Reversibility of pamidronate-associated glomerulosclerosis.

Bisphosphonates such as pamidronate are widely used in the treatment of patients with lytic bony lesions secondary to breast cancer or multiple myeloma, yet they have been associated with deterioration of renal function and histopathological changes in the kidney. There have been recent reports associating the use of pamidronate with the development of the collapsing variant of focal segmental glomerulosclerosis (CFSGS), a rapidly progressive variant of focal segmental glomerulosclerosis that leads to end-stage renal disease. We describe five patients who developed worsening renal function, proteinuria, and nephrotic syndrome while taking pamidronate; three of them had biopsy-proven CFSGS.