A nutritional vitamin B12 deficiency develops in inadequate absorption, but he can also relate to vegans who do not use vitamin supplements. Due to the lack creates a megaloblastic anemia, damage to the white matter of the spinal cord and brain, and peripheral neuropathy. The diagnosis is usually to decrease serum levels of vitamin B12. The Schilling test provides insights into the etiology. Therapeutic Vitamin B12 is administered orally and parenterally. Folate (folic acid) should not be used as a substitute for vitamin B12 since it although the anemia relieves, but progress neurological deficits under folate.
The term “cobalamin” means devices with biological vitamin B12 activity. These components play a role in nucleic acid metabolism, methyl transfer, and in the myelin synthesis and repair. They are necessary for the formation of red blood cells (see table: sources, functions and effects of vitamins).
(See also overview of vitamins.) The term “cobalamin” means devices with biological vitamin B12 activity. These components play a role in nucleic acid metabolism, methyl transfer, and in the myelin synthesis and repair. They are necessary for the formation of red blood cells (see table: sources, functions and effects of vitamins). In the diet contained vitamin B12 is released in the acidic environment of the stomach and R protein (haptocorrin) bound. Pancreatic enzymes cleave on these B12 complex (B12-R protein) in the small intestine. Subsequently, the secreted by the parietal cells of the gastric mucosa intrinsic factor binds with vitamin B12. The intrinsic factor is necessary for absorption of vitamin B12, which takes place in the terminal ileum. Vitamin B12 in plasma is bound to the transcobalamins I and II. Transcobalamin II function, vitamin B12 has to be transported to the body’s tissues. The liver stores large amounts of vitamin B12. A reabsorption in the liver keeps vitamin B12 back in the body. The vitamin B12 stores the liver to meet the physiological needs about 3-5 years when the intake of vitamin B12 is lacking (eg. As in individuals who eat vegan), and for months or up to a year if no capacity for the reabsorption enterohepatic are available. Large amounts of vitamin B12 do not seem to be toxic, but are (i. E. As a general tonic) for regular use is not recommended. Vitamin B-12 deficiency A nutritional vitamin B12 deficiency develops in inadequate absorption, but he can also relate to vegans who do not use vitamin supplements. Due to the lack creates a megaloblastic anemia, damage to the white matter of the spinal cord and brain, and peripheral neuropathy. The diagnosis is usually to decrease serum levels of vitamin B12. The Schilling test provides insights into the etiology. Therapeutic Vitamin B12 is administered orally and parenterally. Folate (folic acid) should not be used as a substitute for vitamin B12 since it although the anemia relieves, but progress neurological deficits under folate. Etiology of vitamin B12 deficiency can be the result of Inadequate supply Inadequate absorption Reduced use of certain medicinal Inadequate intake of vitamin B12 is possible in vegans, but otherwise unlikely. Still Children vegetarian mothers can develop a vitamin B12 deficiency at the age of 4-6 months, because the memory of the liver (which normally are considerable) are limited in these babies and their rapid growth due to a high demand. Inadequate vitamin B12 intake is the most common cause of a deficiency (see Table: Causes of vitamin B12Mangels In elderly patients, inadequate absorption resulting most often from a reduced acid secretion in these cases crystalline vitamin B12 is absorbed from vitamin supplements, but.. vitamin B12 present in the food is not released into the normal range and absorbed an inadequate absorption occurs in the case of a blind loop syndrome (with excessive bacteria growth) or an infection with the Fischbandwurmauf;. doing bacteria or parasites use the recorded vitamin B12, which can be absorbed only in smaller quantities so. inadequate vitamin B12 absorption occurs when the resorption of Ileunes destroyed by inflammatory bowel disease or were surgically removed. Less common causes of inadequate vitamin B12 absorption are a chronic pancreatitis, Ad ipositas- or gastric surgery, malabsorption syndromes, AIDS, the use of certain