Comparison of Diagnostic Accuracy of Active B12 (Holotranscobalamin) and Total Vitamin B12 (Cobalamin) and Verification of Active B12 Test
Poonam M Pal
Citation Information :
Pal PM. Comparison of Diagnostic Accuracy of Active B12 (Holotranscobalamin) and Total Vitamin B12 (Cobalamin) and Verification of Active B12 Test. Indian J Med Biochem 2020; 24 (1):25-31.
Objective: This study is based on the comparison of the diagnostic accuracy of active B12 (holotranscobalamin) to total vitamin B12 (cobalamin) and verification of the active B12 test for clinical use. Materials and methods: We have considered 310 individuals (total, mean age 48 ± 15years) that includes 233 individuals with serum active B12 levels within the biological reference interval of 20.6–196.7 pmol/L (controls, mean age 47 ± 15 years) and 54 individuals with serum active B12 levels below 20.6 pmol/L (cases, mean age 46 ± 13 years). Results: Based on the study, we have found that the diagnostic accuracy of active B12 (holotranscobalamin) was found to be better than that of total vitamin B12 (cobalamin). The precision of active B12 testing was found to be comparable to the manufacturer's claim. The reference interval for active B12 was also found to be comparable to the manufacturer's claim. Conclusion: From the above study, active B12 assay was found to be a better means for detecting vitamin B12 deficiency in individuals, and also, this assay was found to be a better one to follow-up the vitamin B12 levels in the patients who are already vitamin B12-deficient. Clinical significance: Active B12 (holotranscobalamin) testing can be used as a secondary choice of test for the patients with total B12 levels within the gray-zone (100–400 pg/mL) or can be used as a primary choice of test for the diagnosis of vitamin B12 deficiency and the follow-up during its treatment.
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