Status of the determination of magnesium in mononuclear blood cells in humans.

The determination of magnesium in mononuclear blood cells (MBC) as an index of intracellular magnesium was proposed 10 years ago. Studies to date show relatively good agreement among investigators for the mean value of magnesium in MBC. The MBC magnesium value does not show a significant correlation with either serum or red blood cell magnesium concentrations in humans. However, there may be a correlation for magnesium between MBC and muscle and for magnesium and potassium in MBC. Studies suggest a clinical utility for the MBC magnesium in several disease entities.