Neonatal Alloimmune thrombocytopenia (NAIT)

[akm0036]

What is Neonatal Alloimmune thrombocytopenia (NAIT)? What is the term for what the mother has that causes NAIT? How do I know if my body will "attack" the baby's platelets? This is my first pregnancy. Should I push for testing? Is there any symptoms to let me know if I have what causes this?

I am 24 weeks, planning on a c-section at 37 weeks.

[akm0036]

Thank you for all of your replies. I don't have any sisters, only a brother who has a healthy one year old. I have 2 female cousins on my mom's side who had healthy children. My mom had very easy pregnancies. I am on a message board for pregnancy loss due to early dilation of the cervix and one of the girls there had this condition. I couldnt believe that this would actually happen. How devastating. I was curious if there were maternal symptoms to detect this, which my MFM told me no. Very scary. i am just hoping it all works out. Thank you guys for the responses, it means a lot to me. I am still worried but looks like short of getting tested, it is a wait and see (I do get BPP ever week so maybe that can help???)

[Patchoules]

I'd just like to support Kent's statement. I am the mother of 2 NAIT babies and believe that my second son is a true testament to the fact that the treatment (IVIG) IS a positive therapy for NAIT. We did not realize that our first son had NAIT and were fortunate for the quick action of his NICU doctors in determining the cause of his low platelet count and responding with IVIG and transfusions.

This is clearly a condition that, while rare, needs to be highlighted as a serious but treatable pregnancy risk.

For families seeking more information and support from others with NAIT, please visit the Yahoo Group for NAIT and/or the Facebook Cause.

Be well,
Carrie

[KentW]

Hi,

I am the parent of three NAIT children and very well versed in much of the NAIT research.  While I agree NAIT is not very common, it is more common that once thought and some research puts it at about 1 in 800 pregnancies and others as high as 1 in 2000.  Does it make sense to screen for trisomy 18, which occurs in about 1 in 3000 live births, or trisomy 13 at 1 in 10,000 live births, and not NAIT?  Routine NAIT testing is not common in the US (like it is in Norway), but I know of some parents who request when siblings have experience NAIT, and their doctors order it and insurance covered it.  While I agree with Dr. Brown that there may be other things to be concerned about, I know NAIT parents who felt that way until they lost or almost lost their babies to NAIT.

If you have a sister who experienced NAIT, you have over a 25% chance of sharing her homozygous platelet antigen type, so the risk of NAIT is much higher than the general population, assuming she carries one of the more rare platelet alleles.  If this is the case, I would think Dr. Brown or another MFM would want you tested.  Having over a 25% chance of having a disease that has a 10% to 20% chance of an intracraneal bleed is not trivial, and treatments for NAIT can be nearly 100% efffective if started early enough in the pregnancy.  If you have just heard about NAIT, then it depends if the low risk is worth checking out to you.

If you want to have your and your husband's platelets genotyped for incompatibility or your blood screened for anti-platelet alloantibodies during pregnancy, the testing is avaialble at the Blood Center of Wisconsin or the American Red Cross Platelet Serology lab.  Links to both of those are availble on the links page of www.naitparent.com.

Kind Regards,
-Kent

[tessack]

A related discussion, NAIT baby & subsequent pregnancies was started.

[snekane]

A related discussion, Clarification for Neonatal Alloimmune Thrombocytopenia was started.

[Elaine Brown, MD]

Hi!
NAIT is very uncommon.  If you have no risk factors, such as ITP or TTP yourself, it is very unlikely that this will be an issue for you.
There really isn't a good way to test for this condition, and there are not any very good therapies for it.  So, even if you did have the condition, there is not too much that can be done, except for the possibility of IVG therapy, and a C section for delivery. It is NOT high on the list of things I would be concerned about in a healthy mom!

I hope your doctor intends to check for fetal lung maturity before a 37 week section!
Good luck!
Dr B