Aliskiren-associated acute renal failure with hyperkalemia.

Area of Science:

• Nephrology
• Pharmacology
• Cardiology

Background:

• Aliskiren, a direct renin inhibitor, is a newer antihypertensive medication.
• Angiotensin II receptor antagonists like irbesartan are commonly used for hypertension.
• Spironolactone is a potassium-sparing diuretic often used with other antihypertensives.

Observation:

• A 76-year-old female patient switched from irbesartan to aliskiren for blood pressure control.
• Spironolactone was continued despite normal baseline renal function and electrolytes.
• The patient developed acute oliguric renal failure, hyperkalemia, and metabolic acidosis two weeks after starting aliskiren.

Findings:

• The patient required emergency dialysis due to severe hyperkalemia and renal failure.
• Undiagnosed chronic kidney disease (CKD Stage 2-3) was a significant predisposing factor.
• Continuation of spironolactone alongside aliskiren exacerbated the risk of hyperkalemia and renal impairment.

Implications:

• This case highlights a potential adverse drug reaction between aliskiren and spironolactone, particularly in patients with renal insufficiency.
• Careful patient selection and monitoring are crucial when initiating aliskiren, especially in those with pre-existing kidney disease or on potassium-sparing diuretics.
• Clinicians should be vigilant for acute kidney injury and hyperkalemia in patients treated with direct renin inhibitors and spironolactone concurrently.