We report the case of a 62 year-old symptomatic patient with severe hypergl
ycemic hyperosmolality associated with hypernatremia. During treatment, the
progressive decrease in serum tonicity, which resulted in the amelioration
of the neurological symptoms, followed the decrease in serum glucose and m
ainly the corrected serum sodium levels rather than the decrease in the unc
orrected serum sodium levels. The case illustrates the usefulness of glucos
e - corrected serum sodium levels to monitor treatment in such conditions i
n order to avoid neurological consequences caused by the decrease in serum
osmolality.