We report a case in whom slow correction of
hyponatremia (5 mmol/day for 3 days) induced
central pontine myelinolysis (CPM). After the diagnosis was confirmed by imaging, we started to relower serum Na that completely recovered the sign and symptoms of CPM. Rapid correction of serum
sodium is known to be associated with CPM. However, it may occur even after slow correction of
hyponatremia. Currently, there is no standard
therapy for CPM other than supportive
therapy. Other
therapy includes sterioid, plasmaphresis and
IVIG, but these
therapies have not been shown to be particularly effective. The pathophysiology of CPM is related to a relative
dehydration of the brain during the correction of
hyponatremia, resulting in cell death and
demyelination, therefore gentle
rehydration with lowering serum
sodium may not be an unreasonable
therapy. The present case provides supportive evidence that reinduction of
hyponatremia is effective in treating CPM if started immediately after the diagnosis is suggested. The present case tells us that severe chronic
hyponatremia must be managed with extreme care especially in patients with chronic debilitating illness and that relowering serum Na is a treatment of choice when CPM is suggested.