Non-CF causes of elevated newborn IRT???

D

dlo2977

New member
A friend of mine's daughter's newborn screen (IRT) came back elevated in her now 10 month old. The sweat chloride was normal (don't know the number), so they did not pursue it. They were told at the time she was likely a carrier. They are now planning for future children and wanted to make sure they are not both carriers so they got testes (Mom and dad, not the baby). On the basic blood panel, they both came back as not having a mutation. They are aware that a small percentage of mutations are no on the basic panel. Their baby is 10 months old, 21 lbs, no respiratory symptoms.

What are other causes of a high IRT in newborns??? Do they assume she is not even a carrier????

I can't really answer these questions for her since my CF child was born prior to IRT on the newborn screen, so I don't have experience with the test.
 
D

dlo2977

New member
A friend of mine's daughter's newborn screen (IRT) came back elevated in her now 10 month old. The sweat chloride was normal (don't know the number), so they did not pursue it. They were told at the time she was likely a carrier. They are now planning for future children and wanted to make sure they are not both carriers so they got testes (Mom and dad, not the baby). On the basic blood panel, they both came back as not having a mutation. They are aware that a small percentage of mutations are no on the basic panel. Their baby is 10 months old, 21 lbs, no respiratory symptoms.

What are other causes of a high IRT in newborns??? Do they assume she is not even a carrier????

I can't really answer these questions for her since my CF child was born prior to IRT on the newborn screen, so I don't have experience with the test.
 
D

dlo2977

New member
A friend of mine's daughter's newborn screen (IRT) came back elevated in her now 10 month old. The sweat chloride was normal (don't know the number), so they did not pursue it. They were told at the time she was likely a carrier. They are now planning for future children and wanted to make sure they are not both carriers so they got testes (Mom and dad, not the baby). On the basic blood panel, they both came back as not having a mutation. They are aware that a small percentage of mutations are no on the basic panel. Their baby is 10 months old, 21 lbs, no respiratory symptoms.
<br />
<br />What are other causes of a high IRT in newborns??? Do they assume she is not even a carrier????
<br />
<br />I can't really answer these questions for her since my CF child was born prior to IRT on the newborn screen, so I don't have experience with the test.
 
M

Mommafirst

Guest
Here's a link to a good article. I hope you can read it, I'm not sure if you can pull up the whole article -- I'm on a University campus that subscribes to all those journal article databases, but the article basically says (and is in the title) that even high IRT's in newborns if they are not associated with CF that there is no reason for further inquisition. I believe high IRT levels in adults is an indicator of pancreatic issues, such as pancreatic cancer. But that doesn't apply to newborns.

<a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/</a>


Oh and this comes from another site...

<b>What does the test result mean?</b>


If an IRT level is elevated, an infant may have cystic fibrosis; an infant or adult may have abnormal pancreatic enzyme production, pancreatitis, or pancreatic cancer; or the elevated IRT may be a false positive. Elevated levels need to be followed with further testing. If the IRT level is negative but the infant is symptomatic, other testing for CF, such as sweat chloride and/or CF gene mutation testing, should be considered.

<b>Is there anything else I should know?</b>IRT testing is only useful for diagnosis of CF or pancreatic insufficiency. It will not identify heterozygous carriers of a CF mutation. Their trypsinogen production and function will not be affected. In patients who do have CF, the degree of IRT elevation does not reflect the severity of the disease.
 
M

Mommafirst

Guest
Here's a link to a good article. I hope you can read it, I'm not sure if you can pull up the whole article -- I'm on a University campus that subscribes to all those journal article databases, but the article basically says (and is in the title) that even high IRT's in newborns if they are not associated with CF that there is no reason for further inquisition. I believe high IRT levels in adults is an indicator of pancreatic issues, such as pancreatic cancer. But that doesn't apply to newborns.

<a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/</a>


Oh and this comes from another site...

<b>What does the test result mean?</b>


If an IRT level is elevated, an infant may have cystic fibrosis; an infant or adult may have abnormal pancreatic enzyme production, pancreatitis, or pancreatic cancer; or the elevated IRT may be a false positive. Elevated levels need to be followed with further testing. If the IRT level is negative but the infant is symptomatic, other testing for CF, such as sweat chloride and/or CF gene mutation testing, should be considered.

