Case Report: Voriconazole induced refractory hyperkalemia and adrenal insufficiency

Voriconazole, an azole drug, inhibits cytochrome P450 dependent lanosterol 14-alpha-demethylase. It is a potent anti-fungal agent. Adverse effects include neurotoxicity, cardiac arrhythmias, electrolyte disturbances and adrenal insufficiency. Hyperkalemia is a rare adverse effect that has been described, but is not well reported, in the literature. We present a case of intractable hyperkalemia resulting from voriconazole use. A 47-year-old male presented with worsening shortness of breath, requiring mechanical ventilation within 24 hours of presentation. Diagnosis of acute respiratory distress syndrome was made. Empirical treatment with broad-spectrum antibacterial coverage resulted in no improvement. Voriconazole was added for anti-fungal coverage, causing treatment resistant hyperkalemia necessitating continuous renal replacement therapy (CRRT). Renal function remained normal. Stopping voriconazole restored normal potassium levels. CRRT was discontinued. Hyperkalemia caused by voriconazole occurs in less than 2% of cases. It is a potentially life-threatening side effect. Physicians should be aware of this association and seek alternative treatment when necessary.