Question

A 50-year-old female with uncontrolled hypertension on three drugs presents with giddiness and a bruit. The bruit is heard in both systolic and diastolic phases. The patient also has anuria. Which of the following is true?

• A. Renal revascularisation after non-contrast MR angiogram
• B. Emergency surgery for impending aortic rupture
• C. Conservative management with increasing dose and no role for surgery
• D. Patient needs anti-impulse therapy and no role for further imaging

Hint:

A continuous (systolic-diastolic) abdominal bruit in a hypertensive patient is highly specific for Renal Artery Stenosis. Always avoid contrast-enhanced CT or standard gadolinium MRI in patients with anuria or severe renal failure (eGFR $<$ 30 mL/min).

Answer 1

The Correct Option is A

Concept:
The clinical presentation of resistant hypertension, a continuous systolic-diastolic abdominal bruit, and acute anuria is the classic triad of critical Renovascular Hypertension complicated by acute ischemic renal failure.
Explanation:
• The presence of a bruit that extends through both systole and diastole is highly specific for a hemodynamically significant stenosis, most commonly involving the renal arteries in this clinical context.

• Resistant hypertension (uncontrolled despite the use of three antihypertensive agents) strongly points to a secondary cause, with Renal Artery Stenosis (RAS) being the most common curable etiology.

• The sudden onset of anuria indicates that the remaining functional renal parenchyma is critically underperfused, possibly due to bilateral RAS, stenosis in a solitary functioning kidney, or an acute thrombotic occlusion superimposed on a chronic stenosis.

• Emergent imaging is required to define the vascular anatomy before intervention. However, the patient's anuric state (acute kidney injury) strictly contraindicates the use of iodinated contrast (due to contrast-induced nephropathy) and standard gadolinium contrast (due to the risk of nephrogenic systemic fibrosis).

• Therefore, a non-contrast imaging modality, such as a non-contrast Magnetic Resonance Angiogram (MRA) or duplex ultrasonography, is the safest and most appropriate diagnostic step.

• Once the stenosis is anatomically confirmed, urgent renal revascularisation (via endovascular stenting or surgical bypass) is imperative to salvage the kidney and restore urine output.
Final Answer:
The patient requires urgent renal revascularisation, which must be preceded by a non-contrast MR angiogram to safely evaluate the vascular anatomy without worsening renal injury.