LETTERS AND COMMENTS wk history of polyuria and polydipsia. Past medical history was positive for hypertension and negative for diabetes mellitus, neurologic, thyroid, or liver disease. Medications included a thiazide diuretic and alpha-methyldopa. Physical examination revealed an alert, oriented woman in no acute distress. Pulse was 72 beats/min and blood pressure was 136/ 88 mm Hg. The patient exhibited choreoathetotic movements of the right face, tongue, arm, and leg, and increased tone in the right upper and lower extremities. The serum glucose concentration was 584 mg/dl. Serum electrolytes, blood urea nitrogen, creatinine, calcium, phosphate, thyroid, and liver function tests were within normal limits. A CT scan of the brain revealed bilateral, 1-mm calcification of the caudate nuclei. The EEG was within normal limits. The choreoathetotic movements abated with return of the serum glucose to the 200-300-mg/dl range with insulin and hydration. The patient was discharged on haloperidol, intermediateacting insulin, and the same antihypertensive regimen.Haloperidol was subsequently discontinued due to excessive sedation.The patient did well for -1 yr without any abnormal movements and serum glucose concentrations between 150 and 275 mg/dl when she presented with a 2-wk history of polyuria and a 3-day history of involuntary movements of the left face, tongue, arm, and leg, but no abnormal movements of the right side. The remainder of the examination was unchanged. The serum glucose level was 622 mg/dl. Serum electrolytes, calcium, phosphate, thyroid, and parathyroid hormone levels were within normal limits. CT scan of the brain revealed increasing calcification of the posterior head of the caudate nuclei bilaterally. EEG was again within normal limits. The choreoathetotic movements abated after the serum glucose level was normalized with insulin. The patient was discharged on intermediate-acting insulin and has had no further abnormal movements with continued good control of hyperglycemia.
DISCUSSIONAcquired paroxysmal choreoathetotic movement disorders arise from hypoparathyroidism, hyperthyroidism, and several neurologic diseases. 2 ' 3 A review of the etiologies of acquired paroxysmal choreoathetosis revealed that 60% of the cases are unilateral, 30% are bilateral, and the remaining 10% are alternately unilateral and bilateral. 2 Our case demonstrates that choreoathetotic movements associated with diabetes mellitus may be alternately unilateral during periods of hyperglycemia and be successfully managed by restoring normoglycemia with insulin. Insulin therapy and hydration have been shown to be effective therapies for other neurologic manifestations of hyperglycemia and hyperosmolarity, including focal seizures and transient ischemic attacks, 4 by reestablishing previous osmotic gradients.The choreoathetotic movements and basal ganglia calcification reported in this case are also seen in idiopathic hypoparathyroidism, a rare disorder in which neurons in the basal ganglia damaged by anoxia or vascular insuffici...
