Incomplete Reversibility of Tenofovir-Related Renal Toxicity in HIV-Infected Men

Background: Significant nephrotoxicity develops in 1%-2% of HIV-infected adults receiving tenofovir (TDF). This nephrotoxicity is said to resolve rapidly, but this assessment is based on short follow-up, very few patients and use of serum creatinine, an insensitive measure of renal function. Methods: We determined the reversibility of TDF-related nephrotoxicity in 24 HIV-infected male outpatients who ceased TDF for renal impairment by retrospective assessment of estimated glomerular filtration rate (eGFR) using the Modified Diet in Renal Disease equation. Results: Median (interquartile range) eGFR pre-TDF was 74 (6188) mL.min(-1) . 1.73 m(-2), fell to 51 (39-61) mL.min(-1) . 1.73 m(-2) at TDF cessation and increased to 58 (48-70) mL.min(-1) . 1.73 m(-2) a median 13 months after TDF cessation (most recent vs pre-TDF eGFR; P = 0.0008). Results were similar with the Cockcroft-Gault equation and after exclusion of patients who had shorter follow-up after TDF cessation. Only 10 (42%) patients reached their pre-TDF eGFR. Greater eGFR improvement was significantly associated with more rapid decline in eGFR on TDF therapy and in those who received TDF with a protease inhibitor, with a trend for shorter duration of TDF therapy. Discussion: In this population, TDF-related renal toxicity was not always fully reversible.