Tenofovir induced acute kidney injury and its outcome; an Indian perspective

Introduction: Tenofovir remains the cornerstone drug in various antiretroviral regimens and is commonly associated with renal failure in susceptible individuals with a renal biopsy suggestive of proximal tubular injury. Objectives: To investigate clinical, histopathological and outcome findings in tenofovir-induced nephrotoxicity patients. Patients and Methods: Between August 1, 2014, and March 31, 2017, an observational study was conducted in a government-run tertiary care facility in South India. All patients receiving a regimen based on tenofovir disoproxil fumarate (TDF) and testing positive for human immunodeficiency virus (HIV) were included. A renal biopsy was performed when needed. Results: A total of 27 cases were identified, with a mean age of 45.03± 12.95 years, while 19 (70%) of them were men. Mean creatinine and mean proteinuria among the participants were 5.78 ±2.71 mg/dL and 1643.96 ±1056.44 mg/dL, respectively, at the time of the renal biopsy. Interval between TDF treatments to kidney biopsies ranged between 7 to 52 weeks with mean (±SD) of 30.8±22 weeks. Phosphaturia and glycosuria were found in 10 (37.03%) and 8 (29.5%) patients respectively, all of whom had normoglycemia. In contrast to the remaining 13 instances, which all had moderate to severe diffuse inflammation, 14 patients exhibited toxic proximal tubular damage along with mild and localized interstitial inflammation. Hemodialysis was required by 10 individuals. A total of 22 patients were monitored after TDF was stopped, while 17 (77.27%) of them had fully recovered renal function at the end of monitoring period. Conclusion: This study demonstrates that TDF nephrotoxicity is a reversible form of toxic acute tubular necrosis with concurrent interstitial inflammation that affects the proximal tubules. As a result, it is crucial to carefully monitor renal parameters in these patients.