SEIZURES: II

Abstract

A 55‐year‐old African‐American hemodialysis patient presented to the emergency room with complaints of nausea and vomiting. The patient had been on hemodialysis for two years secondary to diabetic nephropathy. Her baseline blood pressure was approximately 120/70 mm Hg on no antihypertensive medications. Five months previously, she was started on erythropoietin, 2000 units subcutaneously twice weekly, at which time her hematocrit was 23%. Her erythropoietin dose was gradually increased to 3500 units subcutaneously thrice weekly two months prior to admission. With this dosage, her hematocrit increased to 31%. Several weeks prior to admission, the patient's calcium carbonate was increased to correct a rising serum phosphate. In the emergency room her physical examination was remarkable for a blood pressure of 196/94 mm Hg. Funduscopic examination showed changes consistent with diabetic retinopathy but no evidence of papilledema or hemorrhages. Neurologic examination was nonfocal. An electrolyte panel revealed a serum sodium of 139 mEq/1, potassium 4.8 mEq/l, chloride 98 mEq/l, total CO2 29 mEq/l, blood urea nitrogen (BUN) 50 mg/dl, creatinine 11.4 mg/dl, glucose 125 mg/dl, calcium 13.6 mg/dl, phosphate 5.7 mg/dl, and albumin 4.2 mg/dl. While in the emergency room, the patient sustained a generalized tonic‐clonic seizure. Seizure activity ceased with the administration of diazepam 5 mg intravenously. Electrolytes were repeated immediately after the seizure, with sodium 137 mEq/l, potassium 4.6 mEq/l, chloride 98 mEq/l, and total CO2 17 mEq/l. Three hours later, electrolytes were again repeated, showing a sodium of 133 mEq/l, potassium 6.0 mEq/l, chloride 100 mEq/l, and total CO2 26 mEq/l. She was admitted for further evaluation. Phenytoin was begun at 100 mg po tid, and the patient had no further seizures. Without intervention, her blood pressure decreased to 114/70, which was stable over the next several days. Head computerized axial tomographic (CAT) scan, lumbar puncture, and electroencephalogram (EEG) were all unremarkable. The intact PTH level returned at less than 15 pg/ml, and the aluminum level was 14 mcg/ml. Hypercalcemia was treated with intravenous etidronate followed by adjusting the patient's calcium carbonate regimen. Over the next several months, phenytoin was withdrawn, and erythropoietin reintroduced. The patient has remained seizure‐free and normocalcemic over the following twelve months.