Test your medicine knowledge with the MKSAP challenge, in partnership with the American College of Physicians.

A 65-year-old man is evaluated during a follow-up visit for stage G3b/A3 chronic kidney disease due to diabetic nephropathy. He reports doing well with good baseline exercise tolerance and no shortness of breath. Medical history is also significant for type 2 diabetes mellitus and hypertension. Medications are basal bolus insulin and lisinopril, 20 mg/d.

On physical examination, temperature is normal, blood pressure is 145/75 mm Hg, pulse rate is 82/min, and respiration rate is 16/min. BMI is 28. There is no jugular venous distention. The lungs are clear.

Laboratory studies:

Bicarbonate	Normal
Creatinine	1.9 mg/dL (168 µmol/L)
Potassium	4.0 mEq/L (4.0 mmol/L)
Estimated glomerular filtration rate	42 mL/min/1.73 m2
Urine protein-creatinine ratio	3900 mg/g

Kidney ultrasound shows mildly echogenic kidneys that are of normal size with no obstruction.

Which of the following is the most appropriate treatment?

A. Add an angiotensin receptor blocker
B. Increase lisinopril dose
C. Replace lisinopril with amlodipine
D. No change in current medications

MKSAP Answer and Critique

The correct answer is B. Increase lisinopril dose.

The most appropriate treatment for this patient is to increase the dose of the ACE inhibitor lisinopril. He has chronic kidney disease (CKD) with nephrotic-range proteinuria (urine protein-creatinine ratio >3500 mg/g or a urine protein excretion >3500 mg/24 h) and inadequately controlled hypertension. Increasing lisinopril should decrease his blood pressure and result in some decrease in proteinuria. Although many clinicians are hesitant to escalate the dose of an ACE inhibitor or angiotensin receptor blocker (ARB) in patients with significant CKD, careful upward titration is generally well tolerated with close clinical follow-up. The eighth report from the Joint National Committee (JNC 8) recommends lowering blood pressure to <140/90 mm Hg, although some experts recommend a lower blood pressure goal of <130/80 mm Hg in patients with heavy proteinuria.

Recent studies have demonstrated that although adding an ARB to an ACE inhibitor usually decreases proteinuria, combination therapy does not improve clinical outcomes and increases the risk of acute kidney injury and hyperkalemia.

Most patients with CKD, and those with CKD and proteinuria in particular, should be treated with an ACE inhibitor or ARB as preferred initial medications due to their demonstrated ability to slow CKD progression. Therefore, replacing lisinopril with the calcium channel blocker amlodipine is not appropriate in this case.

Continuing this patient’s current therapy would not improve blood pressure control or decrease proteinuria.

Key Point

• Blood pressure control using an ACE inhibitor or angiotensin receptor blocker is the therapy of choice in patients with chronic kidney disease.

This content is excerpted from MKSAP 17 with permission from the American College of Physicians (ACP). Use is restricted in the same manner as that defined in the MKSAP 16 Digital license agreement. This material should never be used as a substitute for clinical judgment and does not represent an official position of ACP. All content is licensed to KevinMD.com on an “AS IS” basis without any warranty of any nature. The publisher, ACP, shall not be liable for any damage or loss of any kind arising out of or resulting from use of content, regardless of whether such liability is based in tort, contract or otherwise.