[Vitamin B12 deficiency in neurology]

Vitamin B12 is vital compound that can not be synthesized by human organism so it is completely dependent on input from environment. Cobalamin is involved in many important cell processes revealing his deficiency in many tissues. Etiology of vitamin B12 deficiency is various. This deficiency has epidemical proportions, especially in older population. Most frequent are neurologic, psychiatric, hematologic and gastroenterologic manifestations. Progression of untreated deficiency leads to progressively grave lesions, invalidity and possibly lethal outcome. Making right diagnosis is of utmost importance cause it can allow timely application of substitution therapy and prevention of irreversible damage.