LCHAD deficiency

Detecting disorders

Testing newborns helps mitigate serious ailments

By KAWANZA L. GRIFFIN

of the Journal Sentinel staff

Monday, May 21, 2001

With just a few tiny drops of blood from the heel of a newborn, doctors can alert parents of inherited problems that may cause blindness, mental retardation or possibly death.

The technology to identify such potential health risks began in the 1960s and has been rapidly advancing over the last decade, allowing the detection of at least 30 rare metabolic disorders and helping to improve the quality of life for many children.

But not all newborn screening programs are the same -- and the state where your child is born determines what testing will be done.

Wisconsin law requires that all babies born in hospitals be screened for 21 inherited disorders before they leave and that babies born at home be screened within a week. The number is one of the highest requirements in the nation, but just across the border in Minnesota, infants receive screening for only five disorders. They're screened for six if they're born in Illinois.

Prior to June 1999, Wisconsin screened for just seven disorders. But in that month, the newborn screening panel increased to 21 when testing was added for seven fatty acid disorders that don't allow babies to properly burn stored fat and seven organic acidemia disorders that affect how the baby digests protein.

One family's story

But for Sarah Carroll, who died in 1992 after a series of illnesses at only six months of age, the testing came too late.

It was not until Jenny Carroll became pregnant with Jane in 1993 - - again experiencing severe nausea and liver problems -- that she and her husband, John, would understand what happened to Sarah.

"We had no answers from the autopsy report, so I was very concerned about (Jane's) health," Jenny said. "It's only a positive thing to know a diagnosis because if you don't, how can you treat it."

Jane, like Sarah, was born prematurely at about 27 weeks and was extremely small. Because of Jenny's persistence that the two pregnancies were similar despite her different blood work results, doctors began to look more closely at the case.

At four months, Jane was diagnosed with long chain 3-hydroxyacyl CoA dehydrogenase, or LCHAD, a fatty acid oxidation disorder, after being placed in a national study. She was immediately placed on a special diet that restricted her fat-intake. If the disorder had not been caught, Jane may have experienced liver failure, fallen into a coma or possibly died.

"I've questioned myself: Should I have known?" Jenny said, reflecting back on losing Sarah, "but I was in the doctor's office 12 hours before she died, and they told me she would be all right. Screening is just a very necessary thing to do (because) every day that goes by is another day that a child's life can be lost."

Jane is now 7 1/2, and leading an active and healthy life. She likes playing outside, eating spaghetti and pretzels, and reading. She has to eat regularly and is sometimes fed through the tube in her stomach, but has no other indications that she has an internal deficiency.

Why to screen

"Screening helps to avoid having the pediatrician figure out what's going on with this kid when he shows up in the office 3 days later ill -- because we already know what's going on," said William Rhead, medical director of genetics at Children's Hospital of Wisconsin and a professor of pediatrics at the Medical College of Wisconsin. "And if there are still questions, we've already ruled out 21 things that it could be."

According to the Centers for Disease Control and Prevention, it is estimated that approximately 4 million infants are born each year and that 3,000 -- or .075% -- will be born with a disorder that could be treated if detected early.

In a recent report, the March of Dimes recommended that every child be tested for at least eight disorders: phenylketonuria, hypothyroidism, galactosemia, sickle-cell disease, congenital adrenal hyperplasia, biotinidase, homocystinuria and maple syrup urine disease.

All states have mandatory newborn screening for phenylketonuria, or PKU, a disorder in which the body can't break down the amino acid phenylalanine, and for hypothyroidism, a thyroid hormone deficiency disorder. Most also routinely test for galactosemia, a rare inherited disorder in which the body can't metabolize sugar. More than forty also routinely test for sickle-cell disease, an incurable blood disorder that occurs primarily in blacks.

But screening is less consistent for biotinidase deficiency and congenital adrenal hyperplasia, which can cause abnormal growth and development if untreated; maple syrup urine disease, which can cause irreversible mental retardation; and homocystinuria, which leads to mental retardation, eye problems, skeletal abnormalities and stroke.

Wisconsin is currently evaluating screening for amino acidopathies, which include homocystinuria and maple syrup urine disease, and hopes to have those added to the panel by the end of the year.

"For many of these disorders, the individuals look externally normal," Rhead said. "Routine, regular blood tests wouldn't pick up the disease, so we have to do specialized testing to find it."

Last year, the American Academy of Pediatrics released recommendations encouraging all states to improve their newborn screening programs by taking advantage of the latest screening technology and to structure their programs so that all states required screening for the same disorders to achieve uniformity.

But although many experts may concede that current screening practices are uneven because each state creates its own screening panel, they realize that standardized screening is not quite as simple as it sounds.

Funding a factor

"Cost is an issue," said Gary L. Hoffman, supervisor of the Wisconsin Newborn Screening Laboratory at the State Laboratory of Hygiene in Madison. "Some states can't really put a finger on exactly what the outcome would be if a baby wasn't detected.

"But if you look at what the medical community is spending to diagnose and treat and then compare what the cost is to identify through screening, you realize that it usually costs more just to diagnose."

Hoffman said that it cost the state about $300,000 to buy a tandem mass spectrometer -- the machine that increases the number of disorders that can be tested and allows quick and accurate screening of numerous blood samples -- but said that an estimated $500,000 will be saved annually by the medical community, insurance and state programs.