drugs such as antacids or metformin, repeated contact with nitrous oxide and an inherited disorder that leads to malabsorption in the ileum (imerslund-gräsbeck syndrome). Less common causes decreased utilization of vitamin B12 or use of certain medications a vitamin B12 deficiency (see Table: Causes of vitamin B12Mangels). The symptoms of pernicious anemia is often used interchangeably with a vitamin B12 deficiency. However, pernicious anemia refers specifically to anemia due to vitamin B12 deficiency, which was triggered by an autoimmune metaplastic atrophic gastritis with loss of intrinsic factor. Patients with classic pernicious anemia, which affects the most younger adults are at an increased risk of gastric cancer and other cancers gastroinstestinale. Causes of vitamin B12Mangels cause Source Inadequate nutrition Vegan Diet breast feeding by mothers who pursue a vegan diet fad diets Impaired absorption lack of intrinsic factor (with autoimmune metaplastic atrophic gastritis, destruction of the gastric mucosa, after gastric surgery or gastric bypass surgery) Inhibition the intrinsic factor decreased acid secretion intestinal diseases (eg. as inflammatory bowel disease, celiac disease, cancer, biliary or pancreatic diseases) competition for vitamin B12 (dur ch fish tapeworm infestation or blind-loop syndrome) AIDS Inadequate utilization enzyme deficiencies liver damage anomalies of transport proteins drug metformin antacids nitrous oxide (repeated exposure) symptoms and complaints Anemia usually develops insidiously. It is often more difficult than can recognize the symptoms because their slow progression allows a physiological adaptation. Occasionally, splenomegaly and hepatomegaly develop. Various gastrointestinal symptoms such as weight loss and abdominal pain localized hardly occur. Glossitis, which is described as “burning on the tongue”, is rare. Neurological symptoms occur regardless of the hematologic abnormalities and often without them. Subacute combined degeneration referred to degenerative changes in the nervous system due to vitamin B12 deficiency; The changes relate mainly to the white matter of the brain and spinal cord. Demyelinating or axonal peripheral neuropathies can occur. In early stages, the decreased perception of the position and vibration stimuli in the extremities of little to moderate severe fatigue and hyporeflexia is accompanied. In later stages it comes to spastic paralysis, reactions during Plantarextension, stronger precipitating the position and vibratory sensation in the lower extremities and ataxia. These deficits may develop as hand-foot syndrome. Tactile, pain and temperature sensation are usually not affected, suggesting, however, is difficult to determine in the elderly. Some patients react irritated and with mild depression. In advanced stages, paranoia, delirium, confusion and sometimes attitude hypotension show. The confusion is heavy with age-related dementias, such as Alzheimer’s disease abzugrenzen.Diagnose blood status and vitamin B12 and folate levels Partial Methylmalonsäurespiegel or Schilling test, it is important to remember that a severe neurological disorder can occur even without anemia or macrocytosis. The diagnosis of a vitamin B12 deficiency is found from the blood status and vitamin B12 and folate levels. The CBC reveals a megaloblastic anemia usually. Tissue damage and macrocytic indexes preceded anemia. A vitamin B12 levels <200 pg / ml (<145 pmol / l) points to a vitamin B12 deficiency. The folate levels is determined as a vitamin B12 must be distinguished from folate deficiency as a cause of megaloblastic anemia; a Folatergänzung may hide a vitamin B12 deficiency and alleviate megaloblastic anemia, but a progression or even an increase in neurological deficits not prevent it. If clinical evidence of vitamin B12 deficiency are present, but the vitamin B12 values ??are in or just slightly below the standard (200 to 350 pg / ml, 145 to 260 pmol / l) or hematological indices are normal, can further tests are performed. They include the following measurements: Methylmalonsäurespiegel in serum: increased Methylmalsäurespiegel in the serum supports the diagnosis of a vitamin B12 deficiency, but it can also occur in renal failure. The MMA levels also serves to monitor the treatment progress. MMA levels