Incidence of renal toxicity in HIV-infected, antiretroviral-naive patients starting tenofovir/emtricitabine associated with efavirenz, atazanavir/ritonavir, or lopinavir/ritonavir

Objectives: We performed a retrospective cohort study of HIV-infected antiretroviral-naive patients starting a first antiretroviral therapy with tenofovir/emtricitabine plus efavirenz (EFV), atazanavir/ritonavir (ATV/r), or lopinavir/ritonavir (LPV/r). Methods: The incidence of renal impairment or proximal tubular dysfunction was evaluated during a 12-month follow-up. Renal impairment was diagnosed by a reduced estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease (MDRD) formula, and tubular dysfunction was diagnosed when >= 2 among proteinuria, glucosuria, hypouricaemia, hypophosphataemia, and hypokalaemia, were identified. Results: A total of 235 patients were enrolled: 82 taking EFV, 78 ATV/r, and 75 LPV/r. The mean decline in eGFR after the 12-month follow-up was significantly greater in subjects treated with ATV/r (-10.4 ml/min/1.73 m(2)) than in those receiving EFV (-5.1; p = 0.002) or LPV/r (-4.8; p = 0.003). Similarly, a significantly higher incidence of proximal tubulopathy was observed among ATV/r-treated patients (14.1%) compared with patients receiving EFV (4.9%) or LPV/r (5.3%). Conclusions: In our retrospective study, naive patients receiving tenofovir/emtricitabine and ATV/r for 12 months showed a significantly higher decline in eGFR and a significantly higher incidence of proximal tubulopathy than those receiving tenofovir/emtricitabine plus EFV or LPV/r, even though clinically evident renal toxicity associated with tenofovir-based treatment is a very uncommon event.