Acute Kidney Injury Associated with ACE Inhibitors

Introduction to ACE Inhibitor-Induced AKI

ACE inhibitors can contribute to acute kidney injury (AKI) by altering renal hemodynamics, particularly in scenarios such as volume depletion, concurrent nephrotoxin use, or pre-existing kidney disease 1

Elevations in serum creatinine up to 30% from baseline with ACE inhibitors may not indicate true AKI and could be associated with long-term kidney protection, as demonstrated by the ACCORD BP trial 1
The American College of Cardiology (ACC) recommends considering these elevations in the context of long-term kidney protection 1

Regular assessment of renal function and potassium levels, especially after initiation or dose changes of ACE inhibitors, is recommended 2
Monitoring kidney function within 1-2 weeks after initiating or increasing doses of ACE inhibitors can minimize AKI risk 2
The American Heart Association recommends temporary discontinuation of RAAS inhibitors in patients with AKI until renal function has returned to baseline or stabilized, particularly in conditions like bilateral renal artery stenosis or stenosis in a solitary kidney 3
After AKI resolution, it is recommended to wait until renal function has stabilized, ensure adequate volume status and blood pressure, consider starting at a lower dose than previously used, and monitor renal function and potassium within 2-4 weeks after restarting 4, 5

The combination of ACE inhibitors and ARBs increases AKI risk and is contraindicated, according to the American Heart Association (AHA) guidelines 2
The Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines recommend implementing "sick day protocols" which include holding SGLT2 inhibitors during acute illness, particularly with volume depletion 4
SGLT2 inhibitors can cause an initial "eGFR dip" of 3-5 mL/min/1.73 m² within the first 4 weeks of therapy, which is usually reversible and part of their normal mechanism of action 4
The American College of Cardiology notes that SGLT2 inhibitors have diuretic and natriuretic effects that could worsen volume depletion in AKI 6

For creatinine clearance >30 mL/min, standard dosing of ACE inhibitors/ARBs is recommended, with consideration of the American College of Cardiology's guidelines 7
The American College of Cardiology recommends reduced initial dose by 50% for creatinine clearance 10-30 mL/min, and starting at 25% of normal dose for creatinine clearance <10 mL/min or hemodialysis, with a strength of evidence supported by 7
Target or above-target dosages of ACEi/ARBs are associated with a higher risk of AKI compared to lower doses, according to the Kidney International guidelines 8

ACE inhibitors/ARBs provide significant benefits in diabetic nephropathy, including delaying progression of nephropathy in type 1 and 2 diabetes, as reported by 9, 10
The Kidney International guidelines advise against using ACEi and ARB combinations due to increased risk of AKI and hyperkalemia, and recommend considering GI cation exchangers (potassium binders) in patients with hyperkalemia on RAAS inhibitors 5

Regular assessment of renal function and potassium levels, vigilant monitoring when restarting RAAS inhibitors after AKI resolution, avoiding concurrent nephrotoxic medications, and reassessing medication regimen as renal function changes are crucial for optimal patient outcomes, with consideration of the American Heart Association's guidelines 3, 7, 11
Nephrotoxic medications, including NSAIDs, should be strictly avoided, with medication decisions guided by current renal function and trajectory, considering the mode of excretion, potential for nephrotoxicity, effect of AKI on drug metabolites, urgency of use, and availability of suitable alternatives, as reported by 11