Total corrinoid, cobalamin (vitamin B12), and cobalamin analogue levels may be normal in serum despite cobalamin in liver depletion in patients with alcoholism.

Serum, erythrocyte, and liver levels of total corrinoids, cobalamin (vitamin B12), and cobalamin analogues were determined by differential radioassay in 27 patients with alcoholism. Compared with normal subjects, liver content of total corrinoids and cobalamin in alcoholics was low. Conversely, serum total corrinoids and cobalamin were high. Compared with normal, levels of erythrocyte cobalamin analogue in alcoholics were elevated, but levels of cobalamin were not. Analogues in liver represented a similar percentage of total corrinoids in alcoholics as in normals. The data confirm prior work suggesting that, in alcoholism and in liver disease, cobalamin depletion in tissues may be masked by normal to high serum cobalamin and analogue levels. The failure of damaged liver to take up from the serum cobalamin and analogues, compounded by release of these compounds and their binders from damaged liver into the serum, can account for these findings.