Manganese (Mn) is a trace element that is an essential cofactor for several enzymes, including 1 form of superoxide dismutase and the gluconeogenic enzymes: pyruvate carboxylase and isocitrate dehydrogenase. It circulates in the serum as a metalloprotein complex with any of several proteins. The +2 and +3 states are of biological significance, but speciation in the analysis has not been studied sufficiently to determine its value. The required daily intake of 1 to 6 mg is readily supplied by a normal diet with a diverse mixture of fruits and vegetables.
Whole blood levels above the normal range are indicative of manganism. Values between 1 and 2 times the upper limit of normal may be due to differences in hematocrit and normal biological variation, and should be interpreted with caution before concluding that hypermanganesemia is contributing to the disease process. Values greater than twice the upper limit of normal correlate with disease. For longitudinal monitoring, sampling no more frequently than the half-life of the element (40 days) should be used.
- Sample of blood serum
- We perform the test upon request