A 39-year-old man with resistant hypertension,presented with headache and dizziness at the emergency department on January 6,2012.The patient had a history of hypertension for 3 years,his highest blood pressure was 250/110 mmHg,and he was taking antihypertensive medication regimens for at least 6 months.A mitral replacement by bioprosthetic valve had been implanted 6 months before.The patient was in chronic renal failure (CRF) uremia,maintenance of which he underwent the standard hemodialysis treatment three times a week for 6 months.Hemodialysis was done using anti-seepage,bicarbonate dialysate,the German Fresenius 4008S dialysis machine,with a blood flow of an average of 240 ml/min,dialysis flow 500 ml/min,4 hours/time.Coronary artery disease,secondary hypertension,and type 2 diabetes mellitus were excluded.After admission,this patient was subjected to ambulatory blood pressure monitoring and adrenal computed tomography.Estimated glomerular filtration rate (eGFR) was calculated by simple modification of diet in renal disease (MDRD) equation for Chinese.1 All blood samples were taken a day before dialysis in order to exclude interference.