<b>Is there anything else I should know?</b>IRT testing is only useful for diagnosis of CF or pancreatic insufficiency. It will not identify heterozygous carriers of a CF mutation. Their trypsinogen production and function will not be affected. In patients who do have CF, the degree of IRT elevation does not reflect the severity of the disease.
 
M

Mommafirst

Guest
Here's a link to a good article. I hope you can read it, I'm not sure if you can pull up the whole article -- I'm on a University campus that subscribes to all those journal article databases, but the article basically says (and is in the title) that even high IRT's in newborns if they are not associated with CF that there is no reason for further inquisition. I believe high IRT levels in adults is an indicator of pancreatic issues, such as pancreatic cancer. But that doesn't apply to newborns.
<br />
<br /><a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2065933/</a>
<br />
<br />
<br />Oh and this comes from another site...
<br />
<br /><b>What does the test result mean?</b>
<br />
<br />
<br />If an IRT level is elevated, an infant may have cystic fibrosis; an infant or adult may have abnormal pancreatic enzyme production, pancreatitis, or pancreatic cancer; or the elevated IRT may be a false positive. Elevated levels need to be followed with further testing. If the IRT level is negative but the infant is symptomatic, other testing for CF, such as sweat chloride and/or CF gene mutation testing, should be considered.
<br />
<br /><b>Is there anything else I should know?</b>IRT testing is only useful for diagnosis of CF or pancreatic insufficiency. It will not identify heterozygous carriers of a CF mutation. Their trypsinogen production and function will not be affected. In patients who do have CF, the degree of IRT elevation does not reflect the severity of the disease.
<br />
 
P

petnurse

New member
An IRT level can be high due to the baby being jaundice (like the article said about elevated bilirubin), traumatic delivery, and even oxytocin (pitocin) being given to the mother during labor. It is actually not necessarily a small number of mutations missing from the basic panel. The majority of them are actually missing. However, the ones that are the most likely to be seen are in the basic. It is a very limited number (12??? I think). There are many people on this site who searched and searched for their mutation and diagnosis :-(
 
P

petnurse

New member
An IRT level can be high due to the baby being jaundice (like the article said about elevated bilirubin), traumatic delivery, and even oxytocin (pitocin) being given to the mother during labor. It is actually not necessarily a small number of mutations missing from the basic panel. The majority of them are actually missing. However, the ones that are the most likely to be seen are in the basic. It is a very limited number (12??? I think). There are many people on this site who searched and searched for their mutation and diagnosis :-(
 
P

petnurse

New member
An IRT level can be high due to the baby being jaundice (like the article said about elevated bilirubin), traumatic delivery, and even oxytocin (pitocin) being given to the mother during labor. It is actually not necessarily a small number of mutations missing from the basic panel. The majority of them are actually missing. However, the ones that are the most likely to be seen are in the basic. It is a very limited number (12??? I think). There are many people on this site who searched and searched for their mutation and diagnosis :-(
 
D

dlo2977

New member
This is what it says is included in indiana's newborn screen: "Before babies go home from the nursery, they have a small amount of blood taken from their heel to test for a group of conditions. One of these conditions is CF. Newborn screening for CF includes measuring the level of a protein called immunoreactive trypsin (also called IRT) in a baby's blood. If a baby has a high level of IRT, a DNA test is done. Indiana's newborn screen tests for 46 of the most common CF gene changes. However, there are over 1,400 gene changes that are known to cause CF."

Does that mean her baby had a high IRT so she received the genetic test and has one of the 46 genes????? Is that why they said she is just a carrier since she had a neg sweat test?
 
D

dlo2977

New member
This is what it says is included in indiana's newborn screen: "Before babies go home from the nursery, they have a small amount of blood taken from their heel to test for a group of conditions. One of these conditions is CF. Newborn screening for CF includes measuring the level of a protein called immunoreactive trypsin (also called IRT) in a baby's blood. If a baby has a high level of IRT, a DNA test is done. Indiana's newborn screen tests for 46 of the most common CF gene changes. However, there are over 1,400 gene changes that are known to cause CF."

Does that mean her baby had a high IRT so she received the genetic test and has one of the 46 genes????? Is that why they said she is just a carrier since she had a neg sweat test?
 
