Single zoledronic acid infusion as a cause of acute kidney impairment requiring dialysis in two patients with osteoporosis

Zoledronic acid is a widely used bisphosphonate for treating osteoporosis and hypercalcemia related to malignancy. It is also used to prevent bone loss induced by cancer treatment and bone metastases in various cancer types. Zoledronic acid is safe for most patients and is generally not associated with severe side effects. However, there have been reports of acute kidney impairment occurring after administration of intravenous zoledronic acid, mostly in patients with cancer (who received a high cumulative dose of this medication) or preexisting kidney impairment, and in patients with a history of nephrotoxic treatment. We report herein the cases of two patients without history of cancer, who developed dialysis-requiring acute kidney impairment after a single administration of intravenous zoledronic acid. None of the patients had previously used nephrotoxic medications, and one of them had a normal kidney function before zoledronic acid treatment. To the best of our knowledge, this report describes the first case of acute kidney impairment in a patient without risk factors. The findings of this report show that acute kidney impairment following intravenous zoledronic acid treatment can also occur in low-risk patients, highlighting the need for monitoring kidney function in all patients receiving this treatment.