Pathological consequences of excess Vitamin B 12 ?
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Hello, I am 19 years old. I did some blood examination as consulted by my physician. I have been diagnosed with excess vitamin B12 in my blood. I used to take vitamin supplements 3 months back. But I discontinued. Still it has reflected in the test. What should I do now? Does it indicate any other disorder? What are all the pathological consequences of excess Vitamin B 12 ?
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@santanu Vitamin B12 is a ubiquitous coenzyme mainly involved in reactions leading to the synthesis of DNA and of that of methionine from homocysteine. This explains, on the one hand, the haematological, neurological and epithelial clinical manifestations observed during vitamin B12 deficiency, and on the other hand, the plasma accumulation of substrates of enzymatic reactions involving vitamin B12, namely methylmalonic acid and homocysteine. Contrary to vitamin B12 deficiency, the pathophysiology and clinical consequences of high serum cobalamin have, until now, been very little studied. It is however currently considered that an increase in plasma levels of vitamin B12 may be an indicator of a functional deficit with clinical consequences paradoxically similar to those of vitamin B12 deficiency. Indeed, an increase in the binding of vitamin B12 to HCs, secondary to an elevation in their plasma levels (especially for TCB I and III which are by far the majority), leads to a potential decline in its attachment to TCB II and therefore alters its delivery to the cells. Thus, a functional deficit in vitamin B12 with an increase in homocysteine and/or methylmalonic acid levels can occur, even though the initial anomaly in this instance is not a deficiency in vitamin B12. Beside by this mechanism, functional deficiency may also be caused by the failure of damaged liver to take up cobalamin from the serum and/or by leakage of total vitamin B12 from the liver tissue into the plasma.