The absence of nephrotoxicity and differential nephrotoxicity between tobramycin and gentamicin.
We conducted a prospective, double-blind, randomized trial of gentamicin and tobramycin to evaluate differences in nephrotoxicity. We evaluated levels of creatinine, creatinine clearance, beta 2-microglobulin, and N-acetyl-beta-D-glucosaminidase (NAG) as indicators of nephrotoxicity, and attempted to correlate them. Forty patients met the criteria for evaluation; 14 were given tobramycin and the remaining 26 received gentamicin. Significant nephrotoxicity, as defined by an increase in creatinine of 0.5 mg/dL, did not occur in either group. Increases in beta 2-microglobulin values were seen in 67% of the patients in the tobramycin group, and 52% of those in the gentamicin group. Elevations in NAG levels occurred in 54% of those in the tobramycin group and 52% of those in the gentamicin group. Elevation of NAG and beta 2-microglobulin levels was congruent in only 40% of the cases. We conclude that there was no significant difference in nephrotoxicity between gentamicin and tobramycin. Elevations of NAG and beta 2-microglobulin occurred at rates similar to those reported in the literature, but they did not correlate with significant nephrotoxicity.
Kepczyk
T
T
Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Tex 78234-6200.
Ryan
P J
PJ
McAllister
K
K
Otraje
J
J
D000118:Acetylglucosaminidase / Q000097:blood; D000328:Adult; D000368:Aged; D003401:Creatine / Q000097:blood / Q000652:urine; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005069:Evaluation Studies as Topic; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000139:chemically induced* / Q000652:urine; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012737:Sex Factors; D013997:Time Factors; D014031:Tobramycin / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D001613:beta 2-Microglobulin / Q000032:analysis
D005839:Gentamicins; D001613:beta 2-Microglobulin; D000118:Acetylglucosaminidase; D003401:Creatine; D014031:Tobramycin