Test Database

Description

cB12 (combined indicator of B12 status) previously known as “wellness score” is a rigorously derived mathematical model combining all four markers (total B12, holotranscobalamin (holoTC, Active-B12), homocysteine and methylmalonic acid (MMA) which makes adjustments for age and folate status. Serum total B12, holoTC, serum/plasma homocysteine, serum MMA and folate results are normally required to calculate cB12. Formulas using two or three markers are also available. Due to the relocation of the Nutristasis service to the Blackfriars Hub site, this test is not currently accredited by UKAS to ISO15189

Clinical details

cB12 has been suggested as a more reliable indicator of vitamin B12 status than the individual tests. Depending on the cB12 value obtained, B12 status is classified as: elevated, adequate, low, possible B12 deficiency and probable B12 deficiency. The score has been validated against 5000+ patients and the diagnostic cut-points are validated against the clinical outcomes of hemoglobin and cognitive scoring.

Related condition

Pernicious anaemia, malabsorption, vitamin B12 deficiency

Reference range

< -2.5                probable vitamin B12 deficiency;

-2.5 to -1.5         possible vitamin B12 deficiency;

-1.5 to -0.5         low vitamin B12;  

-0.5 to 1.5          adequate vitamin B12;  

>1.5                   elevated vitamin B12

 

Synonyms

Fedosov score, wellness score, vitamin B12 status assessment

Testing site

Synnovis : Reference Services : Blackfriars Hub

Laboratory

Nutristasis Unit