Failure to Thrive in Cystic Fibrosis

Your Questions About Failure to Thrive Answered

Tensed father looking at ill son in hospital
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Failure to thrive. Ugly as those words sound, they are often among the first that parents of children with cystic fibrosis (CF) hear from their health care providers to explain their child’s poor weight gain. Many times, they are also the words that ultimately lead to a CF diagnosis.

If your child has been diagnosed with failure to thrive, you are probably confused, scared, and maybe feeling a bit guilty.

You may have even faced stares, glares, and accusations from misinformed friends, family members, and health care providers. You are not alone. Most parents in your shoes have questions, and many parents have been wrongly accused of neglect.

Following are the answers to some of the most common questions parents ask when their child is diagnosed with FTT -- you may find some of yours on this list. As always, be sure to discuss your specific concerns with your child’s health care providers.

What Exactly Is Failure to Thrive?

The short answer is that FTT means poor growth. However, FTT is a bit of a vague term because the specific criteria used to determine what constitutes poor growth vary depending on who you ask. Usually, though, FTT means one or more of the following things:

  • Weight has dropped more than 2 percentage lines on the growth chart
  • Weight-for-age is more than 2 percentage lines below the ideal
  • Weight is below the 3rd or 5th percentile
  • Weight-for-length is less than 80% of ideal weight
  • Height-for-weight is less than the 3rd percentile
  • Weight-for-height is less than the 10th percentile

What Causes FTT?

FTT has three basic causes:

  • Consuming too few calories
  • Not absorbing the calories that are consumed
  • Burning too many calories

In kids with cystic fibrosis, FTT is usually caused by a combination of the latter two options. Because of pancreatic insufficiency, kids with CF do not absorb calories properly. The increased work of breathing also causes them to burn extra calories.

Could I Have Done Anything to Prevent FTT?

No. It’s common for parents to feel guilty about their child’s poor growth but the truth is that, until the diagnosis of cystic fibrosis is known and treated, there is nothing that can be done to prevent it. In kids with CF, FTT does not mean that they are not being fed enough. Kids with CF usually have voracious appetites and consume larger than normal amounts of food. The problem is that, no matter how much food is consumed, it will never be enough until the absorption issue is corrected.

If My Child Is Not Thriving, Does That Mean He is Going to Die?

In kids with CF, the cause of FTT is known and easily treated. Without treatment, pancreatic insufficiency could lead to starvation but with proper treatment, your child can grow and thrive as expected.

How is FTT Treated?

FTT is treated by correcting the problems that caused it. If your child with cystic fibrosis is failing to thrive, he probably has pancreatic insufficiency.

If so, he will take enzyme supplements that will allow his body to absorb nutrients. Once the absorption problem is corrected, you will probably meet with a nutritionist who will help you develop a diet plan that meets your child’s increased caloric needs.

Will I Be Reported For Neglect?

In kids who do not have underlying medical conditions, FTT can be a red flag that raises suspicion of child neglect--especially if there are other signs of neglect such as poor grooming or poor parental bonding. If health care providers suspect that FTT is a result of neglect, they are required by law to report it to local authorities.

I’d like to tell you that children with CF are never suspected as victims of neglect but, unfortunately, it does sometimes happen before the diagnosis of CF is made. I have heard many stories from parents who had to endure accusations of neglect and visit several providers before finally getting the sweat test that led to their child’s diagnosis of CF.

Agency for Healthcare Research and Quality. “Criteria for Determining Disability in Infants and Children: Failure to Thrive”. Summary, Evidence Report/Technology Assessment: Number 72. AHRQ Publication No. 03-E019, March 2003.
Block, R.W. and Krebs, N.F. “Failure to Thrive as a Manifestation of Child Neglect”. 2005. Pediatrics. (116)5: 1234-1237. 2009 January 2.