Tenofovir Nephrotoxicity Mechanisms and Management

Clinical Manifestations

• Patients with tenofovir-induced nephrotoxicity may exhibit proximal tubular dysfunction, manifesting as Fanconi syndrome with normoglycemic glycosuria, hypophosphatemia, proteinuria, and metabolic acidosis due to bicarbonate wasting 1, 2, 3
• The American College of Physicians and other medical societies recommend monitoring for signs of tubulopathy, including glycosuria, phosphaturia, and proteinuria, in patients receiving tenofovir therapy 1

Risk Factors and Monitoring

• Concurrent medications that increase tenofovir levels, such as ritonavir-boosted protease inhibitors, can increase the risk of nephrotoxicity 1
• Regular monitoring of renal function is essential, especially in high-risk patients, with twice-yearly monitoring recommended for patients on tenofovir plus ritonavir or cobicistat 1, 4

Management

• The National Kidney Foundation and other medical societies recommend discontinuing tenofovir immediately upon diagnosis of Fanconi syndrome or significant renal dysfunction, and considering alternative antiretrovirals such as tenofovir alafenamide (TAF) or abacavir 1, 3

Tenofovir Nephrotoxicity Prevention and Management

Prevention Strategies

• The Infectious Diseases Society of America recommends avoiding tenofovir in patients with pre-existing kidney disease when alternatives exist, and reducing tenofovir dose based on estimated creatinine clearance in patients with renal impairment, to minimize the risk of nephrotoxicity 5
• The guideline suggests avoiding concurrent use of other potentially nephrotoxic drugs, especially ritonavir-boosted protease inhibitors, to reduce the risk of tenofovir-induced nephrotoxicity 5