Acute renal failure due to amiodarone-induced hypothyroidism

Renal alterations in hypothyroidism include decreased glomerular filtration rate and renal plasma flow. We herein report a case of amiodarone -induced hypothyroidism associated with a rapid decrease of renal function, reversible upon amiodarone withdrawal. A 72-year-old man presented to our clinic in August 2007 reporting a recent deterioration of renal function. Ten weeks before he was admitted to another hospital for a supraventricular tachyarrhythmia treated with carvedilol 12.5 mg/day and amiodarone 400 mg/day. On admission, laboratory tests revealed altered renal function (serum creatinine 6 mg/dl, blood urea nitrogen 78 mg/dl) and severe hypothyroidism (free T4 0.27 pg/ml, free T3 1.49 pg/ml, TSH 183.36 mU/l). Amiodarone and carvedilol were stopped, while levothyroxine 75 mcg/die was started. After three months renal function had completely recovered to 1.9 mg/dl, BUN 28 mg/dl, with concurrent improvement of thyroid function free T4 14.2 pg/ml, free T3 6.4 pg/ml, TSH 15.5 mU/l.