Is The Foot Prick PKU The Right Choice For You?

December 12, 2020

This is an often routine, and sometimes mandatory test for newborns, in some states! However, most providers don't really give informed consent for this test as they should be doing. It's always good to know stats, benefits and risks to make an informed decision, especially if you are an unassisted birther that is seeking out a provider for the sole purpose of obtaining PKU testing for your new baby!

I was inspired to write this article because I have recently seen a few doula clients deal with providers telling them that their "baby has a huge risk of death if they decline the test," when they questioned the necessity of having their baby's foot pricked. However, I found it odd that when I or the family asked, those same providers failed to provide even the simple information, especially statistics, as stated in the article below. I personally feel that if a provider puts so much stress and fear into a test, they should be able to provide at minimum, this information to the parents so they can make a clear decision.

So first, let's see, what does the newborn screening typically test for? What do those genetic abnormalities mean for your baby? How rare/common ARE they? And what is the typical treatment if discovered?

Biotidinase deficiency

A lack of ability to recycle biotin in the body

Occurrence rate: 1 in 60,000

Treatment: biotin supplementation


A lack of ability to remove ammonia from the body

Occurrence rate: 1 in 57,000

Treatment: low protein diet, arginine supplementation, blood tests to monitor levels and liver transplant in extreme cases

Congenital Hypothyroidism

A low functioning thyroid

Occurrence rate: 1 in 2750

Treatment: iodine supplementation and follow up monitoring for thyroid

Congenital adrenal hyperplasia

A genetic abnormality that prevents the body from producing adequate Cortisol. There are several different variations of this. This can lead to poor digestive capabilities, hormone production and thyroid function, usually later in life, but in more severe cases, it can lead to dehydration in newborns due to failure to absorb and retain hydration. This test has one of the highest false positive rates of all that the Newborn Screening tests for, leading to 200 falsely diagnosed newborns being followed up with for every ONE true positive result.

Occurrence rate: The mild form can be found in about 1 in 1,000 babies, however, the severe form is much more rare, being found in approximately 1:15,000 babies.

Treatment: For mild cases, children are often recommended to be placed on steroids and a cortisol supplementation, especially when ill. For more severe cases, females may require genital reconstruction, and higher doses of hormonal, cortisol and steroid prescriptions, as the child grows, especially.

Cystic Fibrosis

Mutation in the CFTR gene, causes altered properties of secretions as a result of altered chloride transport

Occurrence rate: 1 in 4000

Treatment: physiotherapy & antibiotics

*a sweat test for CF is actually said to be more accurate than the newborn screening*


galactose-1-phosphate uridyl transferase (GALT) deficiency

Occurrence rate: 1 in 50,000

Treatment: galactose-restricted diet


Over abundance of phenylalanine in the body due to a PAH gene mutation, which can lead to poor brain development.

Occurrence rate: 1 in 14,000

Treatment protocol: phenylalanine-restricted diet

Pompe Disease

Caused by a mutation in the GAA gene (acid alpha-glucosidase), this disease is known by the build up of glycogen, a sugar molecule. This build up can lead to organ and muscular damage. Not all types of Pompe disease are infantile.

Occurrence rate: Varies based on where one is in the world, as it appears to be more prevalent in certain gene types, such as African American and Chinese people, so the occurrence rate ranges anywhere from one in 15,000 to as rare as one in 600,000 in infants.

Treatment protocol: Enzyme therapy to reduce glycogen build-up, as well as monitoring via several specialists. Infantile Pompe Disease typically leads to a life expectancy of about 2 years, due to cardiac failure.

Medium chain acyl CoA dehydrogenase (MCAD) deficiency

This disorder prevents the body from appropriately breaking down fats, to convert into energy, which can result in hypoglycemia (low blood sugar).

Occurrence rate: 1 in 10,000-27,000 dependent upon ethnicity.

Treatment: Frequent feeding/eating, supplementing with L-Carnitine, and a high carb diet usually prevents any short or long term issues. If the child goes long periods without eating they could go into hypoglycemic shock or seizures, so frequent meals is the most important part.

Methylmalonic acidemia

A condition in which the body has a hard time breaking down certain types of fats, due to the lack of cobalamins A and B usually, leading to an imbalance in organic acids and toxins in the body. Signs of this may include unusual fatigue, poor muscle tone, fever, trouble breathing, and unexplained bruising.

Occurrence rate: 1 in every 50,000 to 100,000 infants

Treatment: Preventative supplementation of B12 injections, L-Carnitine, and sometimes preventative antibiotics are prescribed. Like MCAD Deficiency, frequent eating is critical for those with Methylmalonic acidemia, as well.

Maple syrup urine disease

Named and characterized by the smell of maple syrup in the urine, this disease means the body is failing to break down three specific amino-acids: leucine, isoleucine and valine. This is a disease that presents very quickly, usually even quicker than test results for the newborn screening can even come back (24-48 hours of life), showing symptoms like poor feeding, weakness, spastic muscles, and lethargy.