In 2000, there were 67,769 babies screened in Wisconsin, and 79 were confirmed to have one of the metabolic diseases included in the state screening panel. Since the 14 additional tests were added in 1999, 16 babies have been determined to have either a fatty acid oxidation or organic acidemia disorder as of December.

Although the "whole idea behind newborn screening is prevention . . there are pluses and minuses," said Jon A. Wolff, professor of pediatrics and medical genetics at the Waisman Center at the University of Wisconsin Medical School.

"Some of the conditions are pretty common, and we can prevent kids from dying or having mental retardation," he said. "But we have the potential to do harm with false positives because in that time of retesting we're making new parents wait for answers, and that is very traumatic."

Each series of screenings costs $59.50, with a little more than half of that money supporting laboratory testing activities and the rest going toward confirmatory testing, counseling for affected children and their families and treatments not covered by third- party payers, such as special dietary formulas or vitamin supplements.

Private tests available

If parents want to have their babies tested for the amino acidopathies that are not a part of the Wisconsin screening panel, they can contact a private laboratory to have this testing done for an additional fee.

Two such laboratories are the Institute of Metabolic Disease at Baylor Medical Center (1-800-4-BAYLOR) in Dallas, and Neo Gen Screening (1-800-892-1288) in Bridgeville, Pa.

In October 2000, President Clinton signed the "Children's Health Act of 2000," a bill containing a series of provisions to protect and improve the health of mothers, infants and children, that included authorization for a newborn screening initiative -- an important step in giving states the resources they need to improve and expand newborn screening.

Although expanded screening programs are already in place in the District of Columbia, New England states, North Carolina and Wisconsin, other states such as Indiana and Georgia are already catching up by initiating plans to improve their own newborn screening programs.

And knowing that makes Jenny feel better that fewer parents will have to experience the tragedy that her family did.

"It's just craziness not to do these tests," she said. "No one should have to go through what we did. You could have a normal looking child one day, and they might catch a cold and die the next."

MEDICINE

NEWBORN SCREENING FOR INHERITED DISORDERS

Recent technology makes it possible for physicians to more accurately diagnose disease in infants. With the aid of a screening device known as a tandem mass spectrometer, clinicians at the Wisconsin Newborn Screening Laboratory can now test newborn babies for 21 different rare and often life-threatening conditions. Here's a look at the disorders the state now screens infants for, symptoms, how often the diseases appear in the Wisconsin population and treatments.

CONDITION

Biotinidase Ddeficiency

SYMPTOMS

Can cause frequent infections, uncoordinated movement, hearing loss, seizures and mental retardation. Can lead to coma and death.

PREVALENCE IN WISCONSIN

1 in 90,000

TREATMENT

Daily biotin supplement

CONDITION

Congenital Adrenal hyperplasia (CAH)

SYMPTOMS

Abnormal genital development. Can lead to death within the first two weeks of life due to loss of salt from the kidneys.

PREVALENCE IN WISCONSIN

1 in 9,500

TREATMENT

Steroid therpy

CONDITION

Congenital Hypothyroidism

SYMPTOMS

Slow growth and bone development. Can cause mental retardation.

PREVALENCE IN WISCONSIN

1 in 3,800

TREATMENT

Oral doses of thyroid hormone

CONDITION

Cyctic Fibrosis

SYMPTOMS

Respiratory disease, digestion, poor growth, can cause death.

PREVALENCE IN WISCONSIN

1 in 4,500

TREATMENT

Postural drainage, antibiotics, nutrition

CONDITION

Fatty Acid Oxidation Disorders (7 types)

SYMPTOMS

Weak muscle tone, lethargy, vomiting. Can cause coma, encephalypathy, liver failure, and death.

PREVALENCE IN WISCONSIN

N/A

TREATMENT

Lowfat diet, carnitine supplement

CONDITION

Galactosemia

SYMPTOMS

Vomiting, liver enlargement, jaundice, failure to gain weight, diarrhea. Can lead to blindness, mental retardation, infection and death.

PREVALENCE IN WISCONSIN

1 in 60,000

TREATMENT

Eliminate dietary lactose, breast milk and formula

CONDITION

Hemoglobinopathies (Hemoglobin diseases)

SYMPTOMS

Pain, vital organ damage, death in childhood. Prone to pneumonia and meningitis.

PREVALENCE IN WISCONSIN

1 in 2,500 1 in 400 (Sickle Cell Disease in African-Americans)

TREATMENT

Prophylactic penicillin until age five

CONDITION

Organic Acidemia Disorders (7 types)

SYMPTOMS

Vomiting, dehydration. Can lead to coma, failure to thrive, delay in development and seizures.

PREVALENCE IN WISCONSIN

1 in 30,000 to 1 in 50,000

TREATMENT

Low protein diet, carnitine or vitamin supplements, avoid fasting

CONDITION

Phenylketonuria (PKU)

SYMPTOMS

Can cause severe mental retardation.

PREVALENCE IN WISCONSIN

1 in 20,000

TREATMENT

A low phenylalanine diet started as soon as possible and continued through adolescence.*

*Low phenylalanine infant formulas are available free of charge through the state's three metabolic clinics.

Source: Wisconsin State Laboratory of Hygiene

Copyright 2001
Provided by ProQuest Information and Learning Company. All rights Reserved.