Severe Hypernatremia Caused by Acute Exogenous Salt Intake Combined with Primary Hypothyroidism

This report describes a case of severe hypernatremia with a serum sodium concentration of 188.1mmol/L caused by exogenous salt intake. A 26-year-old man diagnosed with Crohn's disease 5 years previously visited our clinic due to generalized edema and personality changes, with aggressive behavior. He had compulsively consumed salts, ingesting approximately 154 g of salt over the last 4 days. Despite careful fluid management that included not only hypotonic fluid therapy for 8 hours but also hypertonic saline administration, his serum sodium level decreased sharply at 40.6 mmol/L; however, it returned to normal within 72-hour of treatment without any neurological deficits. Primary hypothyroidism was also diagnosed. He was discharged after 9 days from admission, with a stable serum sodium level. We have described the possibility of successful treatment in a patient with hypernatremia caused by acute salt intoxication without sustained hypotonic fluid therapy.