Fifty years ago, a revolution began in neonatal care that has preserved the physical and mental health, and often the lives, of thousands of babies: screening of newborns for inherited and congenital disorders.
On Oct. 15, 1963, the first law requiring that all newborns be screened for phenylketonuria, or PKU, took effect in Massachusetts. PKU, an inherited metabolic disorder, afflicts one in 20,000 of the four million babies born each year in the United States. Children with PKU are missing an enzyme that converts the amino acid phenylalanine to tyrosine, and unless they remain on a special protein-restricted diet, the resulting buildup of phenylketone damages the brain and causes mental retardation and physical disabilities.
Today every state tests babies at birth for PKU — and not just that. There are now more than 50 disorders that can be picked up through screening, 31 of which comprise the "core conditions" of the government's Recommended Uniform Screening Panel. Other conditions are likely to be added to the panel in the future. All but two of them — hearing loss and critical congenital heart disease — can be detected by automated analysis of a few drops of dried blood from a heel stick done within a few days of birth.
Giana Swift, a fifth grader in Sherman Oaks, Calif., was one of more than 12,500 babies who benefit from newborn screening each year. The story of her birth in October 2002 was recounted in The Times. Through a pilot screening program, Giana was found to have an inherited metabolic disorder called 3-MCC (3-methylcrotonyl-CoA carboxylase deficiency). It afflicts about 100 babies a year, rendering them unable to process the amino acid leucine. As with PKU, toxic byproducts of the unprocessed amino acid build up in the blood and damage the brain.
Because she was tested at birth, Giana thrived, first on a special leucine-free baby formula, then on a diet nearly free of protein. Her grateful father, David Swift, 44, recently described Giana as "very bright, precocious, happy and a top athlete."
"That test and the nurse who talked me into having it done saved my daughter's life," he told me.
Some protein is now being gradually introduced into Giana's diet to see how well her body handles it. All concerned are on alert for symptoms related to 3-MCC: lethargy, weakness, dizziness, dehydration and vomiting. Mr. Swift and Giana, who turns 11 on Saturday, are also "giving back by helping other children with worse problems through the March of Dimes and the Make-A-Wish Foundation," he said.
In the decades before Giana was born, the number and quality of newborn screening tests varied widely from state to state. In 2008, the Newborn Screening Saves Lives Act was adopted, establishing national screening guidelines and financial help for every state to create a comprehensive screening program. The law, which also provides professional education, parental support and a check on laboratory reliability, is up for renewal.
Conditions that can be detected through newborn screening include hormonal disorders like thyroid and adrenal abnormalities, blood disorders like sickle-cell anemia, severe immunodeficiencies, and dozens of enzyme disorders that result in a wide range of serious and sometimes fatal conditions.
Each of these disorders is relatively rare, but the effect of widespread screening has proved to be economical as well as lifesaving, sparing countless children years of costly medical and educational services and institutional care.
The short life of Kaylin Peters is a testament to the need for these programs. Kaylin was born last year in Syracuse, N.Y., with an initially undetected critical congenital heart disorder. The defect afflicts 18 in every 10,000 newborns.
Although Kaylin seemed normal at birth, a major heart defect was found weeks later when she failed to thrive, bled abnormally and began to turn blue. Despite surgery to repair the large hole in her heart, Kaylin died in December at age 9 months. Her mother, Krystal Peters, 31, is now working hard to make sure children with life-threatening heart defects are diagnosed before it's too late.
Ms. Peters wants every newborn to have a pulse oximetry test that can reveal a shortage of oxygen in the blood resulting from a heart defect. As of last January, the test was required and fully implemented in only six states, including New York.
And because an oxygen deficiency may not be apparent within a few days of birth, Ms. Peters also wants every parent "to go home from the hospital with a list of symptoms" of critical congenital heart disorder, which include excessive sleepiness, sweating while nursing, and skin with a bluish or purplish color.
Pulse oximetry checks the baby's pulse and blood oxygen level through a sensor attached to a finger or foot. Ideally, babies with normal results in the hospital are tested again at the first visit to a doctor.
"More than half of affected children require lifesaving surgery within the first months of life," Ms. Peters said in an interview. "I don't want what happened to Kaylin to happen to any other baby."
Each state decides which conditions to test for; most now screen for at least 20 disorders. But with more babies now born outside hospitals, it often becomes the parents' responsibility to get newborns screened before they are a week old.
An abnormal result on a screening test does not necessarily mean the baby has a problem; additional diagnostic testing is required. If a diagnosis is confirmed, parents are told how best to care for the baby to maximize the chances of normal development. If a newborn is found to have hearing loss, for example, a treatable cause may be responsible. If the condition cannot be corrected, speech therapy, sign language or cochlear implants may minimize its severity.
Dr. Edward R. B. McCabe, a pediatric geneticist and medical director for the March of Dimes, whose career has spanned the history of newborn screening, envisions an exciting future for early detection and treatment of inherited and congenital disorders. In an interview, he said the National Institutes of Health has awarded several research grants for DNA sequencing of newborn blood, which could facilitate the earliest possible diagnosis of health-threatening problems.
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