schilling test

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ohyeahbaby

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this whole schilling test thing is going over my head.

you give radio-labelled b12 orally and you give unlabeled b12 intramuscularly. The IM injected B12 will saturate your B12 receptors on the liver. Therefore, if you are normal, you will absorb the radiolabeled B12, but since you're saturated, you will pee it out and we can see it in your urine.

However, if you are having trouble absorbing B12, then there will be LESS radiolabeled B12 in your urine? WTF? is there something I'm missing? where did that radiolabeled B12 go then if you're not absorbing it? you're having trouble ABSORBING the B12, so you're supposed to pee it out, no? i would expect to find more radio-labelled B12 in the urine if the dude is not normal.

Hell, if I were to make my own test, I would skip all this crap, give the dude an X amount of radiolabelled B12 orally. If the dude is having trouble absorbing it, then I expect to find the exact same value of X in his urine. If he's not having trouble absorbing it, then I will find an amount of radiolabelled urine that is less than X in his urine.

There's gotta be something I'm missing.

Please help me! Thank you in advance.
 
Here is my understanding of the Schilling Test:

In the first part, you give radiolabeled B12 + intramuscular B12 injection: the IM form is given to help replenish the B12 stores in the body. By doing so, if radiolabeled B12 is absorbed, it will eventually be excreted and detectable in the urine.

Presence of radiolabeled B12 in the urine is indicative of B12 deficiency.

If the results from the first part are inconclusive (aka) there is no urinary B12, that suggests there is a problem with absorption of vitamin B12, which is why it didn't show up in the patient's urine.

So now in the second part of the test you have to give radiolabeled B12 with IF:
-- If you detect B12 in the urine, it means the patient was deficient in IF. This is because in this test you just gave them B12 + IF and only NOW are you seeing B12 in the urine.

-- If you do not see B12 in the urine, then this indicates the problem is not with lack of B12 or lack of IF. The problem is with absorption in the GI tract.
 
Here is my understanding of the Schilling Test:

In the first part, you give radiolabeled B12 + intramuscular B12 injection: the IM form is given to help replenish the B12 stores in the body. By doing so, if radiolabeled B12 is absorbed, it will eventually be excreted and detectable in the urine.

Presence of radiolabeled B12 in the urine is indicative of B12 deficiency.

If the results from the first part are inconclusive (aka) there is no urinary B12, that suggests there is a problem with absorption of vitamin B12, which is why it didn't show up in the patient's urine.

So now in the second part of the test you have to give radiolabeled B12 with IF:
-- If you detect B12 in the urine, it means the patient was deficient in IF. This is because in this test you just gave them B12 + IF and only NOW are you seeing B12 in the urine.

-- If you do not see B12 in the urine, then this indicates the problem is not with lack of B12 or lack of IF. The problem is with absorption in the GI tract.

thank you for taking the time to answer, but futuredoctor10 said exactly what I was looking for. Been studying so long, and i'm out of it.

If you do not absorb the radioactive B12, then it goes out with #2... in the feces!

WOW...I am an idiot. Looks like all the explanations out there didn't say that it goes into the feces because they assume I have a grasp of 4th grade biology. I would like to think it's because I haven't slept in a while. At least I hope so. Thank you!!!!!!😍
 
I might as well go ahead and ask this since I already look like an idiot:

notice how in FA they say that B12 it's primarily synthesized by microorganisms. Then why do we care about what our intake is if we have microorganisms making it for us? since meat for example has B12, do they mean that B12 is synthesized in animals by these microorganisms?

One last Q: besides B12 and vit K, is there anything else I need to know about that's synthesized by microorganisms?

thanks again 🙂
 
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