Aminoglycoside clearance in patients with cystic fibrosis [letter].

We have been utilizing a patient's individual pharmacokinetic profile to plan and 
monitor aminoglycoside therapy, and we have often noted what appeared to 
be an extremely rapid elimination rate of gentamicin in our patients 
with cystic fibrosis. The patients with cystic fibrosis had significantly greater 
renal and total clearances than those without cystic fibrosis. If this 
observation could be extended to other drugs (such as the aminoglycosides), 
which are not normally subject to renal secretion, it would prove 
intriguing evidence for a possible primary renal defect in these patients. 