D

dlo2977

New member
This is what it says is included in indiana's newborn screen: "Before babies go home from the nursery, they have a small amount of blood taken from their heel to test for a group of conditions. One of these conditions is CF. Newborn screening for CF includes measuring the level of a protein called immunoreactive trypsin (also called IRT) in a baby's blood. If a baby has a high level of IRT, a DNA test is done. Indiana's newborn screen tests for 46 of the most common CF gene changes. However, there are over 1,400 gene changes that are known to cause CF."
<br />
<br />Does that mean her baby had a high IRT so she received the genetic test and has one of the 46 genes????? Is that why they said she is just a carrier since she had a neg sweat test?
<br />
 
M

Mommafirst

Guest
They are probably assuming that she is a carrier base don the fact that the sweat was negative and the IRT levels were elevated. something like 90% of the positives for newborn screen are "just carriers"
 
M

Mommafirst

Guest
They are probably assuming that she is a carrier base don the fact that the sweat was negative and the IRT levels were elevated. something like 90% of the positives for newborn screen are "just carriers"
 
M

Mommafirst

Guest
They are probably assuming that she is a carrier base don the fact that the sweat was negative and the IRT levels were elevated. something like 90% of the positives for newborn screen are "just carriers"
 
H

hmw

New member
The large majority of those with elevated IRT's do not have CF; the IRT is elevated due to the various reasons identified above by others who have posted. If one of the risk factors applied to her baby, combined with the normal sweat test and passing at least one screen I'd think things are likely fine.

I would have her ask what the results of the test were, if they found any mutations. The results they were given don't really clarify carrier status. I would also have her ask for the actual results of the sweat test.

Since the baby is perfectly healthy, in light of the normal sweat test and having 'passed' at least this one screen, it seems that the possibility of CF is much lower. For more peace of mind, they can consider re-doing the sweat test, esp if the first one was on the higher end of normal... babies aren't the most reliable population when it comes to sweat tests. If it is on the higher side of normal they can consider Ambry testing. I realize that is a really conservative approach, but as we all know, cf is a serious disease.
 
H

hmw

New member
The large majority of those with elevated IRT's do not have CF; the IRT is elevated due to the various reasons identified above by others who have posted. If one of the risk factors applied to her baby, combined with the normal sweat test and passing at least one screen I'd think things are likely fine.

I would have her ask what the results of the test were, if they found any mutations. The results they were given don't really clarify carrier status. I would also have her ask for the actual results of the sweat test.

Since the baby is perfectly healthy, in light of the normal sweat test and having 'passed' at least this one screen, it seems that the possibility of CF is much lower. For more peace of mind, they can consider re-doing the sweat test, esp if the first one was on the higher end of normal... babies aren't the most reliable population when it comes to sweat tests. If it is on the higher side of normal they can consider Ambry testing. I realize that is a really conservative approach, but as we all know, cf is a serious disease.
 
H

hmw

New member
The large majority of those with elevated IRT's do not have CF; the IRT is elevated due to the various reasons identified above by others who have posted. If one of the risk factors applied to her baby, combined with the normal sweat test and passing at least one screen I'd think things are likely fine.
<br />
<br />I would have her ask what the results of the test were, if they found any mutations. The results they were given don't really clarify carrier status. I would also have her ask for the actual results of the sweat test.
<br />
<br />Since the baby is perfectly healthy, in light of the normal sweat test and having 'passed' at least this one screen, it seems that the possibility of CF is much lower. For more peace of mind, they can consider re-doing the sweat test, esp if the first one was on the higher end of normal... babies aren't the most reliable population when it comes to sweat tests. If it is on the higher side of normal they can consider Ambry testing. I realize that is a really conservative approach, but as we all know, cf is a serious disease.
 
D

dlo2977

New member
It looks like if the IRT is high in Indiana, they test for 46 common mutations. Mom and Dad were only tested for 30 mutations so it looks like she had a miscommunication between doctors and they didn't pick up which parents has the mutation. I think she is less worried about her baby having CF and more was trying to make sure she and her husband were not both carriers for future children (and to tell siblings etc which side the mutation was on....)
 
D

dlo2977

New member
It looks like if the IRT is high in Indiana, they test for 46 common mutations. Mom and Dad were only tested for 30 mutations so it looks like she had a miscommunication between doctors and they didn't pick up which parents has the mutation. I think she is less worried about her baby having CF and more was trying to make sure she and her husband were not both carriers for future children (and to tell siblings etc which side the mutation was on....)
 
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