Challenges in diagnosing and treating a patient with renal artery fibromuscular dysplasia: case report

Abstract

Background We present a patient with history of sinus venous thrombosis and hypertension during the last year. Her blood pressure was not controlled d espite drugs, diet, and exercise. She denied symptoms. She does not smoke nor drink alcohol. Her body mass index was 20 kg/m 2 , NYHA Class I/IV. Case summary A 40-year-old Latin-American female patient, concerned because despite taking verapamil 160 mg/day, losartan 100 mg/day, and hydrochlorothiazide 25 mg/day her diastolic blood pressure was over 100 mmHg. Routine serum and urine lab tests and a transthoracic echocardiogram were done and were normal. The treatment was increased over the next consultations but without control of her blood pressure. She developed resistant hypertension, and she was taking four antihypertensive drugs and two diuretics. A first renal artery Doppler was normal. Because of a high clinical suspicion a renal angio-CT was performed showing bilateral fibromuscular dysplasia. The patient underwent a renal artery angioplasty with balloon with excellent results and better control of her blood pressure after the procedure. Over the next month, her doctors were able to decrease her treatment to two drugs at intermediate doses. Currently, she is doing well and asymptomatic. Discussion Renal artery fibromuscular dysplasia (FMD) could be a challenging disease to be diagnosed. Patients with this condition may suffer from symptomatic and resistant hypertension. Many patients do not have abnormalities on their physical exam or in the routine lab tests. Treatment includes renal artery angioplasty if patient is symptomatic and blood pressure is resistant.

Renal Artery Stenosis: Diagnostic and Management Problems

“…[1,5,9] Figure 1. Pathophysiology of renal artery stenosis [7] In an experimental study, significant hemodynamic changes that causes hypertension occurred in 75-80% of lumen occlusion. But critical point for lumen occlusion in human still could not be determined.…”

“…Persistent RAAS activation occurred in stenotic kidney, but not in contralateral kidney. [7] Fibromuscular dysplasia (FMD) is often found in pre-menopausal women with age between 15-50 years old and it closely related to history of hypertension and smoking. FMD patients generally had good clinical condition with low cardiovascular risk.…”

“…[9] Beside ACE inhibitor, other anti-hypertension which could be recommended is angiotensin receptor blocker (ARB). [7] When there is failure of conservative therapy in which the blood pressure did not come down, and accompanied by recurrent flash pulmonary edema, worsened azotemia, with evidence of significant renal artery stenosis, patient could be considered to be sent for revascularization. Revascularization should also consider about patient's age and pulse pressure.…”

“…Some studies observed inflammation reducing therapy may offer some benefit for some patients with chronic renal failure with renal artery stenosis. [7] Best result of revascularization was obtained in non-atherosclerotic FMD in which stenosis correction often improve blood pressure control and renal function. ASTRAL study revealed angioplasty and stenting may give some benefit for atherosclerotic renal artery stenosis but the evidence was still scarce regarding improvement of blood pressure control and renal function.…”

“…[5,6] Recently, studies indicated renal artery revascularization did not improve patients' outcomes in the aspects of renal function and cardiovascular outcomes. [7] Angioplasty and stenting procedures offered excellent results for fibromuscular dysplasia, but evidence was not enough to prove benefit for blood pressure control and renal function improvement. Both procedures also possessed high prevalent risks and did not provide any prevention from cardiovascular risk.…”