Vitamin B12, Plasma (LAB67)

Vitamin B12 (Cobalamin) is a water-soluble vitamin essential for various cellular functions, including DNA synthesis, amino acid synthesis, and fatty acid metabolism. It plays a crucial role in nervous system function through myelin synthesis and red blood cell maturation. Vitamin B12 was initially identified due to its clinical association with pernicious anemia. Deficiency can lead to a range of symptoms, including anemia and neuropathy.

Screening for vitamin B12 deficiency is recommended only if specific risk factors are present. These include gastric or small intestine resections, inflammatory bowel disease, prolonged use of metformin or proton pump inhibitors/histamine H2 blockers, strict vegan or vegetarian diets, and adults older than 75 years.

While direct measurement of vitamin B12 can indicate deficiency, other laboratory tests, such as homocysteine and methylmalonic acid, can be more sensitive in detecting early and functional deficiencies.

• Measuring vitamin B12 for routine screening without specific indications can lead to unnecessary interventions and healthcare costs without improvements in care.

• Only order vitamin B12 measurement for patients with specific risk factors or clinical indications of deficiency.

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