What is the management plan for a patient with persistent proteinuria and an elevated microalbumin-to-creatinine (Microalb/creat) ratio, who has been started on low-dose lisinopril (Zestril) (angiotensin-converting enzyme inhibitor) for renal protection?

From the Guidelines

For persistent proteinuria with an elevated microalbumin/creatinine ratio of 87, starting lisinopril 5 mg daily is an appropriate initial treatment approach, but the dose should be uptitrated to a maximally tolerated or allowed daily dose as first-line therapy, as recommended by the KDIGO 2021 clinical practice guideline for the management of glomerular diseases 1. This ACE inhibitor helps protect kidney function by reducing pressure within the kidneys and decreasing protein leakage. The medication should be taken consistently, and follow-up testing of kidney function and proteinuria is recommended to assess treatment effectiveness. Patients should monitor their blood pressure regularly while taking this medication, as lisinopril can lower blood pressure. Common side effects include dry cough, dizziness, and rarely angioedema. Potassium levels should be monitored as ACE inhibitors can cause hyperkalemia. Patients should avoid NSAIDs when possible as they can reduce the kidney-protective effects of lisinopril. This treatment addresses the underlying pathophysiology by blocking the renin-angiotensin-aldosterone system, which reduces intraglomerular pressure and proteinuria, ultimately slowing progression of kidney damage, as supported by the executive summary of the KDIGO 2021 guideline for the management of glomerular diseases 1. Additionally, the use of ACEi or ARB to maximally tolerated or allowed dose as first-line therapy in treating patients with both hypertension and proteinuria is recommended, as stated in the KDIGO 2021 clinical practice guideline for the management of glomerular diseases 1. It is also important to note that the benefits and safety of ACEi or ARB are uncertain in patients with diabetes or cardiovascular disease, and combinations of ACEi and ARB may be used in young adults without caveat, as mentioned in the KDIGO 2021 clinical practice guideline for the management of glomerular diseases 1. However, the most recent and highest quality study, the KDIGO 2021 clinical practice guideline for the management of glomerular diseases 1, should be prioritized in making treatment decisions. Key considerations in the management of patients with persistent proteinuria include:

• Uptitrating the dose of lisinopril to a maximally tolerated or allowed daily dose
• Monitoring blood pressure and potassium levels regularly
• Avoiding NSAIDs when possible
• Following up on kidney function and proteinuria to assess treatment effectiveness
• Considering the use of ACEi or ARB in combination with other medications, such as diuretics, to achieve optimal blood pressure control and reduce proteinuria, as recommended by the executive summary of the KDIGO 2021 guideline for the management of glomerular diseases 1.

From the FDA Drug Label

Monitor renal function periodically in patients treated with lisinopril. Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system. Patients whose renal function may depend in part on the activity of the renin-angiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe congestive heart failure, post-myocardial infarction or volume depletion) may be at particular risk of developing acute renal failure on lisinopril.

The patient has persistent proteinuria and is starting low-dose lisinopril for kidney protection. The key points to consider are:

• Monitoring renal function is necessary while on lisinopril.
• Patients with chronic kidney disease may be at risk of developing acute renal failure on lisinopril. The decision to start lisinopril for kidney protection in a patient with persistent proteinuria should be made with caution, and renal function should be monitored periodically 2.

From the Research

Lisinopril for Kidney Protection

• The patient has been prescribed low-dose lisinopril 5 mg p.o. for kidney protection due to persistent proteinuria, as indicated by a Microalb/creat ratio of 87(H) 3.
• Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor that has been shown to be effective in reducing proteinuria and providing kidney protection 4.
• The reduction of proteinuria by lisinopril is not only due to its blood pressure lowering effect, but also due to its ability to reduce intraglomerular capillary pressure and overall renal vascular resistance 4.

Dosage and Administration

• The prescribed dosage of 5 mg p.o. is a low dose, which is recommended for patients with kidney disease or those at risk for renal artery stenosis 3.
• It is essential to monitor the patient's blood pressure and renal function while on lisinopril therapy, especially when initiating treatment or adjusting the dosage 5.
• Once daily administration of lisinopril is recommended for compliance reasons 3.

Side Effects and Interactions

• The patient has been educated on the potential side effects of lisinopril, which are generally well-tolerated, with few serious adverse effects reported 6, 7.
• However, patients with renal insufficiency or those taking diuretics may be at risk for hyperkalemia, and therefore, require close monitoring 3.
• The combination of lisinopril with other medications, such as angiotensin II receptor blockers (ARBs), may increase the risk of acute renal failure, emphasizing the need for careful surveillance of renal function and blood pressure 5.