Pilot Study #2

Newborn screening for a set of 19 additional metabolic disorders

Can you tell me more about what is included?
The disorders include a variety of conditions that lead to a chemical imbalance in the body. The disorders can lead to vomiting, problems with salt and water balance, developmental problems, or even coma and death. Some of the conditions have better treatments available at this time than others. The outcome of treatment can range from good to poor and depends partly on how much harm occurred before treatment took place.

Some of the disorders have to do with the baby's problems in changing stored fat to a form (fatty acids) that can be used for energy. The names of these fatty acid disorders start with letters that describe the size of the fatty acids that occur in the chemical imbalance, for example S (short), L or LCH (long), VL (very long), or M (medium). The rate of the short and long types, taken together, is only one per 30,000 newborns and less is known about them than about the type of disorder with medium-size fatty acids, (MCAD). MCAD is now included in routine mandated screening. However, there is some proof that all types of these conditions may benefit from some of the same types of dietary management used for MCAD.

Body proteins are made up of building blocks called amino acids. Some of these amino acids are involved in a variety of the disorders included in this screening. For example, in the disorders called tyrosinemia type I or tyrosinemia type II, there is a buildup of the amino acid tyrosine. This is associated with liver failure (in type I) or problems with the eyes, skin, or general development (in type II). Treatment can range from special diets (in type I or II) to liver transplantation (in type I). Other amino acid disorders, called argininemia, argininosuccinic aciduria, citrullinemia, and "HHH" syndrome, are associated with toxic buildup of ammonia in the blood This could lead to coma or death. Treatment is with a special diet and special medications.

Some of the other disorders are caused by buildup in the body of organic acids which can be toxic. Examples are propionic acidemia, or methylmalonic acidemia, isovaleric acidemia and glutaric acidemias I and type II. Vomiting, with loss of body fluids and salts, can lead to coma and death if untreated. Symptoms may begin as early as a few days after birth or not until months later. Treatment usually consists of a special diet and special medications.

What is the chance that my baby will have one of these 19 disorders?
We really do not know how many Massachusetts babies have these 19 disorders. By doing this test, we estimate that we will detect 4-6 Massachusetts babies each year.

What is the pilot program going to study?
The plan is to use new technology (called tandem mass spectrometry) to look at markers that can tell us which babies have disorders that have not been included in routine newborn screening. The study will find out how often these disorders occur in the Massachusetts population, and whether the technology is useful. No extra blood will be taken from your baby. Two types of natural chemicals, called amino acids and acyl carnitines, will be measured in your baby's blood. If these substances are found in unusual amounts in your baby's blood , the Newborn Screening Program will call your baby's doctor about the result. Your baby's doctor would then contact you, and work with you to arrange for your baby to be seen by a Metabolic Disease specialist. The specialist would perform further tests to find out whether or not your baby actually has one of the disorders.

If my baby is one of the babies who needs to be seen by a Metabolics Disease Specialist, where would I find the specialist?
Your baby's doctor would help you. The New England Newborn Screening Program is working with a network of these specialists. Together they will make sure that the most up-to-date information available will be used to care for babies identified through this pilot study. If your baby's screening result indicates the need for a specialist, the Newborn Screening Program will make sure that your baby's doctor knows about these services.

Why are you asking me for a decision? Doesn't my baby's doctor know?
There is good reason to believe that the program can work (testing is accurate) and that the program is worthwhile (benefits of early intervention outweigh the risks). But before a requirement for this additional newborn screening is recommended, the Massachusetts Newborn Screening Advisory Committee would like the answers to these questions:

• How many Massachusetts babies have these disorders?
• How much will babies benefit if they are identified by the Newborn Screening Program?
• Will the screening test be accurate and identify only those babies who have the disorders, without falsely identifying babies who do not have the disorder?

As a parent, you are being asked whether you want to participate in this "pilot study ", to help find the answers to these questions. We expect that most parents will want to get this test for their baby, but we understand that some parents might have personal reasons for not taking part in the pilot study. Because of this, the choice is being offered to you, rather than to your doctor or healthcare provider.

Additional information on the 19 metabolic disorders included under pilot study #2 is available by clicking here.