Failure to Thrive in Babies and Pompe Disease

What Is Failure to Thrive?

Failure to thrive occurs when a child does not meet standards of length, height or weight. “Poor growth” is a more accurate and less emotive term.

It occurs when a child is undernourished. They either don’t receive enough food, or are unable to process enough calories, or are using calories too quickly.

It is normally identified during the first year of life by comparing a child’s weight, height, and age to national averages of children of the same sex. Growth is best evaluated by plotting serial measurements on a special chart that doctors use, called a centile weight chart. Children who fail to thrive usually fall well below their ideal weight. A child who is tracking downwards on the charts may have poor growth and needs some tests to find out what’s wrong, but not all children who are tracking downwards on the charts have something wrong. 

The most common cause of failure to thrive is not taking in enough calories. 

Other causes include:

• Mental health or social problems at home e.g. Post natal depression

• Inadequate absorption of calories e.g. cows milk protein intolerance

• Excessive use of calories e.g heart failure

• Genetic diseases

Here is a good explanation for parents of signs and symptoms of failure to thrive. 

Pompe Disease and Failure to Thrive

Pompe disease is due to a spelling mistake in the GAA gene in the DNA that parents pass on to their children. The spelling mistake results in complete or near-complete loss of an enzyme called alpha-glucosidase.

Early-onset (or Classic Infantile Pompe disease) begins in the first months of life, with feeding problems, poor weight gain, and muscle floppiness.

Because the enzyme does not work properly, harmful bodily byproducts build up in the cells of the body. More than half of all infants have enlarged tongues and the heart becomes enlarged. Because the heart is enlarged it does not work properly, which causes fluid in the lungs and breathing problems.

Without treatment within a few days of birth, most babies with Pompe disease die from heart failure or lung problems before their first birthday.

Pompe disease is rare, occurring in about 1 in every 138 000 births, so about 3 babies are born with Pompe each year in Australia.

What is my risk for having a child with Pompe disease?

Approximately 1 in 101 people in Australia have the spelling mistake for Pompe disease hidden in their genes, and most people don’t it as there is usually no history of Pompe disease in their family. If parents have genetic testing themselves before they fall pregnant they can know if they have the spelling mistakes that may cause Pompe disease in their children, and can be fully informed about the chance of having an affected child. If a child is at increased risk, parents can have IVF to reduce the chance their child will be affected. Obstetricians recommend that all parents be offered genetic testing that checks for spelling mistakes in their DNA that cause genetic diseases in their child — this is called carrier screening.

Newborn Screening 

Many countries do a blood test when babies are 2 days old to identify treatable medical conditions like Pompe disease early, before problems occur. Eight states in the USA, and Taiwan, screen for Pompe disease because if it is found early treatment is more effective.  

The public health system in Australia does not screen for Pompe disease and 1 or 2 babies die every year in Australia because the condition is identified too late, after irreversible problems have occurred. 

Genepath have a newborn screening test that screens for over 30 treatable genetic conditions not screened in the public system in Australia including Pompe disease. 

Treatment 

The treatment comes in the form of Enzyme Replacement Therapy called Myozyme which is administered by injections. In Australia, this injection is usually done once a fortnight. In most patients, this treatment slows down or halts the progression of Pompe disease.

Pompe disease can be devastating for families. The first sign that a child may have Pompe disease is failure to thrive. The key to allowing families affected by Pompe disease to have the healthiest family life possible is through genetic testing of parents before they have a child, or early diagnosis by newborn screening when the child is born.

For more information about Pompe disease, you can contact the Australian Pompe Association. Here is a video from their website about the tragic late diagnosis of Pompe in one Australian Family.