PKU Fail

[fyrebloom]

So my DS's PKU came back elevated. I don't know HOW elevated but we just redid it and should know next week if he has it or not. I've been researching of course and now am freaked out (he's very pale and looks like he may have blue eyes... a first as my other kids have dark brown eyes). I know the test has a 90% false positive rate, but i'm terrified of "winning" the genetic lottery so to speak. Luckily my kid's Dr is awesome and just said we're disregarding this one and will test again. No mention of weaning thank goodness. I'll keep you all updated.

[beatgenxer]

Sending positive thoughts to you and malcolm!

[firewoman]

I wouldn't worry just yet, but I'm thinking of you and sending you lots of and ! When will you get the new results back? What do blue eyes and fair skin have to do with PKU? All of my kids are blue eyed and fair and are fine.

[boobs4milk]

hugs lucia. we had some values above normal on the metabolic screens. i was told that false positives are likely if your baby was preemie or if the test was done when baby was less than 48 hrs old. even after 48 hrs, some of the tests still give off false positives. hoping for good news for you!

[Nature]

I was told it was under 24 hours old that the rate of false positives occurred the highest. (its why we didn't go home right away, I didn't want to return to get the PKU done the next day)

Hoping the next test comes out better!

[Serenyd]

Keep us updated! Hope it's nothing and you get your results back quickly.

[StephM76]

I hope the next test comesw back better! There are lots of false positives so try not to stress

[fyrebloom]

Phenalalamine (sp) is broken down by the body to make tyrosine which is in turn used to make melanin. If you can't make melanin because you don't have alot of tyrosine then you have light hair, skin and eyes. My DS is also blond but with brown eyes. It's just something they find in PKU kids... most have blond hair and blue eyes.

The test was done 30 hours after birth and before my milk was completely in, thus it probably is just a false pos. It's just stressful.

[Serenyd]

Originally Posted by fyrebloom

Phenalalamine (sp) is broken down by the body to make tyrosine which is in turn used to make melanin. If you can't make melanin because you don't have alot of tyrosine then you have light hair, skin and eyes. My DS is also blond but with brown eyes. It's just something they find in PKU kids... most have blond hair and blue eyes.

The test was done 30 hours after birth and before my milk was completely in, thus it probably is just a false pos. It's just stressful.

Why would they do it so early knowing it could cause a false +? That seems kind of irresponsible.

[Pandme]

Sending you loads of good vibes.

[fyrebloom]

Because it's cheap and will catch all the ones who DO have the disease. In general you have your choice between highly sensative or highly specific tests. A sensative test will show alot of false positives and a specific test will show alot of false negatives. To have a test that is not only highly specific but is also sensative would likely take ALOT more blood and be VERY expensive so they chose one or the other. They'd rather have false positives then false negatives because if one kid slips though the cracks they will be left severely brain damaged. Only 1% of babies fail the pku and of those babies only 10% of them actually have pku. That's not a bad rate. It just sucks to be in the 1%. The good news is only 250 babies are born with PKU so it's really really unlikely he has it. I just have to not think about it.

[hapahaolegirl]

My son has PKU and is the only of my three kids with very pale skin and light eyes. If someone is not treated with a special low phenylalanine diet they can have lighter hair and eyes. Though light hair and eyes isn't the only or universal sign of PKU.

I'm surprised the retest is taking so long though. Within a few hours we had our results from the retest.

If your baby does have PKU you will most likely have to stop nursing for a week but then you can continue to breastfed and give your baby a special formula, alternating between the two.

I know the fear you are going through. It breaks my heart that you have to go through this right now and I hope you get results soon.

[fyrebloom]

Retest came back yesterday afternoon and he's normal. Phew!

[firewoman]

[reducereuserecycle]

[Therese's Mommy]

[boobs4milk]

[Serenyd]

Good news!