The concentration of total vitamin B12 in serum is not a sufficiently sensitive or specific indicator for the reliable diagnosis of vitamin B12 deficiency. Victor Herbert proposed a model for the staged development of vitamin B12 deficiency, in which holotranscobalamin (HoloTC) is the first indicator of deficiency. Based on this model, a commercial immunoassay has been controversially promoted ...

Objective. To compare the prevalence of the vitamin B12 deficiency in geriatric diabetic patients treated with or without metformin. Methods. Records of 134 patients with diabetes mellitus (DM) aged 61 to 93 (mean, 80) years who were treated with (n=56) or without (n=78) metformin were reviewed. Patient demographics (age, gender, duration of DM, smoking status, alcohol consumption), medication ...

The role of vitamin B12 in the folate dependent biosynthesis of thymidine nucleotides is controversial. In an attempt to clarify this, three methods have been used to assess the relative efficacy of vitamin B12 (hydroxocobalamin) and various folate analogues in titrated concentrations at correcting 'de novo' thymidylate synthesis by megaloblastic human marrow cells: (1) The deoxyuridine (dU) su...

BACKGROUND Studies have shown a clear relationship between depressive disorders and vitamin B12 deficiency. Gastroenteritis and Helicobacter pylori infections can cause vitamin B12 deficiency. Helicobacter pylori infections are not uncommon among people of Turkish descent in The Netherlands. AIM To examine the frequency of vitamin B12 deficiency in depressive patients of Turkish descent and c...

Vitamin B12 is an essential micronutrient required for optimal hemopoetic, neuro-cognitive and cardiovascular function. Biochemical and clinical vitamin B12 deficiency has been demonstrated to be highly prevalent among patients with type 1 and type 2 diabetes mellitus. It presents with diverse clinical manifestations ranging from impaired memory, dementia, delirium, peripheral neuropathy, sub a...

Subacute combined degeneration ( SCD) due to vitamin B12 deficiency is common in North of Europe but sometimes it is seen in Iran. It can develop before the symptoms of anemia is obvious, with myelin injury and then axon and even neuron destruction in spinal cord, brain, optic and peripheral nerves. In this study two cases are reported; in the first patient, this disease in manifested by vitami...

Vitamin B12 deficiency is widespread. Among the population groups at risk are older people, vegetarians, pregnant women and patients with renal or intestinal diseases. The neurological symptoms of vitamin B12 deficiency are unspecific and can be irreversible. Early detection is therefore important. This article reviews the diagnostic performance of the different laboratory markers for vitamin B...

Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In...

conclusions demyelinating disease, anterior ischemic optic neuropathy, non-arteritic anterior ischemic optic neuropathy, autoimmune disease, and hereditary optic neuropathy could cause optic neuropathy. normal cbc parameters and the absence of clinical manifestations of vitamin b12 deficiency could not rule out its diagnosis. careful physical examinations and history-taking with a classical app...

Megaloblastic anemia is rare in infants and is generally due to vitamin B12 (cobalamin) deficiency in the mother. Neurologic symptoms of vitamin B12 deficiency include irritability, failure to thrive, hypotonia, and developmental regression/delay. Herein we present 2 infants with vitamin B12 that developed movement disorder 5 d after initiation of vitamin B12 treatment. Symptoms included tremor...