[Assessment of the nephrotoxicity of amikacin in patients with cystic fibrosis].

Cystic fibrosis patients are at risk for nephrotoxic effects of aminoglycosides. Fifteen cystic fibrosis patients were admitted to hospital with 18 acute exacerbations of pulmonary symptoms associated with the isolation of Pseudomonas aeruginosa from sputum. They were treated intravenously with amikacin and ceftazidime for 14 days. Urinary excretion of N-acetyl-beta-D-glucosaminidase and alpha 1-microglobulin, two markers of tubular damage, and of albumin, a marker of glomerular permeability, was studied before and during treatment. Urinary activity of N-acetyl-beta-D-glucosaminidase and excretion of alpha 1-microglobulin was normal before amikacin treatment in approximately two thirds of patients and pathologically increased at the end of the study in 95%. Urinary albumin excretion was always normal before amikacin treatment and failed to increase consistently during treatment. The pattern of urinary protein excretion observed in the study before and during treatment with amikacin indicates a selective tubular toxicity.