MKSAP Quiz: Follow-up for stable chronic kidney disease
A 57-year-old man is evaluated during follow-up for stable chronic kidney disease diagnosed 1 year ago. He also has type 2 diabetes mellitus, hyperlipidemia, and peripheral artery disease. On physical examination, blood pressure is 128/74 mm Hg, pulse rate is 65/min, and respiration rate is 18/min. Bilateral carotid and lower abdominal quadrant bruits are heard. Peripheral extremity pulses are diminished. The remainder of the examination is normal. After laboratory studies, what is the appropriate management?
A 57-year-old man is evaluated during a follow-up visit for stable chronic kidney disease diagnosed 1 year ago. Renal duplex Doppler ultrasound at that time showed a 7-cm right kidney and 11-cm left kidney with a >75% midstenotic lesion of the left renal artery. He also has type 2 diabetes mellitus, hyperlipidemia, and peripheral artery disease. Medications are low-dose aspirin, furosemide, lisinopril, amlodipine, carvedilol, metformin, empagliflozin, and atorvastatin.
On physical examination, blood pressure is 128/74 mm Hg, pulse rate is 65/min, and respiration rate is 18/min. Bilateral carotid and lower abdominal quadrant bruits are heard. Peripheral extremity pulses are diminished. The remainder of the examination is normal.
Laboratory studies:
| Creatinine | 1.4 mg/dL (123.8 µmol/L) |
| Electrolytes | Normal |
| Estimated glomerular filtration rate | 45 mL/min/1.73 m2 |
| Urine albumin-creatinine ratio | 1100 mg/g |
Which of the following is the most appropriate management?
A. Left renal artery angioplasty
B. Renal artery CT angiography
C. Renal artery MR angiography
D. No additional diagnostic testing
MKSAP Answer and Critique
The correct answer is D. No additional diagnostic testing. This content is available to MKSAP 19 subscribers as Question 18 in the Nephrology section. More information about MKSAP is available online.
No additional diagnostic testing (Option D) is needed for this patient with stable renovascular hypertension. Clinical suspicion for renovascular hypertension is raised when patients >55 years of age present with onset of severe hypertension and develop acute kidney injury (AKI) after initiation of an ACE inhibitor or angiotensin receptor blocker (ARB), or after control of blood pressure (BP) to target goal. In addition, asymmetry >1.5 cm in kidney sizes on imaging or the presence of a kidney ≤9 cm can also increase the probability. Patients such as this one with evidence of atherosclerotic cardiovascular disease should receive medical therapy, including lifestyle interventions, low-dose aspirin, BP control, guideline-directed diabetes management, and high-intensity statin therapy. In patients with hypertension and chronic kidney disease (CKD) stage G3 or higher or stage G1 or G2 with albuminuria, treatment with an ACE inhibitor or ARB is recommended to slow kidney disease progression.
Three randomized trials (STAR, ASTRAL, and CORAL) failed to show that renal artery angioplasty (Option A) confers additional benefit above optimal medical therapy in patients with renovascular hypertension and stable kidney function. Patients who may benefit from percutaneous angioplasty or surgical intervention include those with a short duration of hypertension; atherosclerotic renovascular disease refractory to optimal medical therapy; severe hypertension or recurrent acute flash pulmonary edema; AKI following treatment with an ACE inhibitor or ARB; progressive impaired kidney function believed to be caused by bilateral renovascular disease; or unilateral stenosis affecting a solitary functioning kidney. This patient has none of these indications. Finally, patients with advanced CKD or with proteinuria >1000 mg/g, such as this patient, are less likely to benefit from revascularization.
Although CT angiography and MR angiography (Options B, C) have higher diagnostic utility than ultrasonography, these imaging studies may be potentially harmful in patients with severe CKD, given the risk for contrast nephropathy and gadolinium-induced nephrogenic systemic fibrosis (with group 1 but not group 2 gadolinium-based contras media). Renal duplex Doppler ultrasonography is a reasonable imaging modality in these patients if performed by experienced sonographers. Additional testing for renal vascular disease is not required in this patient and is not cost-effective, given that no interventions other than continuing the current medical management will be undertaken.
Key Point
- In most patients with renal artery stenosis, the primary therapeutic intervention is medical management, including correction of modifiable cardiovascular risk factors.