Excessive hypernatremia in a patient with renal amyloid disease

A 24-year-old Italian male presented with a nephrotic syndrome in September 1984. In February 1985 renal biopsy showed amyloid disease with tubular atrophy and interstitial fibrosis. Edema was treated with furosemide, and cholchicine was started. Because he feared side effects of drug therapy, the patient stopped all medication by July 1985. Instead, he decided to restrict severely fluids in order to fight edema. In early November 1985 his family noted he was becoming increasingly lethargic. Two weeks later, on his admission to the hospital, he had a serum sodium concentration of 193 mmol/l and serum osmolality of 397 mosm/kg. Apart from mild mental status changes neurological examination was normal. The fluid deficit was slowly corrected. He was discharged three weeks later with normal serum electrolytes. This case demonstrates that (1) severe hypernatremia can present with mild neurological symptoms and (2) it can be survived provided that it develops slowly and is corrected cautiously.