Unusual presentation of thyrotoxicosis as bradycardia, acute renal failure and hyperuricemia in an elderly patient.

Bradycardia with renal system involvement in patients with thyrotoxicosis has rarely been reported. We report a 72-year-old woman with unusual presentations of sinus bradycardia and normothermia accompanied by acute renal failure and hyperuricemia in thyrotoxicosis. The electrocardiogram changes in this patient included sinus bradycardia (50 beats per minute), followed by atrial fibrillation (84 beats per minute), and finally sinus rhythm with T wave inversion (80 beats per minute). Her renal function and hyperuricemia completely recovered after appropriate antithyroid therapy. A high index of suspicion is needed for early diagnosis and antithyroid treatment in patients with unusual manifestations of thyrotoxicosis in general clinical practice.