remain normal for folic acid deficiency. Homocysteine ??levels: values ??may be elevated in both vitamin B12 and folate deficiency in one. Less frequently, the value for Holotranscobalamin II (transcobalamin II-vitamin B12 complex): If this is <40 pg / ml (<30 pmol / l), is a vitamin B12 deficiency. After the vitamin B12 deficiency was diagnosed, additional tests (eg. B. Schilling test) are indexed, but not usually for the elderly to younger adults. Only when the dietary intake of vitamin B12 is obviously insufficient, the Serumgastrinspiegels or autoantibodies to intrinsic factor should be measured; the sensitivity and specificity of these tests are schwach.Schilling Test The Schilling test is only useful when it is important as with the classic pernicious anemia to detect a lack of intrinsic factor. For most older people there is no need to perform the test. With the Schilling test, the absorption of free radiolabeled vitamin B12 can be observed. Here radiolabeled vitamin B12 is administered orally, 1-6 h after follow 1000 mcg (1 mg) Vitamin B12 parenterally. So that the liver takes up less radiolabeled vitamin B12. Absorbed radioactive vitamin B12 is excreted in the urine is collected over 24 hours. The precipitated amount is measured and determined the percentage of the radiolabeled vitamin B12. Is the absorption within the norm, the urine contains ? 9% of the administered dose. Decreased excretion of <5% with normal renal function indicates an inadequate vitamin B12 absorption. An enhanced absorption with the subsequent addition of intrinsic factor to radiolabeled vitamin B12 confirms the diagnosis of pernicious anemia. The test is difficult to perform or evaluate because the urine is often not fully collected or renal insufficiency. In addition, the protein-bound Vitamin B12 is not detected in the Schilling test. Therefore, he gives no indication of a faulty release of vitamin B12 from foods, which is common in the elderly. The Schilling test fills the vitamin B12 depots again and concealed a defect. That's why he should be performed only after completion of all diagnostic tests and therapeutic trials. Is a malabsorption found the Schilling test can be repeated after trying the two-week taking an antibiotic. Eliminates the drug malabsorption, the cause is probably an excessive growth of bacteria in the gut (eg. As in blind loop syndrome) .Therapie vitamin B12 supplements of vitamin B12 can patients neurological neither a distinct lack even under severe symptoms suffer, given orally at a dose of 1000-2000 mcg. A Nasengelpräparat with vitamin B12ist at a higher price available. The high oral dose is absorbed even by mass action when the intrinsic factor is missing. MMA mirrors used to monitor the success of therapy decreases not, the patient does not take a vitamin B12 may. In more massive shortage 1 mg of vitamin B12 for several weeks i.m. 1- injected to 4 times a week until the abnormal blood levels are balanced; then goes administration of the vitamin once in a month. Although the blood test results usually within 6 weeks again reach the normal range (the reticulocyte count should get better within a week), it takes much longer for the neurological symptoms disappear. Neurological symptoms that keep for months or years, are irreversible. For most older people who suffer from vitamin B12 deficiency and dementia, the cognitive no longer increases after therapy. A vitamin B12 therapy must be continued for life, unless the pathophysiological processes that are crucial for the defect, can be eliminated. Children vegan mothers should erhalten.Wichtige from birth vitamin B12 supplements points Common causes of vitamin B12 deficiency is inadequate intake (z. B. in vegans), impaired absorption, age-related reduced acid secretion and autoimmune metaplastic atrophic gastritis (leading to pernicious anemia leads). The lack often leads to megaloblastic anemia, loss of awareness of the position in space and for vibration (this happens earlier and stops) and, in advanced stages of paranoia, delirium and confusion. To determine the blood count, vitamin B12 and folate levels. In adults, young and middle-aged who have been affected by the vitamin B12 deficiency, the Schilling test is to be performed. The treatment consists of the administration of vitamin B12 supplements.