Question 1

what is the most accurate blood test to check  b-12 levels?

Accepted Answer

Serum tests: B12 levels can be testing in the blood directly but I also order a methylmalonic acid level if I have high clinical concern.  This is elevated prior to B12 levels being low (could be normal range).  B12 is the cofactor for the enzymatic reaction involving methylmalonic acid so without B12 the MMA levels increase.  Then issue is why is one deficient in Vit B12?

Question 2

which has a higher accuracy level: a breathalyzer or a blood test?

Accepted Answer

Blood test: Simple question -- but with real-world implications that are anything but simple. Best wishes.

Question 3

which of the following accurately predicts problems with cortisol levels blood test, 24 hr urine or midnight saliva swab?

Accepted Answer

Depends: Blood cortisol is useful in the diagnosis of cushings (hypercortisolemia) or adrenal insufficiency.  A 24 hr urine cortisol is helpful to diagnose excess cortisol.  Saliva cortisol is only helpful in diagnosing excess cortisol, not adrenal insufficiency.  If a blood cortisol level is low, further evaluation is required to establish if your adrenal function is truly low.

Question 4

when is the best time to take valproate blood test  to be most accurate level? i take 750mg twice a day (at 12h intervals) depakote er. thanks

Accepted Answer

Trough level: Depakote ER is usually taken once a day because it is an extended-release formulation. Timing of the blood draw does matter. Speak to your prescribing physician regarding your dosing and blood work. Here is a relevant article with more specific information: http://www.ncbi.nlm.nih.gov/pubmed/16778728

Question 5

is a quantitative blood test accurate at 22 days after sex? my normal hcg level is 3. would it show if i was pregnant by 3 weeks after intercourse?

Accepted Answer

: Conception occurs within day or so of the sex. It takes about 3 weeks for the embryo to make enough HCG for a positive pregnancy test. Blood test may be done a day after a missed period, HCG more than 25 indicates pregnancy. Home pregnancy tests should be done 4-5 days after the missed period. If the result is negative repeat the test in 4-5 days. Use first morning urine.

Question 6

i have an irregular cycle. how many days after sex can i take an hcg blood test for accuracy? my level was 'less than 1.2' 13 days after intercourse

Accepted Answer

About two weeks: You can take a pregnancy test about two weeks after to determine if you are pregnant.

Question 7

37 yr old female very low iron in recent blood test.gp prescribed ferrous fumarate once a day.after 30 days she needs a ferritin test to check iron levels should she stop taking the tablets before blood test or carry on taking them want accurate test?

Accepted Answer

: I would continue to take the med until you are told to stop it. It often takes up to 3 months or more to restore the normal iron reserves to someone who is anemic. The med itself will not alter the test while you take it.

Question 8

i am of se asian origin blood test for sweats at night and tiredness result states the patient has variant hb prevents accurate measure of hba1c recommend serum fructosmine level to mon diabetes control.wbc 3.9 range 4-11 neutrophilis 1.3 r 2.0-7.5 ?

Accepted Answer

Variant hb: Abnormal hemoglobins can be a problem with diabetes management, as the Hgb A1C is not accurate.  You can try following the fructosamine (or glycated albumin), but it is not a very good test, and is often not helpful.  Better to follow fingerstick glu more carefully.

Question 9

could i have an ectopic pregnancy with hcg level too low for home pregnancy test even after 2 months? missed two periods, tested 6x negative. had blood test 3 week after first missed period, negative? would that blood test be accurate, or too soon ?

Accepted Answer

: Irregular menstrual periods are common. The fluctuations of estrogen and progesterone can be easily affected by stress, weight gain/loss, exercise, lack of sleep, thyroid problems, and uterine issues. If your period irregularities persist, talk to your Dr about what testing can be done to determine the cause. You are not pregnant, as tests at those dates are very sensitive.

Question 10

are blood test more accurate than clear blue?

Accepted Answer

Blood Test vs Urine: It would be better to say that the blood test is able to detect smaller amounts of the hCG that indicates pregnancy.  Urine home pregnancy tests are very accurate and also very sensitive, and they vary a bit brand to brand.    Once you have missed your period, either test would normally detect hCG these days.  Good luck!

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What is the most accurate blood test to check b-12 levels?

A member asked:

Which has a higher accuracy level: a breathalyzer or a blood test?

A member asked:

Which of the following accurately predicts problems with cortisol levels blood test, 24 hr urine or midnight saliva swab?

A member asked:

When is the best time to take valproate blood test to be most accurate level? i take 750mg twice a day (at 12h intervals) depakote er. thanks

A member asked:

Is a quantitative blood test accurate at 22 days after sex? my normal hcg level is 3. would it show if i was pregnant by 3 weeks after intercourse?

A member asked:

I have an irregular cycle. how many days after sex can i take an hcg blood test for accuracy? my level was 'less than 1.2' 13 days after intercourse

A member asked:

37 yr old female very low iron in recent blood test.gp prescribed ferrous fumarate once a day.after 30 days she needs a ferritin test to check iron levels should she stop taking the tablets before blood test or carry on taking them want accurate test?

A member asked:

I am of se asian origin blood test for sweats at night and tiredness result states the patient has variant hb prevents accurate measure of hba1c recommend serum fructosmine level to mon diabetes control.wbc 3.9 range 4-11 neutrophilis 1.3 r 2.0-7.5 ?

A member asked:

Could i have an ectopic pregnancy with hcg level too low for home pregnancy test even after 2 months? missed two periods, tested 6x negative. had blood test 3 week after first missed period, negative? would that blood test be accurate, or too soon ?

A member asked:

Are blood test more accurate than clear blue?

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