Data relating to
amikacin resistance among gram-negative bacilli were obtained by means of a review of published literature and resistance surveillance studies. Data from the first several years of
amikacin use are difficult to interpret because the 10-micrograms disk used for Kirby-Bauer susceptibility testing resulted in apparent greater resistance than the present 30-micrograms disk. A large United States susceptibility surveillance program that monitors
antibiotic use has shown a trend since 1977 of greater susceptibility of Serratia species and greater resistance among Pseudomonas aeruginosa for all the
aminoglycosides. Pseudomonas resistance to
amikacin has shown the smallest increase of any
aminoglycoside. Several hospitals (Strong Memorial Hospital, University of Maryland
Cancer Center, and Minneapolis Veterans Administration Medical Center) have reported either no significant change or a decrease in resistance to
amikacin when it was the most frequently used
aminoglycoside. In a large, 14-center, prospective study, high-level use of
amikacin resulted in a significant decrease in resistance to
gentamicin and
tobramycin (p less than 0.01) and a marginal increase (p less than 0.05) in
amikacin resistance. Significantly increased
amikacin resistance has been reported from two institutions, neither of which used
amikacin as the predominant
aminoglycoside. Overall, the high-level use of
amikacin in large multi-center surveillance programs for as long as five years has not resulted in a significant increase in
amikacin resistance rates at any of the individual institutions surveyed.