted out. Researchers learned to distinguish true PKU from the innocuous condition and how best to prevent the consequences of the disease with a diet. "Now it is an exemplary program," Dr. Fost said of PKU screening.

PKU was not the only screening test that ran into problems.

It happened, for example, with a test for acidic blood in premature babies, whose immature lungs have difficulty excreting carbon dioxide. The gas combines with water in blood to form carbonic acid. Eventually blood can be acidic enough to be lethal. The treatment seemed obvious: neutralize the acid with intravenous bicarbonate of soda. So for more than a decade, from the 1960's until the mid-1970's, every hospital in the country routinely screened premature babies for acidic blood and treated them with bicarbonate of soda.

"It had a religiosity to it," said Dr. Michael Simmons, a professor of pediatrics at the University of North Carolina. "You see blood that was acidic, and you have a drug that can fix it."

But with Dr. Frederick Battaglia, now an emeritus professor at the University of Colorado, Dr. Simmons and his colleagues discovered that babies who got bicarbonate of soda actually did worse and, in particular, had more brain hemorrhages, which can cause devastating brain damage.

Their study, published in 1974, changed medical practice. And Dr. Simmons said it taught him a lasting lesson: "Don't begin therapy until you know it will work."

Dr. Fost said that lesson was all too often forgotten.

"In all these cases of newborn screening gone haywire, there is usually some understandably zealous group of parents of sick kids, patient groups, advocacy groups saying 'Let's get on with it,' " Dr. Fost said. "Some ethicists asked for clinical trials, but these groups said, 'We don't have time to waste.' "

But parents of children with genetic diseases often tell a different sort of story.

Micki Gartzke of Shorewood, Wis., gave birth to a girl, LeA, on Oct. 14, 1996. When LeA was just a few months old, her body became rigid, she would not eat and she cried inconsolably. She was found to have a rare genetic disorder that made her deficient in an enzyme, galactocerebrosidase, needed in the early stages of brain development. After two years of suffering and a quarter of a million dollars in medical bills, LeA was dead.

Early diagnosis, Ms. Gartzke said, could have led to a lifesaving transplant of umbilical cord blood.

The question posed by the new screening recommendations is whether they will lead to the kind of dangers that followed early PKU testing, or whether they will correctly identify babies like LeA who might have been saved.

Medical specialists say it is difficult to know.

Some, like Dr. Nancy S. Green, the medical director of the March of Dimes, say that each of the 29 conditions "has a reasonable intervention."

The treatments make medical sense, Dr. Green said, and experts in the diseases advise using them. "Keep in mind that there was considerable expert input," she said.

The disorders are extremely rare, she and others said, making it unrealistic to demand the most rigorous scientific studies of the tests and their treatments. With just a few dozen babies born with a condition each year, it could take decades to get such data. Medical experts have little choice but to use their informed judgment about the tests and the therapies.

But Dr. Ellen Wright Clayton, a professor of law and pediatrics at Vanderbilt University, said that in assessing treatments, the committee had relied mostly on "the lowest form of evidence": the personal opinions of medical specialists and advocacy groups.

Dr. Jeffrey Botkin, a professor of pediatrics and medical ethics at the University of Utah and chairman of the ethics committee of the American Academy of Pediatrics, asserted that only PKU and perhaps five other conditions among the 29 had treatments that were known to work.

Tests he considers problematic include those that identify disorders like citrullinemia and arginosuccinic aciduria, which lead to an accumulation of ammonia and can result in coma and death; and tyrosinemia, caused by a missing enzyme, which can be lethal unless the child has a liver transplant. Each disorder affects fewer than 100 babies a year.

"The conditions are not well understood, the spectrum of the disease is not well understood, it is uncertain how efficacious the treatments are, and it is uncertain how well people can tolerate the treatments," Dr. Botkin said.

When little is known about the effectiveness of screening and treatments, Dr. Botkin said, that raises concerns about babies who test positive but have a mild form of a disorder. He added that screening tests typically picked up substantial numbers of such babies.

Even if the treatment is not onerous, these people "will go through a lifetime of being labeled with a condition they might never have gotten sick with," Dr. Botkin said. "That may be a price that is acceptable if you are saving lives," he said, "but not if you are not saving lives or if you don't know if you are saving lives."

The next step will be to issue the report, which has been presented by panel members but has not been made public. Then comments will be solicited. But, said Dr. Watson, "the public comments won't change our report," which he said would be published in the journal Pediatrics. The comments, he said, will be used by Michael O. Leavitt, the secretary of health and human services, in deciding what to recommend.

Dr. Watson says uniform newborn screening is a matter of equity if nothing else. A diagnosis can be delayed until it is too late simply because the baby was born in the wrong state.

But equity, once again, depends on who is asked.

"Fairness is only an issue when you talk about benefits," Dr. Fost said.

And the benefits, he added, are largely unknown.