Perchloric acid treatment to stabilize uric acid concentrations in blood samples of patients receiving uric acid oxidase (rasburicase) therapy.

our findings is that the concentration of HC is influenced by the vitamin B12 status of the patient. The issue has important implications for the interpretation of low cobalamin in relation to low HC concentrations in patients undergoing examination for vitamin B12 deficiency. If genetic factors were the only regulators of the HC concentration, the physician could decide that the low concentration of cobalamins reflected an inherited low HC. If HC is regulated by the vitamin B12 status in addition to the genetic factors, as suggested by us, such a patient should always undergo further analysis to rule out a deficiency state.