A model for predicting nephrotoxicity in patients treated with aminoglycosides.

We have previously identified risk factors for nephrotoxicity in 204 patients receiving aminoglycosides. We added data on an additional 134 patients from the University of Chicago who were treated for longer periods (13.1 +/- 9.4 days) to determine if duration of therapy was also a risk factor. In the combined populations, nephrotoxicity developed in 59 (17.5%) of 338 patients, and duration of therapy was the factor most strongly associated with nephrotoxicity (P less than .0001). A new predictive model was developed that was then tested prospectively on 175 consecutive medical and surgical patients who had plasma levels of aminoglycoside measured. The new model accurately identified 14 of 15 patients with nephrotoxicity (sensitivity = 93%) and 106 of 160 without nephrotoxicity (specificity = 66%). A bedside scoring system accurately identified high-risk and low-risk patients. We believe these data add to the understanding of the clinical correlates of aminoglycoside nephrotoxicity and aid in the identification of high-risk patients.