Cap rast test results.......??????

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My sons allergist called back today with his cap rast tests for peanut and dairy......peanut was 4.13 and dairy was 1.19. I'm still not really clear what the numbers mean, though she felt the numbers were low enough to schedule food challenges for both ( he has only ever reacted with eczema, although i don't believe he has ever eaten any peanut, only ingested it through my breastmilk.) If anyone has an opinion to voice on this, I would like to hear it.....I have read many of you won't risk a food challenge esp. with the peanut. Alos , if someone has a better explanation of what the numbers mean, to get me through til my sons appt when I can ask more questions! thanks, Jennifer

On Jul 16, 2001

Ask for a hard copy of the results. I know when I had my son's RAST test done I had no idea what a 3 was until I got the hard copy and saw that he was a 3 out of 6. Also there was a more detailed explaination of the results on it.

On Jul 16, 2001

jayD, this is from an email from FAAN a while back. I had emailed them to ask about cross-reactivity, and they sent me an email with a lot of information. ------------------------------------------- The level of specific IgE antibody measured using a particular method of RAST test (CAP-RAST FEIA) reported in units called kUa/L, which indicates a concentration of specific IgE) was recently reported to be useful in determining the chance of true reactivity to certain foods. For example, an IgE antibody level of over 6 kUa/L to egg, over 32 to milk, over 15 to peanut, and over 20 to codfish were highly predictive (greater than 95% chance) of having some type of allergic reaction among highly allergic children. Unfortunately, lower values, unless virtually undetectable, may still indicate a potential for having an allergic reaction. This test may prove useful in following levels of particular IgE antibodies over time to see if they are falling (perhaps indicating that the allergy is being outgrown). -------------------------------------------

So according to this, your son's number for peanuts seems low. However, if I remember correctly, your son is young--only 20 months right? I know I have a friend with a daughter who is 2 1/2. Her CAP RAST for peanuts went lower until it was considered negative. However, the allergist, who is one of the best in the country for PA, will not challenge her until she is 4 or 5 and her immune system settles down. I would keep your son off peanuts until he is older. Have the CAP RAST repeated to make sure it is still low, or even going down more, and have him challenged when he is older. On the other hand, if he is challenged now and doesn't react, that would be nice to know! But while he is young, especially since he appears to have multiple food allergies, I would keep him away from all nuts.

On Jul 16, 2001

Double post.

[This message has been edited by BENSMOM (edited July 16, 2001).]

On Jul 16, 2001

Good luck as you go down the challenge path...My 5 year old son today had a negative skin test today for peanuts and then had blood drawn for a CAP RAST. We should have the results in a couple of weeks. We're hopeful. He had a vomiting reaction to peas and beans at age one, and showed a positive skin reaction to peanuts, but he's never actually eaten them. We have always been hyper-vigilant! We too are deciding what to do if the CAP RAST comes back low. As much as it frightens me, I think we'll do the challenge at our Dr's office. We trust our Dr. a great deal and he is very aware of current research and a fan of Dr. Sampsons. While I'd alway's planned on Cory's allergy being a lifelong thing, it would be nice to not have to be afraid every time he goes to school, a resaurant, to a birthday party, camp, etc. I doubt we'd ever become a very big peanut consuming household, but we'd like to experience....dare I say it?.....normalcy for a change.

On Jul 16, 2001

JayD I have to agree with Bensmom. I would wait to challenge the baby. They are now suggesting that you do not introduce highly allergenic food before the age of 3 or even 5. Eventhough the number is low I personally would be concerned about giving a food challenge so early because the baby can't even really tell you what they are feeling. Bensmom is correct that anything over 15 for peanut is considered a very high positive, so keep your fingers crossed and hope for the best but wait to be on the safe side. I would rather err on the side of caution than regret a choice I could have put off for a little while. I'm sure you will do what you feel is best and what you are comfortable with. My son had a CAP RAST done 3 weeks ago. His came back a 51.89 which is a class 5 bordering a class 6. Well looks like we need to keep up the vigilence. Good Luck! Fran [img][/img]

[This message has been edited by BCUZILUVHIM (edited July 16, 2001).]

On Jul 17, 2001

Fran, I saw a chart recently that had a Class V as 50-100, Class 6 was over 100. If your child was a low 50's he is just barely a Class V and nowhere near a Class VI. Not that it matters much - Class V is very serious.

