Misleading Reductions of Serum Sodium and Chloride Associated with Hyperproteinemia in Patients with Multiple Myeloma

Does extreme elevation in concentration of human blood serum proteins undermine the validity of conventional units of expression of concentrations of sodium and chloride in clinical biochemistry? The foregoing study has yielded an affirmative answer and emphasizes the validity of millimolality (e.g., mM Na per kg serum water) in contrast to the misleading interpretations which may derive from use of millimolarity (mM of Na per liter of serum). The ultrafiltrability of sodium and potassium, in preliminary studies, is consistent with predictions based upon Gibbs-Donnan equilibrium.