La B12 c'è, ma non funziona

The paper reports the typical case and clinic of a defect in B12 metabolism. Such diseases, which are rare, mimic B12 intake or absorption deficits (crasis alterations, mixed neuropathy) but are distinguished first and foremost by the presence of normal B12/folate levels in contrast to high levels of the 'sentinel metabolites' (homocysteine and methylmalonic acid). A history of global retardation of acquisitions and poor growth may make the diagnosis more suggestive.