[Severe hypernatremia. Case report, pathophysiology and therapy]

Salty, Sweet and Difficult to Treat: A Case of Profound Hypernatremia in the Setting of Hyperosmotic Hyperglycemic State

Hyperosmolar hyperglycemic state (HHS) is a disorder that occurs most frequently in type 2 diabetics and is associated with high mortality - up to 50%. Hypernatremia, when associated with HHS, worsens the prognosis. Encephalopathy is evident at a serum sodium level greater than 160 mOsm/kg. Additional symptoms include lethargy, weakness, seizures, and coma. Rhabdomyolysis can rarely occur in hyperosmolar states. Here we describe a case of severe hypernatremia in the setting of HHS leading to profound encephalopathy and report to the best of our knowledge the highest serum sodium level published in the literature. A 50-year-old female with no past medical history (PMH) of diabetes presented to the ED obtunded and found to have a glucose level of 1400 mg/dL without metabolic acidosis or ketosis. Her sodium on presentation was 169 mOsm/kg but subsequently rose to 200 mOsm/kg when corrected for hyperglycemia. Plasma osmolality was 340 mOsm/kg. She developed pre-renal acute kidney injury (AKI) secondary to the osmotic diuresis from severe hyperglycemia as well as rhabdomyolysis with a peak creatine kinase(CK) level of 2493. The free water deficit was 14L which was corrected. New-onset anisocoria raised concern for osmotic demyelination which was further investigated with MRI. An acute ischemic stroke in the right caudate was found. Fortunately, the patient survived the endocrine emergency. This case emphasizes the importance of an appropriate rate of sodium correction. This case is particularly unique because the degree of hypernatremia seen here was in the absence of intentional salt loading (for example by the administration of hypertonic saline), or psychiatric disease (as psychogenic adipsia). In conclusion, we report the case of severe hypernatremia and the highest documented serum sodium level was seen in literature in the background of HHS, rhabdomyolysis and septic shock.