Lab reference ranges internationally

[Parksy]

Just out of pure interest does anyone know the lowest range of b12 deficiency where they start treating internationally. I know in UK it’s 150 and in Japan and Australia it’s 500. Quite a substantial difference.

[Nackapan]

Depends on what measurement they use too!

[helvella]

You can't just use numbers. The units matter as well.

For serum B12, some labs use pmol/L (picomole per litre) where others use pg/mL (picogram per millilitre) - and scaled versions thereof.

For Active B12, I think it is usual to use ng/mL (nanograms per millilitre).

[fbirder]

No, sorry that's not right. But don't worry, it's a common myth on Facebook.

It's a complete myth that they start treating at 500 in Japan. If they did then they would be treating 99% of their population. I'll bet a million quid that its similar in Australia.

Here is what the Japanese government say:

"If serum vitamin B12 levels are <200 pg/mL, vitamin B12 deficiency is very likely. If serum vitamin B12 levels are >300 pg/mL, vitamin B12 deficiency is unlikely." ncbi.nlm.nih.gov/pmc/articl...

Here is a man in a white coat telling you that 500 is the lower limit in Japan - and Europe. clancymedicalgroup.com/vita... Now we know that statement is a lie because we are in Europe.

There are no international standards. There are no national standards.

In the UK, Hull and East Yorkshire say that anybody below 115 pmol/L is deficient. In West Sussex you need to be below 180 ng/L (about 135 pmol/L). In Birmingham you need to be below 80 pmol/L to definitely be deficient and below 150 pmol/L for a possible deficiency.

[deniseinmilden in reply to fbirder]

Kindly and clearly put - thank you!

[Parksy]

Thank you all

[Forensic6]

The most up-to-date advice [See NICE on B12 and folic acid deficiency ] on diagnosing B12 deficiency as is that the levels of serum Billy 12 are not to be trusted because they frequently look normal but in fact the patient has the deficiency. What is currently recommended is that if the clinical picture suggests B12 deficiency, then a trial of treatment should be given to test if there are any positive changes supporting the diagnosis . If there are positive changes then the treatment can be continued .

It is still true that if the blood film shows macrocytes or the serum B12 is very low according to the laboratory which does the test, then it is highly probable that there is B12 deficiency. The reverse is not true. Absence of macrocytes or normal serum B12 levels does not rule out B12 deficiency.