Author:
Denewet K.,Dejaeger M.,Gielen E.
Abstract
Acute tubular necrosis following zoledronic acid for the treatment of osteoporosis: case report and literature review
Zoledronic acid is a potent intravenous bisphosphonate widely used in the treatment of osteoporosis, amongst others. Bisphosphonate nephrotoxicity has been described for a long time, is dose-dependent and is more common when used in oncologic indications.
A case of acute tubular necrosis following a treatment with zoledronate in a patient with osteoporosis is described. An 88-year-old male patient was admitted with general weakness and recurrent falls, 10 days after the fourth, annual administration of 5 mg of zoledronic acid. Acute on chronic kidney injury with a creatinine of 6.77 mg/dL compared to the baseline of 1.7 mg/dL was established. There was a temporary requirement for dialysis because of metabolic complications. The diagnosis of toxic acute tubular necrosis was made. After 6 weeks, there was a gradual improvement to a creatinine of 2.64 mg/dL.
The case description is followed by a description of the mechanisms of nephrotoxicity of zoledronic acid and by a literature overview about its prevention in osteoporosis. Measurement of the serum creatinine before the infusion of zoledronic acid, awareness of possible nephrotoxicity and preventive measures are important to prevent acute kidney failure in patients with osteoporosis treated with zoledronic acid. Given the clearly proven effect of zoledronic acid on the fracture risk, the very low risk of renal side effects is certainly not a reason to avoid zoledronic acid in patients with a creatinine clearance above 35 ml/min according to the Cockcroft-Gault equation (CG).