Changes in manganese content of mononuclear blood cells in patients receiving total parenteral nutrition.

We measured the manganese content of mononuclear blood cells and the manganese concentrations in whole blood and plasma from 31 healthy volunteers and 25 patients receiving total parenteral nutrition (TPN) (i.e., no dietary manganese). The manganese content (mean +/- 2 SD) of mononuclear blood cells and the manganese concentration in whole blood and plasma in the healthy volunteers were 8.84 +/- 4.18 ng/10(8) cells, 11.21 +/- 4.68 micrograms/L, and 1.21 +/- 0.72 micrograms/L, respectively. The manganese content of mononuclear blood cells from patients receiving TPN gradually decreased, falling below the lowest limit of the normal range by 21 weeks (95% confidence limits, 13-30 weeks) after starting TPN. Manganese concentrations in whole blood and plasma were within normal limits during our study period. These results suggest that the manganese content of mononuclear blood cells may better indicate manganese nutritional status than whole-blood or plasma concentrations.