Renal tubular toxicity associated with tenofovir assessed using urine-beta 2 microglobulin, percentage of tubular reabsorption of phosphate and alkaline phosphatase levels.

Despite its wide use, the renal tubular toxicity of tenofovir has not been fully evaluated. Twelve weeks after initiating a tenofovir-containing HAART regimen, a high urine-beta 2 microglobulin level was observed in 12 out of 17 patients, the percentage of tubular reabsorption of phosphate decreased from 96.0 to 91.1% and alkaline phosphatase increased from 294 to 365 U/l, whereas serum creatinine and phosphorus remained largely unchanged. Patients with the above findings should be monitored carefully for renal tubular toxicity.