On Jul 17, 2001

Hi Philips Mom! This is EXACTLY what my doctor sent to me. From his mouth to my ears he said he was a 5 bordering a 6. This is the report. "Fran, as discussed these results are consistent with a significant elevation in antibodies to peanut. Dr XXXXX"

F013 PEANUT 51.89 IU/mL CLASS V 12.51-62.50

Levels of Specific IgE mRAST IU/mL CLASS <0.05 0 0.05-0.07 0/I 0.08-0.15 I 0.16-0.50 II 0.51-2.50 III 2.51-12.50 IV 12.51-62.50 V 62.51->100 VI

This test was performed at LABCORP in Burlington NC. The allergist said that it depends on what lab you use, what chart they follow. I have seen the chart you are refering to but they did not use that one for my sons test. So be sure to get any results in writing with the chart. I am here to support the poster of this thread and not to draw attention to my own drama. Lets support each other and not negate each other. I don't like playing the "feel sorry for me" or "my kid is worse than your kid" game. Anyone who knows my posts knows that I treat this allergy as a matter of daily life and it shouldn't matter what the class is because it doesn't show HOW the child will react as Bensmom so wonderfully brought to my attention; only that there is a 95% chance that they will react. The doctor I was on the show last week with also supported this. It doesn't matter the class it only matters that we have to keep our kids safe. Remember we are all in this boat together. Debating whether someone is one class or another shouldn't be an issue so for that I am sorry to post this chart but I felt as if I was being questioned and acting as if my kid is gonna croak tommarrow.

Gee, I'm sounding a little like another beloved poster who is taking a summer break!?! Hmm guess she has rubbed off on me which I think is actually a good thing! Be Well! Fran [img][/img]

HEY!! WAIT A MINUTE!! The more I study these results, the more I realize I think they sent the request for banana for IgE conc (kU/L)and not the peanut!!!!! The peanut was done in NC and the banana was done in KS the peanut as you see is in IU/mL and not in kU/L but it says on the report that this is the Pharmacia & Upjohn ImmunoCAP allergen-specificIgE system???!!!? Gotta go gonna call the allergist right now. [img][/img]

[This message has been edited by BCUZILUVHIM (edited July 17, 2001).]

On Jul 17, 2001

Thank everyone SO much for all of your input! I was able to have a lengthy conversation with Brads allergist Monday night, and we decided to wait until he is close to 3 before trying him on Dairy again ( that is about the age I outgrew my dairy allergy), and we will wait until before he starts school ( he will be almost 6 by then) to do a peanut challenge with him. She said they likely won't retest on either of these with scores this low, and she was very encouraged. He goes in next month for an egg challenge test, as he did not have a positive skin reaction on his 2nd skin prick test. She said I could try the wheat in a year or so too...he probably will keep that one a few years . I am so grateful that there are so many positive things we can do for our kids allergies these days, between the testing and treatments. I suffered with such horrible eczema as a kid, and my parents really worked hard to find treatments for me but nothing ever seemed to work,( the worst were humiliating ultra violet light treatments on my rashy bottom...nothing like having a stranger shine a light on your nakie bum for 30 minutes every week! and Balnatar baths....ick! I was always yellow, and smelled like sulpher) and the testing was so limited....I am sure I was allergic to many other things than what those tests showed. tonight, when my daughter broke out in a rash from the chocolate she sneaked at grandmas today, all I had to do was rub a little elocon on it, give her claratin , and she was sleeping easy! I am so glad for them. Thanks again, Jen

On Jul 18, 2001

Ahhh Jen, eventhough I am not your babys' momma I just sighed a breath of releif. I am so glad that you and the doctor chose to wait. You have been following precautions this long, in the scheme of things it is not that much longer to wait. I regret many things I did and did not do when my son was a baby which I know for a fact exhaserbated his allergies and I will never forgive myself for it. I have to move forward and there is nothing I can do to change it now. By the way called the allergist back and forth etc. the lab switched the Rx and did immunocap for banana and rast for peanut that is why I have the results listed as I do above. The lab still has his serum and will be performing the immunocap for peanuts and no additional charge since they made a booboo.

So glad again to hear everything is well and I am sure this is the best choice!! Be well! [img][/img]