2009 Southern Regional Meeting Abstracts

Case Report: Introduction: Nephrogenic Diabetes Insipidis (DI) is a condition that interrupts patient’s ability to concentrate their urine and consequently they live in constant danger of dehydration that can lead to impaired mental status or death. We report a case of a patient with congenital nephrogenic DI developing severe hypernatremia leading to rhabdomyolosis, hyperkalemia and acute kidney injury.
Case Report: A 20 year-old incarcerated male presented with a complaint of lower extremity muscle cramps and generalized weakness for three days. The patient denied any recent trauma, exertion or exposure to extreme climate. He reported excessive thirst and urination since childhood, consistent with his diagnosis of DI that was ultimately confirmed by family. Other than clinical signs of severe dehydration, physical exam was normal, including a normal neurological exam. Initial laboratory data revealed serum sodium 202 mmol/L, potassium 2.4 mmol/L, Chloride >150 mmol/L, CO2 24 mmol/L, BUN 37 mg/dL, creatinine 1.7 mg/dL. The patient underwent aggressive volume replacement with normal saline, followed by large amounts of maintenance fluids, including ½ normal saline and D5 with bicarbonate. The patient was also started on amiloride and hydrochlorothiazide. After three days the patient’s sodium decreased to 167 mmol/L; however, his creatinine phospokinase levels reached 500,000 U/L, with potassium 7.7 mmol/L, creatinine 3.5 mg/dL and hemodyalysis was initiated.
Discussion: A dramatic alteration of body water homeostasis can be observed in individuals with diabetes insipidus. However, such severe hypernatremia in the absence of neurological deficits is unusual with only a few case reports with serum sodium >200. Diet modifications and medications can be employed to diminish the danger of dehydration and help control thirst, but when homeostasis cannot be maintained, patients are at risk for developing severe hypernatramia. The above patient had recently been incarcerated and had refused to drink the water provided, which lead to his disruption in homeostasis. Rhabdomyolysis and acute kidney injury are possible complications of severe hypernatremia, which were both evident in this case.