Zinc unbound concentration as an anchor to drive individualize repletion.

Background And Aims: Zinc (Zn) quantification is of particular interest in many clinical condition (e.g. inflammatory disease, critical care). Currently, Zn status is assessed by measuring plasma/serum concentration. This concentration corresponds to the sum of unbound Zn (Zn-C) and Zn highly bound to albumin (Zn-C).

Methods: Using a pharmacokinetic approach to the interpretation of total Zn concentration (Zn-C), taking into account Zn-C and the influence of hypoalbuminemia on Zn-C, it is possible to improve the individualization of Zn repletion.

Results: Therefore, during pregnancy and in certain inflammatory disease situations, repletion may not be necessary. However, as in critical care, it would be more appropriate to perform Zn-C assays to improve Zn repletion.

Conclusion: Coupled total and unbound Zn should be monitored in order to individualize Zn repletion.