Occurrence rate: 1 in 185,000 infants

Treatment: A liver transplant seems to be the only CURE for MSUD, however, symptoms can be managed with a protein restricted diet, and thiamine supplementation.

Mucopolysaccharidosis type 1

This is a hereditary condition in which lysosomes in the body fail to process complex sugars. This condition has a large range of severity, age of onset and outcomes, and it is not typical for this condition to present symptoms in infancy. Early symptoms look like umbilical hernias, disproportional head shape, developmental delays, hearing loss, and cloudy eyes.

Occurrence rate: 1 in 100,000-500,000

Treatment: Enzyme replacement therapy, physical therapy, and stem cell therapy are all options to help alleviate and reduce symptoms, however there is no current cure, and most of kids with severe MPS1 will pass away before adolescence due to heart or respiratory failure.

Sickle cell disease

Most people are familiar with the term Sickle Cell Disease/Anemia as a scary blood disorder, but do not know what it entails. For a child to present with symptoms of Sickle Cell, they must receive the Sickle Cell gene from BOTH parents, otherwise, if they just receive one gene, they will only be a carrier. Basically, in Sickle Cell Disease, instead of healthy, round red blood cells, the body produces red blood cells that are shaped like a sickle tool, in a C-shape, that are sticky and hard. These misshaped cells stick together and do not easily move throughout the body, leading to poor oxygen levels throughout muscles, organs, and important body systems. Most infants start showing symptoms within the first 5 months of life, including paleness, bruising, lethargy, extreme jaundice, pain (primarily in extremities), pneumonia-like breathing, and enlarged spleen. Kids with Sickle Cell are considered immunocompromised, and the primary long-term effects of Sickle Cell disease are concerns revolving organ damage. Life expectancy for those with Sickle Cell is actually pretty great, many living well into their 50s.

Occurrence rate: 1 in 70,000-80,000

Treatment: Hydration is very important to reduce pain in those with Sickle Cell, blood transfusions, preventative antibiotics (the thought process being that infections enhance Sickle Cell symptoms), stem cell transplants, folate supplementation, Hydroxyurea prescription (to reduce number of sickle cells), and pain medication to treat random pain caused by sickle cell clumping. Spleen removal also usually occurs very early in life to prevent splenic pooling of sickle cells, which leads to infection.

Spinal muscle atrophy

There are several different types of SMA and symptoms may range anywhere from as mild as clumsiness to poor chest muscles leading to ventilator requirements, feeding support and wheelchair assistance. SMA is the dysfunction and deficiency of the SMN (survival motor neuron) genes.

Occurrence rate: 1 in 6,000 infants have SOME form of SMA

Treatment: There is no cure for SMA at this time.


An inherited disorder that causes the body to have less hemoglobin, meaning blood cells aren't carrying oxygen normally. This ranges in severity from mild to severe, and there are two different types, alpha and beta, which impact people differently. Most children won't show symptoms until closer to or after two years of age. This can lead to poor organ function, slower growth, wider bones, and those with thalassemia are technically considered immunocompromised.

Occurrence rate: 4.4 in every 10,000 births

Treatment: It depends on the severity! Some will only require taking an over the counter iron supplement or supplementing their diet, while others will need frequent blood transfusion.


This is a metabolic disorder in which the body is unable to process the amino acid, tyrosine. There are three types of Tyrosinemia! The concern with being unable to process tyrosine, is that the build up of it in the organs can lead to liver, kidney, other digestive, and brain problems.

Occurrence rate: 1 in 100,000, except in French-Canadian populations where it is more like 1 in 12,500

Treatment: It will vary based on which type it is and how severe the case is but may include a liver transplant, dietary restrictions, and/or medication to help the body process tyrosine.

X-linked adrenoleukodystropy

This can also be known as Addison Disease or Cerebral Adrenaoleukodystrophy. The ALDP transporter protein in those with this condition is unable to transport very-long chain fatty acids, which in turn leads to peroxisomes failing to be processed, so these fatty acids build up and cause damage to the nervous system and adrenal system. Symptoms will usually present around 4-10 years in boys about 35% of the time, and otherwise will show in adulthood. It primarily impacts males.

Occurrence rate: 1 in 17,000

Treatment: Modified diet of fats, bone marrow transplant, and hormone replacement are all used depending on the severity and needs of the patient!

To Wrap It Up

Whew, that was a lot of info, huh?? Do not be intimidated by it. This guide is purely to briefly breakdown the stats and facts of each of the things that the newborn screening tests for, why, and what the treatment is if your child does have this genetic disorder, so you can make an informed choice on whether or not to have the test performed. Also always keep in mind, that ALL tests come with a false positive rate. If you get a positive on your child, they still may not have it! Ask for a second, third, and more opinions.