Kidney Week

Abstract: FR-PO0890

Potassium Under Siege: Voriconazole-Induced Rare Life-Threatening Hyperkalemia

Session Information

• Fluid, Electrolyte, and Acid-Base Disorders: Case Reports - 1
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Fluid, Electrolytes, and Acid-Base Disorders

• 1102 Fluid, Electrolyte, and Acid-Base Disorders: Clinical

Authors

• Makadia, Bhaktidevi, University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States

Bhaktidevi Makadia, MD

• Jaikaransingh, Vishal, University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States

Vishal Jaikaransingh, MBBS

• Mars, Ronald L., University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States

Ronald L. Mars, MD, FASN

• Hasan, Irtiza, University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States

Irtiza Hasan, MD, MS, MSc, FASN

Introduction

Voriconazole is a triazole antifungal commonly used for invasive aspergillosis & is associated with several recognized adverse effects, including hepatotoxicity, neurotoxicity, & acute kidney injury (AKI). Severe hyperkalemia related to voriconazole is rarely reported. We present a case of life-threatening refractory hyperkalemia requiring renal replacement therapy (RRT), suspected to be secondary to voriconazole-induced hypoaldosteronism.

Case Description

A 67-year-old male with tobacco use, insulin-dependent type 2 DM, CKD stage III (baseline creatinine 1.6–1.9 mg/dL), prior stroke without residual deficits, peripheral arterial disease, & chronic bilateral foot ulcers, presented with altered mental status. One week earlier, he had been discharged after prolonged hospitalization for septic shock & acute hypoxic respiratory failure secondary to cavitary pulmonary aspergillosis & was started on voriconazole.
On presentation, laboratory evaluation demonstrated mild AKI on CKD with creatinine 2.1 mg/dL & severe hyperkalemia with potassium 7.0 mEq/L. Hyperkalemia remained refractory despite aggressive medical management including sodium zirconium cyclosilicate & loop diuretics, ultimately requiring RRT. Further evaluation demonstrated aldosterone 1.2 ng/dL, plasma renin activity 0.47 ng/mL/hr, & aldosterone-renin ratio 2.5. Urine potassium was 13.7 mmol/L with fractional excretion of 11%, suggesting impaired renal potassium excretion. Voriconazole was discontinued on hospital day 3 due to concern for medication-related adverse effects contributing to AKI & hyperkalemia. Prior to voriconazole initiation, potassium was normal at 4.1 mmol/L & creatinine was at baseline. Following discontinuation, potassium remained normal without further need for RRT.

Discussion

Voriconazole-associated hyperkalemia is an uncommon but potentially life-threatening adverse effect. One proposed mechanism involves inhibition of adrenal steroidogenesis causing relative hypoaldosteronism, which impairs distal tubular potassium secretion & promotes potassium retention. Patients with underlying CKD, DM, or reduced renal reserve may be particularly susceptible. This case highlights the importance of recognizing unexplained refractory hyperkalemia in patients receiving voriconazole, particularly when accompanied by low renin & aldosterone levels. Early recognition & prompt discontinuation may prevent severe complications.